Australia Post, Parcel, Courier, Last-Mile & E-Commerce Fulfilment HVAC Ductwork Guide

Why parcel logistics is the fastest-growing HVAC duct segment in Australia

If you stand on the roof of an industrial estate in Truganina (west of Melbourne), Eastern Creek (west of Sydney) or Larapinta (south of Brisbane) and look across the floor plates under construction in 2026, you are looking at the Australian parcel and e-commerce fulfilment build-out. The federal government's e-commerce penetration data crossed 18 percent of total retail sales in 2025 and is forecast at 22–24 percent by 2030. Australia Post processed 528 million parcels in 2024 and is on track for 620 million in 2026, with the network of 200-plus parcel centres, 25 Letter Centres and 4,400-plus retail outlets all under either active modernisation or greenfield build. StarTrack (Australia Post Group's express parcel arm), TOLL Group (owned by Japan Post), DHL Express Australia, FedEx Express Australia, UPS Australia, Aramex Global Express (the rebranded Fastway), Couriers Please (Singapore Post), Sendle, Hubbed, Pickup Pak and the major retailer fulfilment arms (Woolworths X automated by Witron Logistik, Coles online on Ocado technology, Amazon Australia with four hyperscale fulfilment centres, eBay, THE ICONIC, Catch, Kogan, Officeworks, JB Hi-Fi, Bunnings Online, IKEA, Temple & Webster, Adore Beauty, Cettire, Booktopia) are all expanding floor plates simultaneously.

From an HVAC engineering standpoint, this segment looks superficially like a distribution warehouse — large floor plate, low occupancy on the bulk floor, high occupancy at the pick and pack stations, large dock arrays at low level, a small office block at the front. But it differs from a conventional distribution warehouse in seven material ways. First, it runs 24/7 with the inbound peak at 02:00 to 06:00 from upstream trunk delivery, which means the HVAC has to cope with summer overnight ambient still at 28–32°C. Second, the automated cross-belt and tilt-tray sorter loops introduce a continuous high-density heat load that no conventional warehouse contains — 80–250 kW dissipated across the sorter footprint, rising as a buoyant plume to the apex. Third, the air mail security zone introduces an ICAO Annex 17 and Aviation Transport Security Act 2004 pressure-relationship requirement that no conventional warehouse has. Fourth, the dangerous goods consignment cell introduces a hazardous-zone classification under AS/NZS 60079. Fifth, the cold-chain parcel handling segment introduces refrigerated handling at 2–8°C chilled and minus 18 to minus 22°C frozen inside a building that is otherwise ambient. Sixth, the EV delivery van charging zone introduces stationary BESS, AS/NZS 5139 plus NFPA 855 controls, and AS 4214 gaseous suppression. Seventh, the network density means the project is repeated 50–100 times across the major REIT portfolios over the period 2024 to 2030, so duct contractors who get the spec right once can productise the package across the segment.

This guide is written for the consulting engineers, design-and-construct contractors, head contractors, HVAC ductwork subcontractors and the parcel and fulfilment operators specifying, producing and commissioning ducts on these projects. It assembles the code stack, the climate envelope, the zoning logic, the duct sizing approach, the sorter-loop heat-extract design, the air mail security HVAC, the dangerous goods cell ventilation, the cold-chain handling boundaries, the EV charging and BESS room ventilation, the operator-specific notes for the major Australian operators, and the SBKJ machine configuration that produces the necessary ductwork mix at scale from our Box Hill North VIC engineering office.

Code stack — what governs HVAC duct design in an Australian parcel facility

The applicable code stack for an Australian parcel sortation centre, courier hub, last-mile depot or e-commerce fulfilment centre is unusually dense because of the air cargo security, dangerous goods, hazardous area, customer-data and 24/7 occupancy overlays. Here is the working list our engineers run through on every parcel-sector HVAC review:

• NCC (National Construction Code) Volume One — classifies the building. Bulk parcel handling and storage is Class 7b. The conveyor and sorter plant rooms with continuous motor heat and minor maintenance are Class 8 industrial. The administration block at the front is Class 5 office. The public retail counter (Australia Post Retail Outlets, LPOs and CPAs) is Class 6.
• AS 1668.1 — mechanical smoke management. Applies to the bulk sortation hall and the office block. Prescribes powered smoke exhaust at the roof apex sized to maintain a smoke-free layer above the highest sprinkler head, integrated with sprinkler activation under AS 2118 and detection under AS 1670.
• AS 1668.2 — outdoor air for general ventilation. Sets the outdoor air rate per zone — typically 0.4–0.6 L/s/m² for bulk sortation, 10 L/s/person at induction and manual sort stations, elevated rates at inbound truck unloading dock (diesel particulate matter EC 0.1 mg/m³, CO 30 ppm, NO2 5 ppm STEL).
• AS 4254 — ductwork for air-handling systems. Sets leakage class (A, B, C, D), reinforcement, joint construction and sealing requirements. Class C minimum (under 4 percent leakage at design pressure) is the working benchmark for NABERS-rated builds.
• AS 1530.4 — fire-resistance testing of ductwork. Applies to fire-rated penetrations and smoke spill duct.
• AS 1851 — routine service of fire protection systems and equipment. Applies to fire dampers, smoke control fans and air-handling unit fire-mode coordination through the operational life of the facility.
• AS/NZS 60079 — explosive atmospheres. Applies to forklift charging rooms (hydrogen evolution), hydrogen fuel-cell forklift dispensing zones, LPG forklift refuelling under AS 5601, the dangerous goods consignment cell, the BESS room, and the backup generator fuel storage if co-located. Drives spark-resistant duct construction and explosion-protected fan selection across all of these zones.
• AS 1940 — storage and handling of flammable and combustible liquids. Applies to the dangerous goods cell where Class 3 flammable liquid parcels are held.
• AS/NZS 5139 and NFPA 855 — safety of battery systems for use with power conversion equipment, and stationary energy storage systems. Apply to BESS rooms for grid-connected battery storage co-located with rooftop solar PV, and increasingly to EV delivery van charging zones where the bay houses both charging power electronics and battery thermal management.
• AS 4214 — gaseous fire-extinguishing systems. Applies to the BESS room, the IT data centre, the dangerous goods cell and the records-archive zone where a sprinkler is unacceptable.
• AS 2118 — sprinkler systems for general applications. Applies across the bulk sortation hall, with in-rack arrangements for high-density storage and ESFR for tall stack heights.
• AS 1670 — fire detection, warning, control and intercom systems. Applies across the building with sortation-hall specific coverage for the cross-belt sorter loop heat detection.
• AS 4072.1 and AS 4072.3 — service penetrations through fire-rated barriers, and integrity testing of fire-rated penetration systems. Apply to every duct penetration through a fire-rated wall or floor in the facility.
• AS 5601 — gas installations. Applies to LPG forklift refuelling stations on the depot floor.
• AS 3000 — wiring rules. Applies to all electrical equipment including the spark-resistant fan motors and the BESS room electrical infrastructure.
• ICAO Annex 17 — security: safeguarding international civil aviation against acts of unlawful interference. Applies to air mail at Australia Post Loop Sortation Centres in Sydney, Melbourne and Brisbane, and at courier express hubs at the Sydney, Melbourne, Brisbane and Perth airport mail facilities. Drives the four-tier security zoning of the air mail HVAC.
• ICAO Annex 18 — the safe transport of dangerous goods by air. Applies to the dangerous goods consignment cell when DG parcels are routed to air freight despatch.
• IATA Cargo Standards — operational standards for air cargo handling, including temperature controls for pharmaceutical and perishable shipments. Applies to cold-chain air freight handling.
• Aviation Transport Security Act 2004 — the Australian federal legislation that gives force to ICAO Annex 17. Air Cargo Security Programs under this Act define the known-consignor, regulated-air-cargo-agent and regulated-air-cargo-shipper roles, each with their own facility security and HVAC pressure-relationship implications.
• Australian Border Force regulations — apply to international inbound mail, customs inspection zones and bonded warehousing inside the major gateway sortation centres.
• AusPost service standards — Australia Post's own delivery service-level standards drive the 24/7 operational profile and inform the HVAC redundancy requirement (N+1 on the sortation-hall AHUs is the working benchmark to avoid service-standard breach during a unit failure).
• Australian Consumer Law — applies to the public retail counter customer interface.
• Privacy Act 1988 and the Australian Privacy Principles (APPs) — apply to customer data handling at the retail counter and in the office. Drives modest acoustic separation requirements at the customer-facing interface — sound attenuators in the supply duct to the counter and the queueing area.
• State environmental authorities — Victorian EPA, NSW EPA, QLD DES, WA DWER and equivalents. Apply to the discharge from the dangerous goods cell extract, the diesel truck unloading dock extract, the LPG forklift refuelling area, the BESS room gaseous suppression discharge and the backup generator stack.
• AS 1657 — fixed platforms, walkways, stairways and ladders. Applies to plant room access at roof level.
• AS 1742 — manual of uniform traffic control devices. Applies to truck and forklift movement signage at the depot, and indirectly to HVAC intake and discharge placement to avoid vehicle-exhaust ingestion.
• AS 1428.1 DDA — design for access and mobility. Applies to the public retail counter and the staff amenity areas.
• AS 1735 — lifts, escalators and moving walks. Applies to the goods lifts between despatch dock and mezzanine sort levels.
• ASHRAE 62.1 — ventilation for acceptable indoor air quality. Used as cross-reference on multinational fit-outs (Amazon, DHL, FedEx, UPS) and on projects led by US-based engineering consultancies.
• ASHRAE 90.1 — energy standard for buildings except low-rise residential. Used as cross-reference for fan-energy budgets and economy-cycle requirements on multinational fit-outs.
• NABERS for Industrial — voluntary energy and emissions rating that has expanded in recent years to cover logistics warehouses, refrigerated DCs and AS/RS sites. Standard tender requirement from Goodman, Charter Hall, ESR Australia, Logos and Centuria.
• Green Star — Industrial — Green Building Council of Australia rating tool for industrial buildings.

