3D Printing, Additive Manufacturing, SLA, SLS, FDM, Metal Powder Bed Fusion, DMLS, EBM & Aerospace AM HVAC Duct Guide

1. Why additive manufacturing HVAC is its own engineering discipline

Additive manufacturing is the most chemically and thermally polymorphic manufacturing technology in the modern Australian industrial economy. Within a single facility — CSIRO Lab22 at Clayton VIC, the Amaero International production hall at Notting Hill, AML3D’s WAAM bays in Adelaide, or the Materialise medical-AM cleanroom in Sydney — you can find pyrophoric titanium powder in one room, photopolymer urethane resin emitting isocyanate vapour in the next, FDM filament off-gassing styrene and acetone three doors down, and a 1200 °C HIP vessel venting argon in the back. Each process has its own characteristic dust load, fume chemistry, ignition risk, hazardous-area zoning requirement and material specification. HVAC ductwork inside an AM facility is not a commodity item. It is a process-engineering problem that touches NFPA 484 combustible-metal deflagration safety, AS/NZS 60079 hazardous-area electrical compliance, ASTM F2924 powder feedstock traceability, AS 9100 aerospace quality assurance, ISO 13485 medical-device manufacturing control, NADCAP special-process audit, TGA biomedical regulation, and ARPANSA ionising-radiation safety, all sitting inside the same building envelope.

This guide writes against the full breadth of the Australian AM sector as it exists in 2026. Metal powder bed fusion (SLM/DMLS/EBM) is the highest-value tier — Amaero International ASX:3DA at Notting Hill VIC operates the country’s largest aerospace metal AM fleet, supplying Ti-6Al-4V (ASTM F2924) and Ti-6Al-4V ELI (F3001) parts to Hypersonix Launch Systems, Department of Defence DSTG, and the broader Australian aerospace supply chain. Stryker Australia, Medtronic Australia and Cochlear all run dedicated SLM and EBM machines for orthopaedic, surgical and cochlear-implant components under TGA TGO 92 and ISO 13485. Materialise Australia, the Belgian-owned medical AM specialist, runs Sydney and Melbourne service centres covering dental, craniofacial and orthopaedic printing in CoCr (ASTM F3213), titanium (F3001) and PA12 nylon. Wire arc additive manufacturing (WAAM) is dominated by AML3D ASX:AL3 in Adelaide, which has scaled from R&D origins at the University of Wollongong into a publicly listed defence supplier producing submarine pressure-hull, propulsion and structural components for HMAS Stirling, Anduril Australia and broader Department of Defence contracts. AML3D also runs a second production hub at the Stem Cell Park site supporting copper, stainless, Inconel and titanium WAAM in industrial volumes.

Cold spray additive manufacturing is the Australian-grown specialty — Titomic ASX:TTT at Notting Hill VIC produces large-format cold-spray parts in titanium, copper and steel for Boeing, Lockheed Martin and defence customers, while SPEE3D in Darwin NT pioneers field-deployable cold spray for Hypersonix, the Australian National University and DSTG Defence research applications. Aurora Labs ASX:A3D at Mt Marshall WA develops large-format metal powder bed printers targeting industrial-scale single-machine throughput. Polymer AM is dominated by 3D Industries Australia (Sydney and Melbourne service bureau capacity across FDM, SLA, SLS and Multi Jet Fusion), with installed bases of EOS, Stratasys, HP Multi Jet Fusion, 3D Systems, Formlabs, Carbon, Markforged composite FDM, Ultimaker, Raise3D, Prusa, Bambu Lab and Creality machines. Bastion Cycles in Melbourne produces titanium 3D-printed bicycle frame lugs as a niche premium consumer-product AM exemplar. Luyten 3D operates Australia’s first concrete 3D printing service from Sydney, Melbourne and South Australia sites, producing structural and architectural concrete elements at the large-format gantry scale. CSIRO Lab22 at Clayton VIC is Australia’s national AM research facility, with parallel installations at ANU, Monash University, the University of Sydney, RMIT, the University of Wollongong, the University of Adelaide and Swinburne University.

Across this entire sector, AM ductwork must survive five simultaneous demands. Combustible-metal deflagration resistance (NFPA 484 Class D titanium, aluminium and magnesium fines; AS/NZS 60079 Zone 20/21/22 hazardous-area zoning; ATEX-rated conductive flange gaskets and continuous earth bonding). Chemical fume resistance (HF and HCl from pickling, IPA and acetone solvent VOC from polymer cleaning, isocyanate from urethane photopolymers). High-temperature service (170–185 °C SLS sinter chamber, 600–800 °C stress-relief, 1000–1200 °C HIP, 1500–2000 °C powder atomisation). Cleanroom and medical-AM cleanability (ISO 14644 Class 5/6/7/8, vapourised hydrogen peroxide VHP decontamination, formaldehyde and chlorine dioxide fumigation). And inert-gas asphyxiation control (argon, nitrogen and helium handling under AS 2865 confined-space rules with continuous O2 monitoring at the 19.5–23.5% breathing-air envelope). Each is manageable in isolation. Together they explain why a generic commercial fabricator treating an AM facility as just another industrial job loses money on the first project and walks away from the second.

This guide walks every major AM process zone and explains what changes about the ductwork. We start with the regulatory backbone, then map the AM facility section by section, then close with the SBKJ machine configuration that gives an Australian fabricator the production envelope to serve this market from Box Hill North VIC across the country.

2. The Australian regulatory stack — AS 1668.2, AS 4254, AS/NZS 60079, AS 3957, NFPA 484, NFPA 660, NFPA 86, ASTM F2924, ISO/ASTM 52900, AS 9100, ISO 13485, TGA TGO 92, NADCAP

Additive manufacturing HVAC in Australia sits at the intersection of more than two dozen overlapping standards and codes. Ignoring any one of them is a notice-of-non-compliance from SafeWork Australia, the state EPA, the Therapeutic Goods Administration, the Civil Aviation Safety Authority, or all four, waiting to happen. The standards stack splits into building-code compliance, occupational-health exposure compliance, hazardous-area electrical compliance, combustible-dust safety compliance, AM-specific material qualification, sector-specific quality management (aerospace and medical), and pressure-vessel and oven safety.

2.1 AS 1668.2 — mechanical ventilation for buildings

AS 1668.2 is the umbrella mechanical-ventilation standard for Australia. AM facilities fall under NCC Class 8 industrial occupancy; Table 4 of AS 1668.2 sets minimum extract rates for metal handling, machining, grinding, welding, painting and polymer-related operations. In practice an AM facility seldom gets close to the minimum — localised exhaust ventilation (LEV) at each individual dust and fume source drives total exhaust well above the building-volume figure. Where AS 1668.2 matters most is the make-up air requirement: every cubic metre extracted from a powder-bed chamber, SLS print room, FDM cabinet or HIP vent must be replaced by tempered, filtered, controlled-velocity supply air, keeping the production zones at neutral or slightly positive pressure relative to office and laboratory zones, and preventing inert-gas back-migration into occupied spaces.

2.2 AS 4254 — sheet metal duct construction

AS/NZS 4254.1 (sheet metal) and AS/NZS 4254.2 (flexible) govern duct construction across normal pressure ranges — low pressure (up to 500 Pa), medium pressure (up to 1000 Pa) and high pressure (up to 2500 Pa). Most AM facility supply air, general extract and polymer-related LEV sit inside AS 4254 ranges. HIP, heat-treatment oven exhaust and atomisation-tower exhaust in their refractory or high-temperature stainless sections run beyond AS 4254 and require purpose-engineered construction; AS 4254 picks up again on the cool side downstream of the cooling and dilution zone.

2.3 AS 1530.4 — fire-resistance of building elements

AS 1530.4 covers fire-resistance testing of building elements including fire-rated ductwork penetrations through fire compartments. In an AM facility this matters at every wall and floor penetration between production zones (Zone 20/21/22 dust hazard) and adjacent office, laboratory, server or evacuation zones — the duct penetration must be rated at 250 °C/2 hour fire integrity, with fire dampers complying with AS 1682 and the surrounding wall/floor assembly meeting the fire-resistance level (FRL) called by the building’s building code of Australia (BCA) approval.

2.4 AS/NZS 60079 — explosive atmospheres, the dominant electrical-safety standard

AS/NZS 60079 is the hazardous-area-classification standard. AM facilities trigger AS/NZS 60079.10.2 (dust) and AS/NZS 60079.10.1 (gas) at multiple locations:

• Zone 20: Continuous explosible-dust concentration. The interior of a powder-bed fusion chamber, the interior of a sieving station, the interior of a closed powder hopper, the interior of a powder transport line above settling velocity.
• Zone 21: Occasional explosible-dust release in normal operation. The depowdering station enclosure, the immediate area around an open sieve, the immediate area around a powder transfer hose.
• Zone 22: Unlikely release, short duration. The general powder-handling room around the equipment.
• Zone 1: Gas/vapour. SLA/DLP/Carbon DLS IPA wash stations, FDM acetone smoothing booths, photopolymer resin trays under operation.
• Zone 2: Gas/vapour, unlikely in normal operation. The general SLA room, the general FDM room.

AS/NZS 60079 drives Ex-rated electrical equipment requirements for fans, motors, instrumentation, duct-mounted sensors, lighting and any electrical device inside or near the affected zones. Ductwork itself must be conductive throughout (316L stainless is the default), continuously bonded with conductive ATEX-rated flange gaskets at every joint, externally bonded with copper or stainless bonding strap to the building earth grid, and pressure-tested with documented earth-resistance verification (less than 1 ohm to ground at every section) at commissioning.

2.5 AS 3957 — dust hazard areas, the critical AM standard

AS 3957 is the Australian dust-hazard standard and the most directly applicable single document for AM duct designers. It covers combustible dust deflagration risk — titanium fines (Kst 200–400, St2–St3), aluminium fines (Kst 200–400, St3), magnesium fines (Kst 300–700, St3), nickel and Inconel powder, stainless powder, CoCr powder, polymer SLS dust (PA12 nylon, PEEK, PA6, TPU), and combustible polymer FDM dust. AS 3957 mandates hazard-area zoning (Zone 20 for continuous explosible-dust concentration, Zone 21 for occasional, Zone 22 for unlikely), and drives the AS/NZS 60079.10.2 electrical-equipment selection downstream. For an AM duct designer, AS 3957 forces the question: at every dust collection point, what is the explosibility of the dust, what is the lowest minimum ignition energy, what is the deflagration index Kst, and what is the engineered deflagration-protection chain (vent panels per NFPA 68, inerting per NFPA 69, isolation valves, chemical suppression) between the wet-bath collector and the inbound duct? The answer drives wet-bath collector selection, isolation-valve placement and the bonding-and-grounding of every metre of duct in the dust-laden circuit.

2.6 AS 1940 — storage and handling of flammable and combustible liquids

AS 1940 governs the storage and handling of flammable liquids in Australian workplaces. AM facilities trigger AS 1940 at multiple stations: FDM filament storage (ABS, PLA, PETG, nylon, PEEK all qualify as combustible solids but their off-gas products trigger Zone 2; the acetone bath for ABS smoothing is a Class IB flammable liquid Zone 1). SLA/DLP/Carbon DLS uncured liquid photopolymer resin (most resins are Class IIIA combustible liquids, with the IPA wash station for post-print cleaning being a Class IB flammable liquid Zone 1). The chemical-etch and passivation stations (HF, HNO3, H2SO4, HCl) trigger AS 3780 and AS 4326. Each storage and handling point requires bunded containment, dedicated LEV branch, segregated storage cabinet and AS/NZS 60079 zoning around the immediate work area.

2.7 NFPA 484 — combustible metals, the dominant US-Australian engineering reference

NFPA 484 is the US National Fire Protection Association standard for combustible metals, referenced extensively by Australian AM insurance underwriters, ASX-listed AM operators and used as the de-facto engineering reference where AS standards are silent on specific powder-bed metallurgies. NFPA 484 covers titanium (Class D combustible, pyrophoric below 75 micron, water-reactive), aluminium and aluminium alloys (Class D, water-reactive due to H2 evolution), magnesium and magnesium alloys (Class D, the most reactive of the common AM metals), zinc, zirconium, hafnium, lithium, sodium, potassium, niobium, tantalum, thorium, uranium and combustible alloys of nickel, iron, copper and other metals where the powder cut is below 425 micron. For AM operators handling Ti-6Al-4V (ASTM F2924), Ti-6Al-4V ELI (F3001), AlSi10Mg (F3318), Inconel 718 (F3055), Inconel 625 (F3056), stainless 316L (F3184) or CoCr-28Mo (F3213) powder, NFPA 484 is the engineering bible.

NFPA 484 mandates wet-bath dust collection (with water or inert liquid) for fine aluminium, magnesium and titanium dust, prohibits dry baghouses without engineered deflagration venting per NFPA 68, and sets bonding, grounding and isolation-damper requirements that prevent a wet-bath fire or deflagration from propagating back into the ductwork main. Magnesium dust ignites at lower concentration than aluminium and is harder to extinguish (water reacts violently with hot magnesium), so a magnesium-bearing AM facility must use sealed wet-bath collectors with inert liquid or SF6/fluoroketone cover gas. Titanium fines below 30 micron can self-ignite at room temperature if disturbed; wet-bath collection plus argon inerting (NFPA 69) plus electrical bonding-to-earth at every duct section plus Class D dry-powder extinguisher infrastructure (never water, never CO2) is the standard topology.

2.8 NFPA 660 — consolidated dust standard (2025)

NFPA 660 is the 2025 consolidation standard merging the previous NFPA 61 (agricultural and food dust), 484 (combustible metals), 654 (combustible particulate solids) and 664 (woodworking dust) into a single document. For AM operators the dominant impact is on dust hazard analysis (DHA) documentation requirements — every facility handling combustible particulate solids must produce a written DHA mapping every point of dust generation, accumulation, ignition source and propagation path, with engineering controls documented for each. Australian AM facilities adopting NFPA 660 in 2026 face revised DHA documentation, updated bonding-and-grounding requirements, and tightened isolation-valve specifications between wet-bath collector and inbound duct.

2.9 NFPA 86 — industrial ovens and furnaces

NFPA 86 covers heat-treatment ovens, atomisation towers and post-process ovens running 170–2000 °C in AM facilities. Specifically: SLS sintering at 170–185 °C (PA12 nylon, TPU, PA6); SLA/DLP/Carbon DLS post-cure ovens at 40–80 °C (with UV at 365–405 nm and consequent ozone generation); stress-relief at 600–800 °C (Ti, Inconel, stainless); HIP at 1000–1200 °C and 100–200 MPa; anneal at 850–950 °C; gas atomisation at 1500–2000 °C. Exhaust topology under NFPA 86 includes LEL monitoring at every gas-fired burner (CH4 1.25% LEL methane, H2 4% LEL hydrogen on reducing-atmosphere furnaces), purge cycles before lighting, explosion venting on the oven shell, dedicated exhaust risers separate from general facility exhaust, and burner-management systems with redundant flame supervision.

2.10 ASTM F2924, F3001, F3055, F3056, F3318, F3184, F3213 — AM material specifications

ASTM F2924 (Ti-6Al-4V via powder bed fusion) is the most-referenced single material standard in Australian aerospace AM, covering Amaero International, AML3D, Titomic, Stryker, Medtronic, Bastion Cycles and most CSIRO Lab22 work. F3001 covers Ti-6Al-4V ELI (extra-low-interstitial) for medical implants and biomedical AM — the dominant medical-AM titanium specification at Stryker, Medtronic, Cochlear and Materialise. F3055 covers Inconel 718 nickel superalloy via PBF; F3056 covers Inconel 625. F3318 covers AlSi10Mg aluminium alloy via PBF (the standard production aluminium for aerospace AM). F3184 covers stainless 316L via PBF (the standard cleanroom-grade and medical stainless). F3213 covers CoCr-28Mo cobalt-chromium for medical implants (orthopaedic, dental and cardiovascular). Each standard sets chemistry, microstructure, mechanical-property and inspection requirements that flow back through the AM facility to ventilation cleanliness specifications (e.g. inert-atmosphere O2 cap at 0.1–0.5% for Ti-6Al-4V to prevent oxygen pickup).

2.11 ISO/ASTM 52900–52950 — AM process and quality standards

The ISO/ASTM 52900 series is the umbrella set of AM-specific quality and process standards developed jointly by ISO and ASTM. ISO/ASTM 52900 covers terminology. 52901 covers purchasing requirements between AM service provider and customer. 52902 covers test artefacts for benchmarking machines. 52904 covers process control specifications for laser PBF. 52907 covers metal powder feedstock characterisation (chemistry, particle size distribution, flowability, apparent density). 52911 covers laser PBF design rules. 52915 covers the additive manufacturing file format (AMF). 52920 covers qualification of part producers (the basis of AM facility audit). 52941 covers acceptance tests for laser PBF machines. Each standard ties back to facility infrastructure including HVAC: a 52920 qualified part producer must document its ventilation, dust collection and cleanroom infrastructure as part of the production qualification package.

2.12 AS 9100 aerospace and NADCAP — the aerospace AM audit

AS 9100 is the sector-specific aerospace quality management standard, layering aerospace-specific requirements over the general ISO 9001 base. Amaero International, AML3D, Titomic, SPEE3D and the aerospace customers of 3D Industries all operate AS 9100 certified. NADCAP (National Aerospace and Defense Contractors Accreditation Program) audits special processes including AM under AC7110/14, requiring documented control of every process variable from powder receiving through to final part — including the HVAC and dust collection infrastructure that touches the powder feedstock. The AS 9100/NADCAP audit trail flows back through the HVAC fabricator: every length of ductwork carrying powder feedstock must be traceable to its mill certificate, fabrication date, NATA-certified pressure test, earth-bonding verification and AS/NZS 60079 zone assignment.

2.13 ISO 13485 medical and TGA TGO 92 — the medical AM audit

ISO 13485 is the medical-device quality management standard. The Therapeutic Goods Administration (TGA) regulates medical-device manufacturing in Australia, with TGO 92 (Therapeutic Goods Order 92) the specific manufacturing-conditions standard. Stryker Australia 3D-printed orthopaedic implants, Medtronic 3D-printed surgical instruments and craniofacial implants, Cochlear 3D-printed implant components and Materialise Sydney/Melbourne dental, orthopaedic and craniofacial AM all operate under ISO 13485 + TGO 92 + FDA 21 CFR 820 (for US-market product). Cleanroom HVAC under ISO 14644 (Class 5/6/7/8 cleanrooms with HEPA-filtered supply at 0.3 m/s laminar flow) is a fundamental requirement; the ductwork serving the cleanroom must be 316L stainless throughout, hermetically welded, and qualified with documented integrity testing.

2.14 AS 4036, AS 4458, AS 3920, AS/NZS 1200 — pressure vessel and HIP regulation

Hot Isostatic Pressing (HIP) operates at 100–200 MPa argon or nitrogen pressure inside a registered pressure vessel. AS 4036 covers boilers and pressure vessels; AS 4458 covers fabrication of unfired pressure vessels; AS 3920 covers assurance of product quality for pressure equipment; AS/NZS 1200 covers pressure equipment generally. HIP exhaust ductwork falls under AS 4254 for the post-cooling general extract, but the connection between the HIP vessel vent line and the building exhaust must be designed for pressure-relief blowdown (sized for the maximum credible vent rate during emergency depressurisation) and inerting (argon or nitrogen displacement of the local atmosphere). Bodycote Australia and Outokumpu HIP run commercial HIP services in Australia; AML3D, Amaero and CSIRO Lab22 own or subcontract HIP capacity for in-house post-processing.

2.15 AS/NZS 1715, AS/NZS 1716, AS/NZS 2982 — respiratory protection and fume cupboards

AS/NZS 1715 sets the framework for respiratory protective equipment selection, use and maintenance. AS/NZS 1716 sets equipment standards. For metal powder handling at AM facilities, powered air-purifying respirators (PAPR) with HEPA + particulate cartridges plus full-body anti-static powder-handling suits are mandatory at depowdering, sieving and recycling. AS/NZS 2982 covers fume cupboards and laboratory ventilation — relevant in AM chemistry labs (powder characterisation, mechanical-property testing, microstructure analysis) and at chemical-etch and passivation stations.

2.16 CASA, FAA, EASA, NATA — aerospace and certification authorities

Civil Aviation Safety Authority (CASA) is the Australian aerospace regulator. The Federal Aviation Administration (FAA, US) and European Union Aviation Safety Agency (EASA) are the major Western certification authorities. Amaero International, AML3D, Titomic and SPEE3D all produce parts for FAA/EASA-certified aerospace assemblies, with the AM facility audit trail flowing through to flight-safety qualification. NATA (National Association of Testing Authorities) is the Australian laboratory accreditation body; NATA-certified labs perform the powder characterisation, mechanical testing and metallurgical analysis that underpin AS 9100 and NADCAP compliance.

2.17 SafeWork Australia workplace exposure standards — the chemistry-driven sizing inputs

SafeWork Australia’s workplace exposure standards (WES) are the regulatory inputs that drive LEV capture velocity and ductwork sizing across the AM facility. The AM-relevant standards are extensive:

• Titanium (inhalable): 5 mg/m³ TWA. Plus Ti fines NFPA 484 pyrophoric and water-reactive — THE KILLER Class D combustible metal across Amaero, AML3D, Titomic, SPEE3D, Aurora Labs, Stryker, Medtronic, Cochlear and aerospace/defence AM.
• Aluminium (metal): 1 mg/m³. Aluminium oxide 10 mg/m³. Al fines NFPA 484 with H2 evolution from water reactivity.
• Magnesium: 5 mg/m³. Mg fines NFPA 484 pyrophoric — the most reactive of common AM metals.
• Chromium VI (hexavalent): 0.05 mg/m³ STEL. From stainless 316L, Inconel 625/718, CoCr alloy and Ni-Co AM powder + WAAM fume; IARC Group 1 human carcinogen.
• Nickel (inhalable): 1 mg/m³. Insoluble Ni compounds 0.1 mg/m³. From Inconel, Hastelloy, stainless, Monel, nickel-cobalt alloys.
• Cobalt: 0.02 mg/m³ STEL. From CoCr medical-implant alloy, HIP processing. IARC Group 2B possible carcinogen.
• Beryllium: 0.001 mg/m³ STEL. From Cu-Be rare super-alloy AM work. One of the lowest WES in the Australian standard.
• Formaldehyde: 1 ppm STEL. From SLA photopolymer monomer, SLS PA12 thermal degradation, FDM ABS off-gas, resin solvent and IPA cleaning by-products.
• Isocyanate (TDI/MDI): 0.005 ppm STEL. From SLA photopolymer, urethane resin (Carbon DLS EPU/RPU, EnvisionTec urethane, Stratasys Origin urethane). Acute respiratory sensitiser, endocrine disruptor — THE KILLER of polymer AM. Being progressively phased out of new resin formulations.
• Epoxy resin: Skin sensitiser, contact dermatitis. DLP epoxy resins.
• Polymer dust general: 5 mg/m³ inhalable cap. ABS, PLA, nylon, PA12, TPU, PETG, PEEK FDM filament dust and SLS powder. Static-electrified and prone to accumulation.
• VOC general: Variable. From FDM thermal degradation, SLA UV cure, acrylate monomer, ABS off-gas, acetone, IPA, MEK, MIBK, ethyl acetate, toluene, xylene.
• MEK methyl ethyl ketone: 200 ppm. Plus IPA isopropanol 400, acetone 250, ethyl acetate 200, toluene 50, xylene 50, MIBK methyl isobutyl ketone 50. Filament cleaning, SLA resin cleaning, FDM acetone vapour smoothing.
• Ozone (O3): 0.1 ppm STEL. From UV cure SLA, DLP, Carbon DLS, laser ionisation, electron beam EBM.
• Carbon monoxide (CO): 30 ppm STEL. From HIP, stress-relief, anneal, LPG burner, acetylene weld, atomiser combustion.
• Carbon dioxide (CO2): 5000 ppm. Indoor air quality marker; rises in poorly ventilated AM cells.
• Argon (Ar): Asphyxiation hazard. SLM atmosphere, EBM atmosphere, HIP, heat-treat. Cap O2 19.5–23.5% breathing air; AS 2865 confined-space entry permit required for any vessel entry.
• Nitrogen (N2): Asphyxiation hazard. SLM (alternative to Ar), EBM atmosphere, HIP, heat-treat, post-process. Same O2 cap and confined-space rules.
• Helium (He): Asphyxiation hazard. Heat-treat, atomiser, cold spray propellant.
• Hydrogen (H2): 4% LEL lower explosive limit. Reducing-atmosphere heat-treat, post-process.
• Methane (CH4): 1.25% LEL. LPG and natural gas furnace, acetylene, atomiser.
• Hydrogen fluoride (HF): 1.8 ppm STEL. Titanium pre-paint etch, aluminium pre-paint, chemistry, pickling.
• HCl, HNO3, H2SO4: 5 / 4 / 1 ppm STEL respectively. Post-process descaling, pickling, stainless passivation, photo-resist.
• Hydrogen cyanide (HCN): 5 ppm STEL. Rare emergency — fire involving nylon SLS combustion releases HCN.
• Respirable crystalline silica (RCS): 0.05 mg/m³. From sand-blast post-process, alumina media blast and concrete 3D printing.

Every dust and fume LEV branch in an AM facility has to keep the operator’s breathing-zone air below the relevant WES. Where multiple contaminants are present (Cr VI plus Ni plus Co at a CoCr powder-handling station), the additive-mixture rule applies and the LEV must be sized to the lowest practical fraction. This is the calculation that drives capture velocity, transport velocity, branch sizing and main sizing across every AM duct system.

3. Process zones — the AM facility end-to-end

The most reliable way to specify AM HVAC is to walk the process flow. Every Australian AM facility maps to a variant of the same end-to-end sequence: design and CAD, powder atomisation or feedstock receiving, powder storage and handling, the AM process itself (one or more of SLM/DMLS/EBM, WAAM, cold spray, SLS, SLA/DLP/DLS, FDM, concrete), post-process (depowdering, support removal, washing, curing), HIP and heat treatment, CNC machining, chemical etch and passivation, surface finish, non-destructive testing and QC, dental/medical/aerospace production-cell finishing, and packaging. Each station has its own characteristic dust load, fume chemistry, temperature, capture velocity and material requirement.

3.1 Design, CAD, CAM, topology optimisation and simulation — the cleanest zone

The AM design office is the cleanest part of any AM facility. Australian AM designers run Autodesk Fusion 360, SolidWorks, NX, CATIA, Ansys, Abaqus, COMSOL, Materialise Magics and Netfabb for topology optimisation, generative design, lattice generation and process simulation. The LEV demand here is essentially nil; the HVAC demand is environmental conditioning to ASHRAE TC 9.9 Class A1 (18–27 °C, 20–80% RH) plus ESD control (anti-static flooring, controlled humidity 40–55%). Supply-air ductwork is conventional galvanised spiral to AS/NZS 4254 medium pressure, with HEPA pre-filters at the diffuser and slight positive pressure relative to the production-floor zones. The design office is the natural location for the SCADA control room overseeing AM build queues, HIP cycles, powder inventory and quality data.

3.2 Powder atomisation and feedstock production — gas atomisation, plasma rotating electrode

Powder atomisation is the production process that creates the metal feedstock for SLM, DMLS, EBM and cold spray. Three dominant technologies: gas atomisation (molten metal stream broken into droplets by high-pressure inert-gas jet), plasma rotating electrode (PREP, metal electrode spun at high RPM with plasma torch ablating droplets from the rim) and water atomisation (metal stream broken by water jet, used for less reactive metals and for lower-spec powders). Amaero International operates in-house gas atomisation capacity for proprietary Ti and Inconel feedstocks at its Notting Hill VIC plant; Aurora Labs at Mt Marshall WA has developed in-house atomisation as part of its large-format printer ecosystem; Sandvik Additive runs atomisation at international scale supplying the Australian market; CSIRO Lab22 operates pilot-scale atomisation for R&D work.

Atomisation is a high-temperature, high-hazard process. The metal stream is held at 1500–2000 °C; the atomising chamber is filled with argon or nitrogen at 0.5–2.0 MPa; the resulting powder is collected in cyclone separators and classified by particle size (15–150 micron typical for PBF feedstock, 5–25 micron for cold spray, 45–150 micron for EBM). The HVAC envelope splits into three sub-systems: atomisation chamber exhaust (309/310S high-temperature stainless main, refractory-lined first 5 m, dedicated wet-bath collector for the fine fraction below 5 micron), classifier and sieving station LEV (Zone 20/21/22 dust hazard, 316L stainless mains, ATEX bonding throughout, wet-bath collection), and packaging-station LEV (Zone 22, 316L stainless, HEPA polish). The classifier and packaging are typically housed in a glove-box style enclosure with inert-gas blanket and continuous O2 monitoring at the operator interface (cap 19.5–23.5% breathing air). Atomisation is the highest single-hazard zone in an AM facility — molten metal at 2000 °C plus high-pressure inert gas plus fine pyrophoric powder is the worst-case combination, and the HVAC must engineer separation and explosion-isolation to a higher tier than anywhere else in the building.

3.3 Powder storage, handling and recycling — the dominant Zone 20/21/22 envelope

Powder storage and handling consumes more cubic metres of ductwork than any other zone in a typical metal AM facility. Powder arrives in sealed drums or super-sacks (Sandvik, EOS, Carpenter, Praxair, Hoganas-supplied, or Amaero/Aurora Labs in-house) and is transferred to bulk storage hoppers via inert-gas-blanketed transfer hoses. From bulk storage, powder is dosed into the AM machine’s dose feed hopper, the build chamber consumes a fraction of the dose, and the unconsumed powder is recycled through sieving stations (typically 75 micron cut for Ti, 53 micron for Al, 90 micron for Inconel) back to the dose feed. The total powder inventory in active circulation at a typical Amaero International production cell is 200–500 kg per machine.

The HVAC envelope at every powder handling point is identical in principle: enclose the powder transfer in a sealed hopper, glove-box or sieving cabinet with inert-gas blanket (argon or nitrogen at 0.5–1.0% O2 cap), LEV at the operator interface at 0.5–1.0 m/s capture velocity into a 316L stainless 200–400 mm diameter branch at 18–22 m/s transport, terminating at a wet-bath dust collector with isolation valve (NFPA 68/69 compliant) and stack discharge after second-stage HEPA polish. The duct between the sieving cabinet and the wet-bath collector is the highest-risk single segment in the facility; it must be 316L stainless, continuously TIG-welded longitudinally (SBSF-1525), conductively bonded at every flange (resistance below 1 ohm to ground), and routed with the minimum possible bends to prevent powder accumulation at elbows. ATEX-rated conductive flange gaskets are mandatory at every joint.

3.4 Selective Laser Melting (SLM) and Direct Metal Laser Sintering (DMLS)

SLM and DMLS are functionally the same process — a 200–500 W fibre laser scans a powder bed inside an argon or nitrogen-inerted chamber, melting and fusing thin layers (20–100 micron) of metal powder onto previously-built layers. SLM is the SLM Solutions trademark (now Nikon SLM after Nikon’s 2023 acquisition); DMLS is the EOS trademark. Machines in this category include EOS M290/M300/M400, SLM Solutions NXG XII 600, TRUMPF TruPrint 3000/5000, Renishaw RenAM 500Q/S, Concept Laser M2/M4 (now GE Additive), Velo3D Sapphire and the various Australian-developed alternatives at Amaero International and Aurora Labs.

The HVAC envelope around an SLM/DMLS cell has four major sub-systems. First, the argon make-up plant — bulk LAr storage tank (typically 30,000 L cryogenic vessel outdoors) with vapouriser, regulator, distribution piping in 316L stainless to the machine plenum, and O2 monitoring at the machine interface. Second, the chamber vent — during build, the chamber is closed and inert; between builds, the chamber must be vented to atmosphere (with the residual argon displacement causing localised oxygen depletion); the vent line is 316L stainless to a Zone 22 controlled discharge with O2 monitoring at the vent exit point. Third, the chamber filter circuit — the laser plume products (fine condensate from the melt pool, fume from the burning organic binder traces, fine ejected powder) are scrubbed by chamber-mounted recirculation filter (typically HEPA + activated carbon) with the filter element disposed of as Class D combustible-metal waste. Fourth, the depowdering and removal station — after build complete, the operator opens the chamber, extracts the build platform, and depowders the part inside a sealed Zone 20 cabinet with LEV captured into a 316L stainless 200 mm main at 18–22 m/s transport.

For Amaero International (the country’s biggest SLM/DMLS operator), Stryker, Medtronic, Materialise and CSIRO Lab22, the dominant HVAC engineering decision is the routing of the depowdering LEV. Every machine has its own depowdering station; each station feeds a branch into the facility wet-bath dust collection main; the collector serves multiple machines from a single trunk; the trunk must be sized for the maximum credible coincident depowdering load (typically 50% of installed machines depowdering simultaneously). The wet-bath collector itself is sized at 5000–15000 m³/h for a 4-to-8-machine facility.

3.5 Electron Beam Melting (EBM) and high-vacuum metal AM

Electron Beam Melting (EBM) is the second metal powder bed technology, dominated commercially by GE Additive Arcam machines. EBM runs a high-power electron-beam gun under high vacuum (10⁻³ to 10⁻⁵ mbar) instead of inert gas, eliminating argon asphyxiation risk at the build chamber but adding ionising radiation control (X-ray bremsstrahlung from the electron beam striking the powder bed). The chamber is a vacuum vessel; the HVAC role here is post-cycle backfill (typically inert gas to atmospheric pressure before opening) and operator-zone radiation interlocking.

EBM is used at CSIRO Lab22, the University of Adelaide and Stryker for medical-implant titanium production. The HVAC envelope is simpler than SLM in some respects (no argon distribution to the build chamber) but adds the ionising-radiation envelope — ARPANSA RPS 1 radiation safety, lead-shielded enclosure, X-ray leak monitoring at operator location, and interlocked door access. The depowdering and post-process LEV is functionally identical to SLM/DMLS.

3.6 Wire Arc Additive Manufacturing (WAAM) — AML3D Adelaide submarine and defence

WAAM is the dominant AM process at AML3D ASX:AL3 in Adelaide, the country’s largest WAAM operator. WAAM uses a robotic MIG or TIG arc to deposit metal wire feedstock layer by layer, producing large-format structural components in stainless 316L, Inconel 625/718, titanium, copper, mild steel and tool steel. AML3D supplies submarine pressure-hull, propulsion and structural components for HMAS Stirling, Anduril Australia structural and aerospace components, and broader Department of Defence work. The Stem Cell Park production hub adds copper conductor and bus-bar WAAM capacity.

The HVAC envelope around a WAAM cell resembles a heavy welding workshop more than a powder-bed AM facility. There is no powder, no inert chamber, no laser — instead, an arc operating at 1500–3000 amps deposits 5–15 kg of metal per hour, generating significant welding fume: Mn manganese (0.2 mg/m³ WES) and Fe2O3 iron oxide (5 mg/m³) on mild steel, Cr VI hexavalent chromium (0.05 mg/m³ STEL) on stainless and Inconel feedstock, Ni inhalable (1 mg/m³) and insoluble (0.1 mg/m³) on Inconel, Hastelloy and stainless, plus Cu, Mo and the various trace alloy elements. UV from the arc plasma plus ozone generation from the air ionised by the UV adds an additional respiratory exposure.

AS/NZS 4453 mandates welding-fume capture and control. WAAM at AML3D uses overhead canopy capture (1.5–2.5 m/s capture velocity at the arc), high-volume low-velocity (HVLV) extraction over the build bed, plus localised on-tool extraction at the welding torch. The dust main is 316L stainless at 18–22 m/s transport velocity to a dedicated baghouse with HEPA polish for stainless and Inconel Cr VI streams. Cr VI continuous emissions monitoring is fitted at the stack to verify discharge below the EPA stack-emissions licence limit. Each WAAM bay has its own dedicated extraction circuit; the trunk main consolidating multiple bays is sized for 100% coincident load (since WAAM is continuous-duty during builds).

3.7 Cold Spray Additive Manufacturing — Titomic and SPEE3D

Cold spray AM is the Australian-grown specialty — Titomic ASX:TTT at Notting Hill VIC and SPEE3D in Darwin NT both pioneered and commercialised cold spray AM technology with significant exports to Boeing, Lockheed Martin, Hypersonix, the Australian National University and DSTG Defence. Cold spray accelerates metal powder (typically 5–25 micron Ti, Al, Cu, stainless, Ni) to supersonic velocity (600–1200 m/s) using a high-pressure inert-gas (N2 or He) propellant jet through a converging-diverging nozzle. The powder strikes the substrate at velocity, plastically deforming and bonding without melting. Particle temperature stays well below the melting point of the metal.

The HVAC envelope around a cold spray cell is dominated by three demands. First, propellant gas exhaust — the high-pressure nitrogen or helium jet exhausts into the booth at high volume (typically 2000–8000 m³/h N2 or He depending on nozzle size), and the booth must be continuously vented to atmosphere with O2 monitoring at the booth exterior (cap 19.5–23.5% breathing air at any human-occupied zone). AS 2865 confined-space entry permit is required for any operator entry into the booth. Second, rebound powder capture — cold spray deposition efficiency is 60–90% depending on geometry; the remainder rebounds off the part or off the booth interior. This rebound is fine metal powder, NFPA 484 Class D combustible, and must be captured by 316L stainless LEV at 18–22 m/s transport into a wet-bath dust collector. Third, booth interior cleanup — periodic cleaning of accumulated rebound powder from the booth interior is itself a Zone 20/21 task with full PAPR and anti-static suit, with the vacuum exhaust into the same wet-bath circuit.

SPEE3D in Darwin NT operates the world’s first field-deployable cold spray system — the WarpSPEE3D portable unit, designed for in-field repair of military vehicles at remote bases. The HVAC implications for in-field cold spray are different from the factory installation; the operator must wear PAPR and the surrounding area must be controlled for inert-gas accumulation, but no fixed ductwork is involved.

3.8 Polymer Selective Laser Sintering (SLS) — PA12, PEEK, TPU, PP

Polymer SLS is the dominant high-throughput plastic AM process for production parts. The print bed holds a layer of polymer powder (PA12 nylon is the standard, with PA11, TPU thermoplastic polyurethane, PA6, PEEK polyetheretherketone and PP polypropylene also available); a CO2 or fibre laser scans and sinters a cross-section; the build platform descends, a fresh powder layer is deposited, and the cycle repeats. Machine vendors include EOS (the SLS pioneer), Stratasys, HP Multi Jet Fusion (a closely related process using inkjet absorbing-agent rather than direct laser), Sintratec, Formlabs Fuse and the various low-end alternatives. 3D Industries Australia operates one of the country’s biggest commercial SLS service-bureau fleets across Sydney and Melbourne.

The HVAC envelope around an SLS cell has three demands. First, the print chamber is heated to 170–185 °C for PA12 sintering, with the chamber atmosphere typically inerted with nitrogen to control oxidation. Chamber vent is 316L stainless to a Zone 2 controlled vent with VOC and polymer dust capture. Second, the powder-handling station around the machine (loading, unloading, sieving, recycling) is a Zone 21/22 polymer dust envelope — PA12 powder is combustible at fine cut (5–100 micron typical) with Kst 30–150 (St1 to St2). LEV captures the powder dust at 0.5–1.0 m/s into a 316L stainless 150–300 mm branch at 18–22 m/s transport into a dedicated polymer-dust baghouse with HEPA polish and explosion isolation (NFPA 68 vent panels and NFPA 69 inerting where Kst exceeds 100). Third, the post-process bead-blast or media-blast station for surface finish is an additional dust LEV branch with its own baghouse circuit.

3.9 Photopolymer Stereolithography (SLA), Digital Light Processing (DLP) and Carbon Digital Light Synthesis (DLS)

Photopolymer AM is the precision-feature plastic process tier. SLA stereolithography uses a UV laser (typically 355 or 405 nm) to scan and cure a thin layer of liquid photopolymer resin (3D Systems iPro, Stratasys Origin/Neo, Formlabs Form 4). DLP digital light processing uses a UV digital projector to cure an entire layer at once (EnvisionTec, Phrozen, Anycubic Photon, Elegoo Mars). Carbon DLS Digital Light Synthesis is the Carbon Inc. continuous-printing variant using a UV projector through an oxygen-permeable window to maintain a liquid interface (Carbon M2/M3/L1 machines). All three families share the same fundamental chemistry — liquid acrylate, methacrylate, urethane or epoxy resin cured by UV photopolymerisation.

The HVAC envelope around an SLA/DLP/DLS cell has three demands. First, the print cabinet itself is a Zone 2 VOC envelope — resin trays release acrylate vapour (formaldehyde 1 ppm STEL), and high-performance urethane resins (Carbon EPU/RPU, EnvisionTec urethane) release TDI/MDI isocyanate at 0.005 ppm STEL. Print cabinet exhaust is 316L stainless via 100–200 mm branch at 5–10 m/s capture into a VOC capture circuit (activated carbon adsorption or regenerative thermal oxidiser RTO depending on volume). Second, the wash station — uncured resin must be removed from the part with isopropanol (IPA) wash before post-cure; the IPA bath is a Zone 1 flammable-liquid envelope (IPA flash point 12 °C, Class IB) requiring explosion-rated equipment, dedicated LEV at the wash station, and AS 1940 storage of bulk IPA away from ignition sources. Third, the post-cure oven — UV post-cure at 365–405 nm generates ozone (O3 0.1 ppm STEL); the oven exhaust is 316L stainless to a separate ozone scrubber (KI catalyst or activated carbon).

Materialise Australia operates a substantial SLA fleet at Sydney and Melbourne for medical and dental work; the Materialise photopolymer LEV envelope is one of the most engineered in the Australian polymer AM sector, with full TGA TGO 92 documentation and ISO 13485 medical-device quality system underpinning every duct branch. Stryker, Medtronic, Cochlear and the dental-implant AM operators (Materialise Dental, Osteon Medical) all run dedicated SLA cells with TGA-audited LEV infrastructure.

3.10 Fused Deposition Modeling (FDM/FFF) — filament extrusion AM

FDM (Stratasys trademark) and FFF (open-source equivalent) are the most widely-installed plastic AM processes globally and across Australia. A heated extruder deposits melted thermoplastic filament (ABS, PLA, PETG, TPU, nylon, PA12, PEEK, polycarbonate, ABS-CF, PETG-CF) layer by layer to build the part. Machine vendors span the spectrum from premium industrial (Stratasys Fortus and F-series, Markforged composite Mark Two/X7/FX20, HP, Raise3D Pro2/3, Ultimaker S5/S7) through prosumer (Prusa MK4, Bambu Lab X1/P1) to entry-level (Creality Ender, Anycubic Vyper). 3D Industries Australia, RMIT, Monash, Swinburne and most Australian engineering firms operate FDM machines.

The HVAC envelope around an FDM cell is the lightest of the AM processes but is not nil. The dominant hazards are filament off-gas (ABS releases styrene, acrylonitrile and 1,3-butadiene at typical print temperatures 220–240 °C; PLA releases lactide and lower-toxicity VOC at 195–210 °C; PEEK and PEKK require 360–400 °C extrusion and release minor fluorinated compound off-gas; ABS-CF and PETG-CF release carbon-fibre dust during print) and polymer dust. The standard control is full enclosure of the print cabinet (Stratasys industrial machines are enclosed; Markforged are enclosed; the prosumer and entry-level machines are typically open) with HEPA + activated carbon recirculation filter, vented to the building general exhaust through a 316L stainless or aluminised steel branch. For ABS print cells specifically, the acetone vapour smoothing booth is a separate Zone 1 AS 1940 flammable-liquid envelope with dedicated explosion-rated LEV.

3.11 Construction 3D printing — concrete and large-format extrusion (Luyten 3D)

Luyten 3D is Australia’s first commercial concrete 3D printing operator, with Sydney, Melbourne and South Australia production sites and an exported gantry-printer product line. Concrete 3D printing uses a large-format gantry or robotic-arm system to deposit Portland-cement, aggregate and admixture mix layer-by-layer to build structural and architectural concrete elements (walls, columns, formwork, urban-furniture, prototype housing).

The HVAC envelope around a concrete 3D printing cell is dominated by respirable crystalline silica (RCS) control. Portland cement, fly ash supplementary cementitious materials, silica fume, aggregate and the various admixtures all contain crystalline silica. SafeWork Australia’s RCS WES of 0.05 mg/m³ drives LEV at every dry-material handling station — cement silo discharge, dry-mix mixing, hopper transfer, gantry-print build envelope (where the concrete leaves the nozzle, some fine cement and aggregate becomes airborne). 316L stainless or hot-dip aluminised steel mains at 18–22 m/s transport into a baghouse with cyclone pre-separator; the wet-side of the operation (mixing water introduction onwards) is conventional construction with no significant LEV demand. CSIRO has run concrete 3D printing research at Geelong VIC; the Luyten 3D production hubs are the country’s most active commercial sites.

3.12 Hot Isostatic Pressing (HIP) and post-process heat treatment

HIP is the densification step that fuses residual porosity in AM metal parts. The part is loaded into a registered pressure vessel; the vessel is pressurised with argon (sometimes nitrogen) to 100–200 MPa and heated to 1000–1200 °C; the combination of pressure and heat closes voids and produces a fully-dense microstructure. HIP cycle time is typically 4–8 hours including ramp and cool. Bodycote Australia and Outokumpu HIP run commercial HIP services in Australia; AML3D, Amaero and CSIRO Lab22 either own HIP capacity or subcontract to these providers.

Stress-relief, anneal and solution-treat ovens run at 600–950 °C (Ti) or 850–1100 °C (Inconel) for residual-stress reduction and microstructure homogenisation. These are conventional industrial ovens with refractory-lined steel construction, gas-fired (LPG or natural gas) or electric resistance, with NFPA 86 exhaust topology.

The HVAC envelope splits into three sub-systems. First, the HIP loading airlock LEV — when the vessel door opens after the cool-down, residual argon (heavier than air) sinks out and must be captured at floor level into a 316L stainless 300–500 mm branch at 5–10 m/s capture, discharging to atmosphere via the building general exhaust. O2 monitoring at the operator’s breathing zone (cap 19.5–23.5%) is mandatory. Second, the HIP cycle vent — at end of cycle, the vessel must be depressurised from 200 MPa to atmospheric, releasing a large volume of argon over a short period; the vent line is 309/310S high-temperature stainless or Inconel 625 (gas exits at 600–900 °C even after the cool ramp) through a dedicated discharge stack with operator-zone interlocks preventing approach during venting. Third, the heat-treat oven exhaust — LPG-fired ovens generate CO (30 ppm STEL), NOx and trace heavy metals; gas-fired oven exhaust is refractory-lined steel for the first 3–5 m, then 309/310S stainless cooling, then 316L through a baghouse + scrubber + stack discharge. Electric-resistance ovens have a simpler envelope with no combustion products.

3.13 Post-process CNC machining, polishing and surface finish

Most AM metal parts require post-process CNC machining to achieve tight dimensional tolerance, surface finish or feature accuracy that AM cannot produce directly — mating surfaces of mechanical assemblies, threaded features, bearing seats, sealing surfaces, datum surfaces for assembly. Machining is done on 5-axis CNC mills, lathes, EDM (electric-discharge machining), grinding and polishing wheels. Amaero International, AML3D, Aurora Labs, Stryker, Medtronic, Bastion Cycles and most metal-AM operators run post-process CNC in-house or subcontract to local machining houses.

The HVAC envelope around CNC machining of AM parts is dominated by metal dust capture (Cr VI on stainless, Ni and Co on Inconel and CoCr, Ti dust on titanium, Cu dust on copper alloys), cutting-fluid mist capture (water-soluble coolant mist or straight oil mist at face velocity 0.3–0.5 m/s) and the RCS load from any media-blast or sand-blast cleaning that follows. 316L stainless LEV mains at 18–22 m/s transport into a coalescer filter or electrostatic precipitator for mist, into a dust baghouse with HEPA polish for Cr VI and Co streams.

3.14 Chemical etch, pickling, descaling and stainless passivation

Some AM parts require chemical etch (titanium HF acid etch for surface conditioning, aluminium chemical etch for surface texture, stainless nitric-acid passivation) for downstream paint, coating or implant-surface treatment. The chemistry tree includes HF hydrogen fluoride (1.8 ppm STEL), HCl hydrochloric acid (5 ppm STEL), HNO3 nitric acid (4 ppm STEL), H2SO4 sulphuric acid (1 ppm STEL) and NaOH sodium hydroxide. Each station requires a dedicated 316L stainless or FRP fibreglass-reinforced-plastic LEV branch (HF attacks even 316L slowly; FRP is the preferred material for HF-bearing exhaust); capture velocity at the bath surface 0.5–1.0 m/s; transport 10–15 m/s (acid mist not abrasive but very corrosive); termination at a wet caustic scrubber (NaOH neutralisation) before stack discharge. AS/NZS 60079 hazardous-area zoning around the bath (Zone 1 above the bath surface, Zone 2 immediate surrounds) drives Ex-rated electrical equipment.

3.15 Non-destructive testing (NDT) — CT scan, X-ray, ultrasonic, dye penetrant, magnetic particle

Aerospace and medical AM parts require 100% NDT before release. The NDT suite typically includes industrial X-ray CT scanning (the dominant AM NDT technology for detecting internal porosity, inclusions, lack-of-fusion defects), conventional X-ray radiography, ultrasonic testing (UT), dye penetrant inspection (DPI) and magnetic particle inspection (MPI). The CT scanner sits in a lead-shielded enclosure with dedicated HVAC (ASHRAE TC 9.9 Class A1, 20±1 °C, 30–50% RH for X-ray tube stability) and a dedicated chilled-water cooling circuit for the X-ray tube. ARPANSA RPS 1 ionising radiation safety governs the room design.

Dye penetrant inspection uses solvent carrier (typically MEK methyl ethyl ketone at 200 ppm WES or kerosene-based developer) and a fluorescent or visible dye; LEV at the spray-and-wipe station is 316L stainless via 100–200 mm branch to a VOC carbon-adsorber. Magnetic particle inspection generates fine iron-oxide powder fume; LEV at the wet or dry MPI bench is 316L stainless to a dedicated baghouse. The NDT lab’s overall HVAC is conditioned for instrument stability and personnel comfort; it is the cleanest production-floor zone in the AM facility.

3.16 Medical AM production cells — Stryker, Medtronic, Cochlear, Materialise

Medical AM is the highest-precision, highest-cleanliness tier of the Australian AM sector. Stryker Australia 3D-prints orthopaedic implants (hip cups, knee components, cranial plates) in CoCr-28Mo (ASTM F3213), Ti-6Al-4V ELI (F3001) and stainless 316L (F3184). Medtronic Australia 3D-prints surgical instruments and patient-specific craniofacial implants in titanium and PEEK. Cochlear (Macquarie University NSW) 3D-prints implant components and surgical guides. Materialise Australia operates Belgian-owned Sydney and Melbourne service centres covering dental implants (titanium and CoCr), craniofacial implants (titanium and PEEK), orthopaedic prototypes (PA12 and titanium) and patient-specific surgical guides (PA12 and resin).

The HVAC envelope around a medical AM cell is the most demanding in the country. ISO 14644 Class 7 or Class 8 cleanroom (300,000 or 30,000 particles per cubic foot at 0.5 micron) is standard; some implant-cleaning and packaging operations require Class 5 (100 particles per cubic foot). Supply-air mains are 316L stainless throughout with HEPA polish at every diffuser; recirculation through HEPA + ULPA at the ceiling provides downflow at 0.3 m/s laminar. The exhaust side captures particulate at every operation with 316L stainless LEV. The cleanroom is positively pressurised relative to adjacent corridors at +10 to +25 Pa; airlocks between the cleanroom and the unclassified corridor have interlocked doors.

Cleanability is the other dominant demand. Cleanroom ductwork must withstand repeated decontamination cycles — vapourised hydrogen peroxide VHP at 30–800 ppm, formaldehyde fumigation at 0.5–1.0% w/w, chlorine dioxide at 0.5–1.0 mg/L. 316L stainless with continuous TIG welding (SBSF-1525) is the only practical material; lock seams sealed with silicone fail within months of VHP exposure. TGA TGO 92 documentation requires every length of cleanroom duct traceable to its mill certificate, fabrication date, pressure-test record and bonding/earthing verification.

3.17 Aerospace AM production cells — Amaero, AML3D, Titomic, SPEE3D, Quickstep, Bastion

Aerospace AM is the high-value, high-regulation tier of the Australian AM sector. Amaero International ASX:3DA produces aerospace structural and engine components for Hypersonix Launch Systems, the broader Australian aerospace supply chain and Department of Defence DSTG research. AML3D ASX:AL3 produces submarine pressure-hull and structural components for HMAS Stirling and defence customers including Anduril Australia. Titomic ASX:TTT cold-spray AM serves Boeing, Lockheed Martin and broader Western defence customers with large-format titanium and copper parts. SPEE3D operates field-deployable cold-spray AM for Hypersonix, the Australian National University, Department of Defence DSTG and field-deployment defence-vehicle repair scenarios. Quickstep ASX:QHL combines carbon-composite and metal-AM components for aerospace and defence assemblies. Bastion Cycles in Melbourne produces titanium 3D-printed bicycle frame lugs as a niche premium consumer-product AM exemplar — the production process is identical to aerospace titanium AM but at smaller scale.

The HVAC envelope around an aerospace AM cell sits above the medical AM envelope on regulatory documentation (AS 9100 + NADCAP + FAA + EASA + CASA stack) but slightly below on cleanroom classification (aerospace AM cells typically operate at ISO 14644 Class 8 rather than Class 7 or 5). The dominant infrastructure demands are NFPA 484 combustible-metal dust collection for titanium powder, AS/NZS 60079 Zone 20/21/22 hazardous-area zoning, dedicated argon make-up infrastructure (typically 30,000–60,000 L LAr storage outdoors with 316L distribution piping), and pre/post HIP staging space for batch handling.

4. Material selection — why galvanised fails and what replaces it

Galvanised duct is the workhorse of HVAC fabrication. Across data centres, commercial towers, hospitals and schools, hot-dip-galvanised carbon steel sheet to AS/NZS 4254 is the right answer for 95% of duct work. In an AM facility, it is the wrong answer for almost every duct. Five reasons drive material selection:

4.1 Galvanised carbon steel — the failure modes in AM

Galvanised carbon steel fails in AM exhaust for four reasons. First, temperature: zinc volatilises above 419 °C and fumes above 250 °C service. HIP and stress-relief oven exhaust at 600–1200 °C, atomisation tower exhaust at 1500–2000 °C and SLS chamber vent at 170–185 °C all approach or exceed safe service temperature of galvanising. Second, cleanability: galvanising develops white-rust (zinc hydroxide) under repeated VHP, formaldehyde or chlorine-dioxide cleaning cycles, contaminating medical and aerospace AM parts downstream. Third, chemical attack: HF from titanium etch, HCl from stainless passivation, acrylate monomer from SLA resin and acetone from FDM smoothing all attack zinc directly. Fourth, conductivity and bonding: NFPA 484 and AS/NZS 60079 Zone 20/21/22 ductwork must be continuously conductive with low resistance to ground; galvanising surface oxide raises contact resistance at flange joints and compromises the earth-bonding integrity that prevents static-discharge ignition of combustible powder.

4.2 316L stainless — the AM workhorse

316L stainless is the dominant material across every AM facility duct application. Composition Cr 16–18%, Ni 10–14%, Mo 2–3%, C ≤0.03% gives the corrosion resistance, weldability, cleanability and conductivity that match the AM demand. 316L withstands HIP exhaust (up to 600 °C continuous), CoCr and Inconel powder abrasion, HF acid etch (slow attack), VHP cleanroom decontamination (no measurable attack over 10-year service), and gives consistent earth-bonding resistance below 1 ohm with appropriate flange gasket selection. The SBAL-V auto duct line with stainless option produces 316L rectangular duct at 4–6 m/min on 1.0 mm gauge; the SBFB-1500 spiral tubeformer produces 316L round duct from 80 mm to 1500 mm diameter; the SBSF-1525 longitudinal stitch welder lays a continuous TIG bead on the lock seam for hermetic chemical-fume service.

4.3 309/310S high-temperature stainless and Inconel 625

For exhaust temperatures above 600 °C continuous — HIP cycle vent, atomisation tower exhaust, stress-relief oven exhaust above 600 °C — 316L exceeds its safe service temperature and creep deformation becomes a concern. 309/310S high-temperature stainless (Cr 22–25%, Ni 12–20%) extends service to 1100 °C continuous. Inconel 625 (Ni-base superalloy, Ni 58%, Cr 20–23%, Mo 8–10%, Nb+Ta 3.15–4.15%) extends further to 1200 °C continuous with excellent oxidation resistance. The SBPC1500 plasma cutter handles both alloys up to 25 mm thickness; the SB-ZF1500 longitudinal stitch welder deposits ER309L or ERNiCrMo-3 filler on the matching alloy seam. The first 3–5 m of any HIP cycle vent or atomisation exhaust is built in 309/310S or Inconel 625 with bellows expansion joints sized for the thermal growth (a 30 m run of 309/310S expands ~300 mm between ambient and 1000 °C).

4.4 Aluminised steel — medium-temperature workhorse

Hot-dip aluminised steel — carbon steel coated with an aluminium-silicon alloy — serves the medium-temperature AM exhaust between the high-temperature stainless section and the wet-bath collector or scrubber inlet. Service temperature 400–600 °C, good corrosion resistance to mildly acidic exhaust, good abrasion resistance. Aluminised steel is significantly cheaper than 316L stainless and is the practical choice for the bulk-length of HIP exhaust mains downstream of the stainless transition.

4.5 FRP fibreglass-reinforced plastic — HF acid etch service

For HF-bearing exhaust streams (titanium pre-paint etch, aluminium chemical etch), even 316L stainless is attacked slowly — FRP fibreglass-reinforced plastic with a corrosion-resistant resin (vinyl ester or furan) is the preferred material. FRP duct is built to AS/NZS 4254 with manufacturer-specific pressure and temperature ratings, with conductive interior coating where AS/NZS 60079 hazardous-area zoning is in effect.

5. Velocity and sizing — transport and capture for AM dust and fume

AM HVAC sizing is dominated by two velocity calculations — capture velocity at the contaminant source, and transport velocity in the main carrying contaminant to the collector. Both are driven by the contaminant chemistry, particle size and density, and the practical limits of fan static-pressure capacity.

Capture velocity at the source is set by the velocity at which the contaminant can be drawn away from the operator’s breathing zone faster than thermal buoyancy, mechanical disturbance and cross-drafts can carry it past. For metal-powder handling (depowdering, sieving, recycling), 0.5–1.0 m/s at the operator interface is the practical range; for welding fume (WAAM, post-process arc), 0.5–1.5 m/s at the arc; for photopolymer print cabinets, 0.3–0.5 m/s through the cabinet aperture; for SLS bead-blast cabinets, 0.5–0.7 m/s at the work aperture; for chemical-etch baths, 0.5–1.0 m/s across the bath surface.

Transport velocity in the main is set by the minimum velocity at which the contaminant remains entrained in the air stream without dropout. For metal powder (Ti, Al, Inconel, stainless, CoCr), 18–22 m/s is the standard range — below 15 m/s, fine powder begins to drop out at horizontal elbows and accumulates as combustible deposit. For polymer SLS powder, 15–20 m/s. For welding fume and metallic particulate, 15–20 m/s. For VOC vapour and ozone, 5–10 m/s is adequate (no particulate dropout concern). For chemical-etch acid mist, 10–15 m/s (corrosive but not abrasive). Each branch is sized at its design transport velocity; the main is sized for the simultaneous load of all branches at their design coincidence factor.

6. Cleanroom HVAC for medical and aerospace AM — ISO 14644

Medical AM (Stryker, Medtronic, Cochlear, Materialise) and the highest tier of aerospace AM (Amaero International for flight-critical components) operate in ISO 14644 cleanrooms. The classification system runs from ISO Class 1 (the cleanest, never used in AM) through ISO Class 9 (essentially room air). The medical and aerospace AM relevant range is ISO Class 5 (100 particles 0.5 µm per cubic foot, equivalent to US FED-STD-209E Class 100) through ISO Class 8 (3,520,000 particles per cubic foot, Class 100,000).

Stryker and Medtronic typically run the implant-cleaning and packaging area at ISO Class 5 with full laminar-flow ceiling, and the AM print room at ISO Class 7 or 8. Materialise operates Class 7 cleanrooms in the medical Sydney and Melbourne service centres. Amaero International runs aerospace production cells at ISO Class 8 for the bulk of the AM operation, stepping up to Class 7 for flight-critical assembly cells. The HVAC envelope sizing is dominated by air changes per hour (ACH) — Class 5 requires 240–360 ACH unidirectional flow; Class 7 requires 30–60 ACH with terminal HEPA filtration; Class 8 requires 5–48 ACH.

Supply-air mains are 316L stainless throughout with continuously TIG-welded longitudinal seam (SBSF-1525), HEPA polish at every terminal diffuser (typically 0.3 µm at 99.997% efficiency for Class 7; 0.12 µm ULPA at 99.999995% for Class 5). Exhaust mains are 316L stainless with welded longitudinal seam, with low-leakage isolation dampers at the cleanroom envelope boundary to maintain positive pressure +10 to +25 Pa relative to adjacent corridors. Cleanability of the cleanroom ductwork is the dominant material-selection driver — 316L stainless is the only practical choice for the cleanroom envelope.

7. Inert gas handling — argon, nitrogen, helium and asphyxiation

SLM, DMLS, EBM, HIP, atomisation, cold spray and heat-treatment all use inert gas at significant volume. Argon is the dominant inert gas in metal AM (Ti, Inconel, CoCr, stainless powder bed fusion requires Ar typically <0.5% O2 inside the chamber). Nitrogen substitutes for argon in some aluminium AM applications and in some cold spray installations (cheaper than Ar). Helium serves cold spray and some heat-treat atmospheres where its faster thermal response is valuable. All three gases are simple asphyxiants — non-toxic in themselves but displacing oxygen below the breathing-air threshold of 19.5% causes rapid unconsciousness without warning.

The HVAC engineering response to inert gas asphyxiation is engineered separation. The bulk gas storage (typically a 30,000 L cryogenic LAr or LN2 tank outside the building) is in an unoccupied exterior compound with prevailing-wind dispersion. The vapouriser, regulator and distribution piping are in 316L stainless to a manifold inside the building. The machine plenum (where the gas enters the AM build chamber) is fitted with O2 sensor at the operator-zone breathing height (cap 19.5–23.5%) and interlocked door access. Chamber vent during build-end and depowdering operations is captured at floor level (Ar is heavier than air, falls) into a 316L stainless 300–500 mm vent main at 5–10 m/s capture velocity, discharged to the building general exhaust at a height where the operator zone is not affected.

Confined-space entry permits per AS 2865 apply to any entry into a vessel that has held inert gas — HIP vessel for refractory inspection or maintenance, SLM chamber for cleaning between alloy changes, atomisation tower interior. Pre-entry purge to atmospheric air, continuous O2 monitoring, attended access and emergency rescue capability are mandatory.

8. Australian operator deep dives

8.1 Amaero International ASX:3DA — Notting Hill VIC, aerospace metal AM

Amaero International ASX:3DA is the country’s largest aerospace metal AM operator. Based in Notting Hill VIC, Amaero began as a Monash University spin-out in 2013 and listed on the ASX in 2021. The facility runs the largest installed base of EOS, SLM Solutions and TRUMPF SLM/DMLS machines in Australia, plus in-house gas atomisation capacity for proprietary Ti-6Al-4V (ASTM F2924) and Inconel 718 (F3055) feedstock production. Customers include Hypersonix Launch Systems (scramjet engine components), the Department of Defence DSTG, the Royal Australian Air Force aerospace supply chain, and SPEE3D for cold-spray-supplied components.

The HVAC stack at Amaero combines large-volume argon make-up (60,000+ L LAr stored outdoors in cryogenic vessel with vapouriser bank), the country’s biggest single AM-dedicated wet-bath dust collector serving multiple SLM cells in parallel at 15,000+ m³/h, 316L stainless powder handling and atomisation duct throughout the production zone, HIP and heat-treat oven exhaust through dedicated 309/310S stainless mains, post-process CNC and finishing LEV, NDT including industrial CT scan in a dedicated lead-shielded room, and aerospace AS 9100 + NADCAP audit-documented duct fabrication paperwork tying every metre back to its mill certificate.

The SBKJ machine fit at Amaero International is centred on the SBAL-V (316L cleanroom supply and exhaust), SBFB-1500 (spiral powder dust mains 200–1500 mm), SB-ZF1500 (continuous longitudinal stitch on the spiral powder mains), SBSF-1525 (cleanroom and chemical-fume hermetic seam), and SBPC1500 (HIP and atomisation transitions in 309/310S and Inconel 625). The SBAL-III + SB-ZF1500 covers the heavy-gauge 1.6–2.0 mm aluminised steel for HIP downstream exhaust.

8.2 AML3D ASX:AL3 — Adelaide WAAM submarine and defence

AML3D ASX:AL3 (Adelaide, with second hub at the Stem Cell Park production complex) is Australia’s largest wire arc additive manufacturing operator. The company began as a University of Wollongong R&D program (founder Andy Sales) and grew into a listed defence supplier producing submarine pressure-hull, propulsion and structural components for HMAS Stirling, Anduril Australia structural and aerospace components, and broader Department of Defence work. AML3D operates the country’s biggest installed base of WAAM cells with multiple ABB and KUKA robotic arms running MIG and TIG arcs across stainless 316L, Inconel 625/718, titanium Ti-6Al-4V, copper alloys, mild steel and tool steel.

The HVAC stack at AML3D combines overhead canopy WAAM-cell extraction (1.5–2.5 m/s capture at the arc with high-volume low-velocity HVLV systems), on-tool fume extraction at each welding torch, dedicated 316L stainless mains at 18–22 m/s transport into a multi-cell baghouse with HEPA polish, Cr VI continuous emissions monitoring at the stack discharge per EPA SA licence, and post-process CNC machining mist and dust capture.

The SBKJ machine fit at AML3D is centred on the SBAL-III heavy-gauge auto duct line (1.6–2.0 mm aluminised and 316L stainless for the WAAM canopy and baghouse-inlet mains), SBFB-1500 spiral (round mains for the trunk to the baghouse), SBSF-1525 longitudinal stitch (continuous seam for Cr VI hermetic service), and SBPC1500 plasma cutter (custom canopy hood geometry over the various robotic-cell footprints).

8.3 Titomic ASX:TTT — Notting Hill VIC, cold spray defence and aerospace

Titomic ASX:TTT at Notting Hill VIC is Australia’s flagship commercial cold-spray AM operator. The company commercialises CSIRO-licensed cold-spray technology for large-format titanium, copper, stainless and aluminium parts. Customers include Boeing, Lockheed Martin, the Australian and US Department of Defence, and a growing aerospace supply-chain customer base. The Titomic Kinetic Fusion platform produces parts up to 9 m long in titanium and copper.

The HVAC envelope at Titomic is dominated by nitrogen propellant exhaust (continuous 4000–8000 m³/h N2 release from the spray booth), rebound titanium powder capture (NFPA 484 Class D wet-bath collection), and operator-zone O2 monitoring at the booth exterior (cap 19.5–23.5%). AS 2865 confined-space entry permit governs any operator entry into the booth.

The SBKJ machine fit at Titomic centres on the SBFB-1500 spiral for the 316L stainless rebound-powder dust mains, the SBSF-1525 for continuous TIG seam on the powder mains, the SBAL-III for the heavy-gauge booth-exhaust transitions, and the SBPC1500 for custom booth-geometry transitions.

8.4 SPEE3D — Darwin NT, field-deployable cold spray defence

SPEE3D in Darwin NT is the country’s field-deployable cold-spray AM operator. The WarpSPEE3D portable cold-spray unit was developed for in-field defence vehicle repair at remote bases, with primary customers being Hypersonix Launch Systems, the Australian National University, the Department of Defence DSTG, and the Royal Australian Navy. SPEE3D’s technology supports rapid production of large-format metal parts in titanium, aluminium and copper.

The HVAC envelope at SPEE3D’s Darwin facility supports cold-spray production cells with N2 and Ar propellant exhaust, rebound powder capture and operator-zone O2 monitoring. The Darwin tropical climate adds humidity-control demand on the cleanroom and the powder-storage hopper (powder absorbs moisture and degrades flowability if humidity exceeds 30% RH at storage).

8.5 Aurora Labs ASX:A3D — Mt Marshall WA, large-format metal AM

Aurora Labs ASX:A3D at Mt Marshall WA develops large-format metal powder bed fusion printers targeting single-machine throughput an order of magnitude above conventional SLM. The Multilevel Concurrent Printing (MCP) technology stacks multiple layers in parallel inside the build chamber. Customers and pilot installations cover mining, defence and aerospace applications.

The HVAC envelope at Aurora Labs combines high-volume argon make-up for the large-chamber MCP system, powder-handling NFPA 484 Class D dust collection, and post-process CNC and finishing LEV. The remote WA location adds logistics-cost considerations for bulk gas supply.

8.6 Stryker, Medtronic, Cochlear, Materialise — medical AM

Stryker Australia, Medtronic Australia, Cochlear and Materialise Australia all operate dedicated medical AM cells under TGA TGO 92 and ISO 13485. Stryker 3D-prints orthopaedic and cranial implants in CoCr (F3213) and Ti-6Al-4V ELI (F3001) at Sydney and Melbourne facilities. Medtronic 3D-prints surgical instruments, craniofacial implants and patient-specific guides in titanium, stainless and PEEK at Macquarie Park NSW. Cochlear at Macquarie University NSW 3D-prints cochlear-implant electrode-array components in biocompatible materials. Materialise Australia’s Sydney and Melbourne service centres cover dental implants (titanium and CoCr), craniofacial implants (titanium and PEEK), orthopaedic prototypes (PA12 and titanium) and patient-specific surgical guides (PA12 and resin).

The HVAC stack at each medical AM operator is dominated by ISO 14644 cleanroom envelopes (Class 7 or Class 5 depending on operation), 316L stainless ductwork throughout, hermetic continuous-seam welded construction (SBSF-1525 + SB-ZF1500), full TGA TGO 92 documentation tying every duct length to its mill certificate and pressure-test record, and VHP/formaldehyde decontamination compatibility on every component.

8.7 Bastion Cycles — Melbourne titanium 3D-printed bicycle

Bastion Cycles in Melbourne produces the world’s premium titanium 3D-printed bicycle frame — titanium AM lug components joined to carbon-fibre composite frame tubes, customised per rider geometry. The production process uses SLM/DMLS Ti-6Al-4V (ASTM F2924) at small scale, with the AM cell operating under the same NFPA 484 + AS/NZS 60079 + ASTM standards as larger aerospace operators — just at smaller throughput. Bastion represents the small-business end of the Australian aerospace-grade titanium AM sector.

8.8 Luyten 3D — concrete 3D printing Sydney, Melbourne and SA

Luyten 3D is Australia’s first commercial concrete 3D printing operator, with sites in Sydney, Melbourne and South Australia. The technology uses a large-format gantry or robotic-arm extruder to deposit a Portland-cement, fly-ash, aggregate and admixture mix to build walls, columns, formwork and architectural elements. The HVAC envelope is dominated by RCS dust control (0.05 mg/m³ WES) at every dry-material handling station, with 316L or aluminised steel LEV mains at 18–22 m/s transport into a baghouse with cyclone pre-separation.

8.9 CSIRO Lab22, ANU, Monash, USyd, RMIT, UoW, Adelaide, Swinburne — research AM

CSIRO Lab22 at Clayton VIC is Australia’s national additive manufacturing research facility, with parallel installations at ANU, Monash, the University of Sydney, RMIT, the University of Wollongong, the University of Adelaide and Swinburne. Lab22 runs SLM, EBM, WAAM, cold spray, atomisation, polymer SLS, SLA and FDM at research scale. The HVAC envelope spans the full sector demand at lower production volumes — every standard listed in this guide applies, just with smaller infrastructure footprint. CSIRO Lab22 collaborates with the commercial operators (Amaero, AML3D, Titomic, SPEE3D, Aurora Labs) on process development and material qualification.

9. Fabrication procedures and SBKJ machine application

Fabricating AM-grade ductwork in an Australian shop requires the right machine fit, the right process discipline, and the right documentation. The SBKJ Product Catalog 2026 covers the full envelope for AM duct fabrication:

SBAL-V — auto duct line with stainless option, handling galvanised and 304/316L stainless from 0.7 mm to 1.6 mm. Production rate 4–10 m/min depending on gauge and material. Used for the bulk of supply and general extract ductwork plus the 316L cleanroom envelope for medical and aerospace AM.

SBAL-III — heavy-gauge auto duct line for 1.6–2.0 mm work. Production rate 8–12 m/min depending on gauge. Used for HIP and heat-treat downstream exhaust, large baghouse-inlet mains, and WAAM canopy structures.

SBSF-1525 — longitudinal stitch welder for continuous TIG seam on the lock-seam joint. Travel speed 600–900 mm/min on 1.2 mm 316L with argon shield gas at 12 L/min. Used for cleanroom envelopes, chemical-fume mains and any duct requiring hermetic seam.

SB-ZF1500 — longitudinal stitch welder for trunk-main continuous TIG seam, in-line with the SBFB-1500 spiral former. Used for NFPA 484 combustible-metal powder mains and chemical-fume mains above 1000 mm diameter.

SBFB-1500 — spiral tubeformer producing spiral round duct 80–1500 mm diameter in 0.6–1.5 mm galvanised, aluminised or stainless. Production rate 3–6 m/min on 1.2 mm 316L 800 mm diameter. Used for powder dust mains, rebound powder capture from cold spray, polymer SLS dust extraction and post-process CNC dust extraction.

SBPC1500 — plasma cutter handling stainless and Inconel up to 25 mm thickness with HD plasma quality. Production rate 1.2 m/min on 1.5 mm 316L, 0.8 m/min on 1.5 mm Inconel 625. Used for custom transitions, refractory-anchor stud plates, HIP cycle vent flanges and atomisation tower transitions.

SBLR-600 — lock former producing Pittsburgh lock and snap-lock longitudinal seams. Used for rectangular duct construction with the heavy-gauge tooling set for 1.2 mm 316L cleanroom and chemical-fume service.

SBTF-1500/1602/2020 — spiral former family for trunk mains 1500–2000 mm diameter. Used for centralised powder-recycling and atomisation feed circuits, large-format AM dust trunk mains, and cleanroom supply trunk mains at the highest-volume installations.

10. Commissioning, monitoring and AS/NZS compliance

Commissioning AM ductwork is more demanding than commissioning conventional industrial HVAC. The compliance documentation required at handover includes pressure-test records (1.5x design pressure for 30 minutes per AS 4254), earth-bonding verification at every flange (resistance below 1 ohm to ground), conductivity verification on every conductive flexible connection, NATA-certified airflow balance against design schedule, NFPA 484 dust hazard analysis tied to AS 3957 zoning, AS/NZS 60079.10 zone-classification document, ASTM F2924/F3001/etc material-traceability paperwork tying powder feedstock through the duct path, and (for medical or aerospace work) TGA TGO 92 or AS 9100/NADCAP audit-ready documentation.

Ongoing monitoring runs daily, weekly, monthly and annual cycles. Daily: O2 monitoring at the operator interface (continuous, alarm at 19.5% and 23.5%), pressure differential across the wet-bath collector (alarm at +/- 25% design), particulate concentration at the discharge stack (continuous PM2.5 and PM10 monitoring per state EPA licence). Weekly: visual inspection of duct interior at access ports for powder accumulation, condition of bonding straps, condition of ATEX-rated flange gaskets. Monthly: airflow balance verification at key branches, isolation-valve actuation test, fan-vibration measurement. Quarterly: NATA-certified breathing-zone air sampling against WES for every operator-occupied zone, with the data fed into the AS 4801/ISO 45001 OHS management system. Annual: full system pressure test, full bonding-resistance re-verification, refractory inspection at high-temperature exhaust sections, wet-bath collector liquid replacement and cleaning, ATEX equipment inspection per AS/NZS 60079.17.

11. Future trends and the AM duct fabrication outlook

The Australian additive manufacturing sector is on a fast-growth trajectory. Defence and aerospace AM is increasing in volume on the back of submarine, hypersonic and uncrewed-aerial-vehicle programs. Medical AM is increasing on the back of patient-specific implant adoption. Cold spray is expanding into field-deployable defence applications. Concrete 3D printing is emerging as a building-construction technology. Each segment drives demand for new AM facilities, expanded existing facilities and replacement of ageing first-generation HVAC infrastructure.

Four trends will shape the next decade. First, polymer AM at production scale — HP Multi Jet Fusion, Stratasys and Carbon are driving polymer AM towards injection-moulding-replacement volumes, with corresponding scale-up of polymer-dust LEV. Second, copper and aluminium AM at scale for electric-vehicle motor windings and heat exchangers — the rise of copper PBF (now achievable with green-laser machines and electron-beam) drives new powder-handling demand. Third, hybrid manufacturing — combined AM + CNC machining in a single cell, used at Velo3D, DMG Mori and Mazak hybrid systems, with corresponding integration of dust and mist capture circuits. Fourth, sustainable AM — recycled powder, lower-energy lasers, recycled photopolymer resin streams, and the corresponding stack-emissions licence tightening from state EPAs.

Every trend feeds back to ductwork demand. New facilities, expanded facilities and replacement infrastructure all require AS/NZS 60079 zoned, NFPA 484 compliant, 316L stainless ductwork fabricated to AS 4254 with continuous earth bonding, hermetic seam where required, and documented traceability through to powder feedstock and end-use part. SBKJ’s 2026 catalog and engineering support is positioned to serve this market across Australia — from the established Notting Hill VIC AM cluster (Amaero, Titomic) to Adelaide (AML3D), Darwin (SPEE3D), WA (Aurora Labs), and the medical clusters in Sydney (Stryker, Medtronic, Cochlear) and Melbourne (Materialise, Bastion Cycles, CSIRO Lab22).

12. Industry bodies and standards organisations

The Australian AM sector is supported by an active set of industry bodies and standards organisations. The Additive Manufacturing Industry of Australia (AMIA) is the peak national body covering commercial AM operators, machine vendors and material suppliers. The Advanced Manufacturing Growth Centre (AMGC) is the federal Department of Industry Science Energy and Resources (DISR) initiative supporting advanced-manufacturing capability across multiple sectors including AM. AiGroup represents broader Australian manufacturing including AM. The Australian Additive Manufacturing Cooperative (AAMC) coordinates research and commercial AM linkages. AMTIL serves machine-tool and AM equipment dealers. CSIRO Lab22 is the national research AM facility. The ARC Manufacturing Centre at Monash University and parallel ARC centres at other universities run research-grade AM programs. The Australian Defence Industry Council and the Defence Innovation Hub fund defence AM development. DSTG (Defence Science and Technology Group) operates research AM internally and contracts work to AML3D, Amaero, Titomic and SPEE3D.

Standards bodies include Standards Australia (the AS/NZS standards publisher), ASTM International and ISO (jointly publishing the ISO/ASTM 52900 series and the individual material standards F2924, F3001 etc), SAE International (publishing the AMS aerospace materials standards including titanium and Inconel AM specifications), the Therapeutic Goods Administration (TGA, biomedical regulation), the Civil Aviation Safety Authority (CASA, aerospace certification), the Federal Aviation Administration (FAA, US aerospace certification flow-down), and the European Union Aviation Safety Agency (EASA, EU aerospace certification flow-down).

13. SBKJ machine application checklist for AM duct fabrication

For an Australian fabricator serving the AM sector from Box Hill North VIC, the practical SBKJ machine envelope to cover the full AM duct demand is:

• SBAL-V with 316L stainless option — supply-air and general extract for ISO 14644 cleanrooms, medical AM Stryker/Medtronic/Cochlear/Materialise, aerospace AM Amaero, and the 316L bulk of any AM facility. Production envelope 0.7–1.6 mm 304/316L plus galvanised and aluminised.
• SBAL-III — heavy-gauge 1.6–2.0 mm work for HIP, heat-treat oven and atomisation downstream exhaust, plus WAAM canopy at AML3D and Cr VI dedicated baghouse-inlet mains.
• SBSF-1525 — continuous TIG longitudinal seam for cleanroom hermetic envelope, NFPA 484 combustible-metal mains and chemical-fume mains. Critical for medical AM TGA TGO 92 documentation.
• SB-ZF1500 — in-line continuous longitudinal seam on spiral mains 1000–1500 mm. Used at every AM operator handling powder above 200 kg in active circulation.
• SBFB-1500 — spiral round duct 80–1500 mm diameter for powder dust mains, polymer SLS dust mains, cold spray rebound capture, and post-process CNC dust capture. The single most-used machine for AM duct fabrication.
• SBPC1500 — plasma cutter for custom transitions in 316L, 309/310S and Inconel 625. Used for HIP cycle vent transitions, atomisation tower transitions, WAAM canopy custom geometry and refractory-anchor stud plates.
• SBLR-600 — lock former for Pittsburgh lock and snap-lock seams in rectangular duct. Heavy-gauge tooling for 1.2 mm 316L cleanroom and chemical-fume service.
• SBTF-1500/1602/2020 — spiral trunk mains 1500–2000 mm for centralised powder-recycling, atomisation feed circuits and cleanroom supply trunk mains.

The combined machine fit delivers the production envelope to cover every duct requirement across every Australian AM operator from Amaero International in Notting Hill VIC, AML3D in Adelaide, Titomic in Notting Hill, SPEE3D in Darwin, Aurora Labs in Mt Marshall WA, Stryker in Sydney, Medtronic in Macquarie Park, Cochlear at Macquarie University, Materialise in Sydney/Melbourne, Bastion Cycles in Melbourne, Luyten 3D in Sydney/Melbourne/SA, and CSIRO Lab22 plus the broader university AM research network.

14. AS/NZS compliance checklist for AM duct fabrication and commissioning

A short-form compliance checklist for AM ductwork commissioning, suitable for inclusion in handover documentation:

• AS 1668.2 mechanical ventilation — design extract and make-up air calculations documented for every zone.
• AS 4254 sheet-metal duct construction — pressure-test certificates at 1.5x design pressure for 30 minutes on every duct branch.
• AS 1530.4 fire resistance — fire-rated penetrations certified at 250 °C/2 hour at every fire-compartment boundary.
• AS/NZS 60079.10 hazardous-area classification — documented Zone 20/21/22 (dust) and Zone 1/2 (gas) maps with electrical-equipment selection per AS/NZS 60079.0–.31.
• AS 3957 dust hazard areas — documented dust hazard analysis covering Kst, minimum ignition energy, and deflagration-protection chain.
• AS 1940 flammable and combustible liquids — IPA, acetone and other Class IB/IIIA storage documented and segregated.
• AS/NZS 1715 and 1716 respiratory protective equipment — PAPR and full-face respirator selection documented for every powder-handling task.
• AS/NZS 2982 fume cupboard — documented capture velocity and exhaust path for chemistry-lab and chemical-etch stations.
• AS 2865 confined-space entry — permit-to-work system in place for HIP vessel, SLM chamber and atomisation tower interior.
• AS 4036, AS 4458, AS 3920, AS/NZS 1200 — HIP pressure-vessel registration and inspection documentation.
• AS/NZS 4453 welding-fume control — documented on-tool extraction and local exhaust at WAAM cells, post-process welding and casting repair.
• AS 4801 / ISO 45001 OHS management — documented LEV maintenance records, breathing-zone air-sampling data quarterly per WES.
• NFPA 484 combustible metals — wet-bath collection documented for Ti, Al, Mg fines with explosion-isolation valves between baghouse and inbound duct.
• NFPA 660 (2025) consolidated dust — facility-wide dust hazard analysis updated to NFPA 660 requirements.
• NFPA 86 industrial ovens — LEL monitoring, purge cycle and burner management system on every fuel-fired HIP, stress-relief and atomisation system.
• NFPA 68 deflagration venting and NFPA 69 inerting — documented for every combustible-dust collection system.
• ASTM F2924, F3001, F3055, F3056, F3318, F3184, F3213 — powder feedstock traceability tied through HVAC infrastructure for aerospace and medical AM.
• ISO/ASTM 52900–52950 — AM process and quality documentation including ventilation infrastructure per ISO/ASTM 52920.
• AS 9100 + NADCAP AC7110/14 — aerospace audit-ready documentation for Amaero, AML3D, Titomic, SPEE3D, Aurora Labs and Quickstep production cells.
• ISO 13485 + TGA TGO 92 — medical-device manufacturing documentation for Stryker, Medtronic, Cochlear, Materialise and dental AM operators.
• ARPANSA RPS 1 — ionising radiation safety for industrial CT scan and EBM rooms.
• NATA certification — final commissioning balance and breathing-zone sampling certified by NATA-accredited laboratory.

Compliance documentation forms the bridge between the fabricated ductwork and the operator’s ongoing regulatory obligation. Every length of ductwork SBKJ supplies to an Australian AM fabricator is delivered with mill certificate, fabrication date, pressure-test record, earth-bonding verification at every flange, and AS/NZS-compliant labelling on every section — the foundation paperwork that the AM operator then integrates into the AS 9100, ISO 13485, NADCAP or TGA audit pack.

15. Closing — SBKJ engineering support for Australian AM

The Australian additive manufacturing sector is moving from research-pilot scale to industrial-production scale across multiple verticals simultaneously — aerospace, defence, medical, automotive, construction and consumer product. Every transition from pilot to production exposes the limits of generic commercial HVAC and demands purpose-engineered ductwork that meets the full standards stack outlined in this guide. The SBKJ Group engineering team in Box Hill North VIC is positioned to support Australian fabricators serving the AM sector with a combination of machine supply (SBAL-V, SBAL-III, SBSF-1525, SB-ZF1500, SBFB-1500, SBPC1500, SBLR-600, SBTF-1500/1602/2020), engineering documentation, commissioning support, and ongoing technical advisory across every AM process zone described in this document.

We will be exhibiting at ARBS 2026 in Sydney in May with the full SBKJ machine portfolio plus AM-specific reference samples covering 316L cleanroom envelope, NFPA 484 combustible-metal spiral, HIP and heat-treat oven transitions, and chemical-etch FRP integration. Pre-show meetings with Australian AM fabricators, machine OEM partners and existing customers are scheduled across the week.