For full reference on AS 1668.2 outdoor air calculations across building classes, see our companion AS 1668.2 Australian Ventilation Code Reference. For ductwork construction detail, see the AS 4254 Australian Ductwork Construction Reference. The remainder of this guide assumes the reader is broadly familiar with these and focuses on how the code stack is applied to parcel logistics and e-commerce fulfilment.

Climate — designing for 24/7 operation across Australian extremes

The Australian climate envelope is the second-most-cited reason large-floor-plate parcel facilities differ from European or North American equivalents — and it is amplified for parcel because the operating profile is 24/7, not 14/5. Across the Australian Building Codes Board climate zones, summer 99 percent peak design temperature ranges from 32°C in Hobart to 45°C in inland NSW and WA, with humidity loads in zones 1 and 2 (Darwin, Brisbane, Townsville) adding 10–18 g/kg moisture content on a typical summer afternoon. But the parcel-sector design point is not just the daytime peak. It is the overnight summer ambient — still 28–32°C at 03:00 in Melbourne and Sydney on a heatwave night, when the inbound trunk-delivery peak is hitting the dock — and the winter early morning lows that drive heating load at the same 02:00 to 06:00 inbound peak when warehouse activity is at its highest.

The practical consequence is that the HVAC system never gets a quiet period to coast. Conventional distribution warehouse design that runs heating-and-cooling on a single-shift operational profile (08:00 to 18:00) can use overnight thermal flywheel and morning warm-up. A parcel sortation centre cannot — the building is in active operation every hour of every day of the year. The design points that cascade out of this:

• N+1 redundancy on every major AHU is the working benchmark. A single AHU failure during the 02:00 to 06:00 inbound peak risks breaching the AusPost service standard and triggering significant operational penalty. Eight AHUs at N+1 means nine units installed; ten AHUs at N+1 means eleven. Redundancy is more expensive on parcel than on conventional warehouse, but the operational cost of a failure justifies it.
• Air-side economy cycle is mandatory and works overtime. When the outdoor air falls below the indoor target temperature (overnight in shoulder seasons, through autumn and winter), economy cycle brings 100 percent outdoor air across the AHU coils. Typical Australian parcel sortation AHUs run economy cycle 4,500–5,500 hours per year — more than half the operating year, given the 24/7 profile.
• Solar PV roof integration is mandatory under the operator commitments. Australia Post's 2050 net-zero, the Linfox and Toll equivalents, the Coles and Woolworths emissions commitments, the major REIT requirements — all drive 10–25 kg/m² rooftop solar PV loading on new builds, generating 1.5–6 MW peak DC power on a 50,000–100,000 m² roof. The HVAC plant runs on the solar generation profile during the day, drawing from the grid only at peak summer load and overnight. A grid-connected BESS sized for 4–8 hours of operational HVAC load is increasingly common, which introduces the AS/NZS 5139 plus NFPA 855 implications discussed under code stack.
• Destratification fans are not optional. The 8–12°C floor-to-roof stratification on a hot summer afternoon means the racked stock at the top of the racking sees substantially hotter air than the picking face. HVLS destratification fans on 7–8 m diameter blades at roof level mix the column on demand and protect the upper-rack stock from heat damage. On a 60,000 m² site, expect 10–16 HVLS fans installed.
• The cross-belt sorter heat load is a continuous load, not a peak load. Unlike conventional warehouse HVAC where the dominant cooling load is solar gain through the roof (peaking 12:00 to 16:00), the parcel sortation centre has a continuous 80–250 kW heat load from the cross-belt sorter that runs 16 hours a day. This shifts the load profile and the AHU sizing — the dedicated sorter-loop AHU is sized for steady-state continuous duty, not summer peak.

Zoning — how to divide a 60,000 m² parcel sortation floor plate

Modern Australian parcel sortation centres are densely zoned — denser than conventional distribution warehouses because of the air cargo security, dangerous goods and cold-chain overlays. The typical zoning we see on a 60,000 m² floor plate at a major operator's hub is:

• Inbound truck unloading dock (5–8 percent of floor area). High air-leakage when roller doors open. Diesel particulate matter from arriving trucks. Design 10–15 ACH ducted extract at the dock face, captured at low level where the truck exhaust collects, with make-up air from the rear of the dock to drive a one-way flow from clean to contaminated.
• Parcel acceptance and DWS (dimensioning, weighing, scanning) (5–10 percent). Moderate occupancy with vision-system camera arrays and conveyor induction. Partial conditioning at 22°C with elevated outdoor air at the operator workstations.
• Automated sortation centre — cross-belt sorter loop, tilt-tray sorter, putwall, autobagger (30–45 percent on a hub of this scale). The dominant single zone in a modern parcel facility. Moderate occupant density at induction and discharge, very high motor heat density across the loop. Dedicated sorter-loop AHU sized for the 80–250 kW continuous heat load, with dropped supply terminals at induction and discharge stations and apex-extract directly above the loop. Major equipment vendors are Bastian Solutions, Dematic, SSI Schaefer, Vanderlande and TGW — each has their own equipment heat-rejection profile that drives the dedicated AHU sizing.
• Air mail sortation zone (only at major gateway centres — the Australia Post Loop Sortation Centres in Melbourne, Sydney and Brisbane, and the courier express hubs at the major airports). 5–15 percent of floor area depending on the international air freight volume. Four-tier security zoning under ICAO Annex 17 and the Aviation Transport Security Act 2004.
• Express courier hub zone (DHL Express, FedEx, UPS, TOLL Express, TOLL IPEC, TOLL Express Parcels, Aramex, StarTrack, Couriers Please, Sendle). 10–20 percent at courier-specific facilities, smaller at multi-operator hubs.
• Bulky goods sortation (large parcels, furniture, appliances — IKEA Australia, Officeworks, Bunnings Online, JB Hi-Fi). 5–15 percent at hubs handling bulky despatch. Larger conveyor segments, fewer sorter loops, larger pick face. Lower air change rate relative to floor area than the standard sortation zone because the throughput density is lower.
• Last-mile distribution despatch dock (5–10 percent). Outbound truck and van loading. High EV charging activity in the transition fleet. 8–12 ACH extract for diesel particulate matter from the legacy ICE fleet plus the EV charging zone ventilation requirements.
• Cold-chain parcel handling zone (where applicable — HelloFresh, Marley Spoon, Dinnerly, Coles online, Woolworths X, Australia Post Sameday medical and pharmaceutical, Aussie Fresh frozen seafood). 5–25 percent depending on the operator's cold-chain mix. Chilled handling at 2–8°C. Frozen handling at minus 18 to minus 22°C. Cross-reference the SBKJ Cold Storage & Cold Chain HVAC Duct Guide for the refrigeration plant, vapor barrier and dock-seal detail.
• Customs and Border Force inspection (international gateway centres only). Clean and secure controlled environment. Modest area (50–200 m²). Positive pressure relative to the surrounding zone.
• Dangerous goods consignment cell (1–3 percent depending on DG volume). Hazardous-zone enclosure under AS/NZS 60079 with continuous 10–15 ACH spark-resistant extract. Sub-compartmented by DG class.
• Hazmat decontamination cell (single small cell, 8–20 m²). Negative pressure HEPA single-pass extract for incoming-suspicious-package screening. Retained from the Anthrax-era postal security response and re-pressed into service for fentanyl and biological-agent containment in the 2020s.
• X-ray screening room (cargo inspection — federal Aviation Transport Security Act 2004 and Australian Border Force). 20–80 m² at major gateway sortation centres. Lead-shielded duct walls at the cabinet penetration.
• Conveyor maintenance shop (1–3 percent). Minor extract at the workbench, lift hoist for sorter-loop service access, ambient HVAC otherwise.
• Forklift charging room (1–3 percent). AS/NZS 60079 Zone 2 spark-resistant extract. Mix of lead-acid, lithium-ion and (at some operators) hydrogen fuel-cell forklifts.
• Driver crib room and rest area (1–3 percent). 24/7 shift operation. Staggered occupancy outdoor-air calculation under AS 1668.2.
• Letter sortation (legacy declining business — still significant at the 25 Australia Post Letter Centres). Lower air change rate, lower equipment density, mostly displaced by parcel volume in the operator's growth profile.
• Manual sortation and pre-sort area (1–10 percent at smaller centres without full automation). 10 L/s/person at the manual workstation.
• Mail bag handling, letter holding and overflow (1–5 percent). Ambient ventilation.
• Despatch hangar and aircraft loading (at the airport mail facilities — refer to the SBKJ Airport and Aviation HVAC Duct Guide for full detail on the airside HVAC).
• Office and admin (Australia Post HQ and regional, 3–8 percent). Separate VRF or rooftop packaged HVAC. Rectangular TDF-flanged duct.
• IT data centre (Australia Post Digital, Amazon Web Services co-located on the hyperscale fulfilment centres, the major operator IT rooms). 0.5–3 percent. Refer to the SBKJ data centre HVAC guide for detail.
• Public retail mail counter (at the integrated counter sites — Australia Post Retail Outlets, Licensed Post Offices and Community Postal Agents account for 4,400-plus outlets across the network). Small area, public-facing, Privacy Act 1988 acoustic separation requirement.
• Worker amenity and canteen (3–8 percent). 24/7 shift staffing means staggered occupancy.
• Vehicle wash bay (small). Wet zone with washdown extract.
• Generator and UPS backup (1–2 percent). N+1 diesel generators sized for the full HVAC load plus IT plus emergency lighting. UPS room for the data centre and the safety-critical systems.
• Solar inverter room and BESS room (1–3 percent). Rooftop solar PV inverters dissipate 2–5 percent of throughput as heat. BESS room AS/NZS 5139 plus NFPA 855 controls.

Each of these zones has its own outdoor-air calculation, conditioning strategy, and duct distribution method. Lumping them under one AHU and one main supply trunk produces a system that under-serves the high-occupancy zones, over-conditions the low-occupancy zones, and fails the code-compliance overlays on the security-controlled and hazardous-zone areas.

The cross-belt sorter heat extract — the single biggest design difference from a conventional warehouse

If there is one feature that distinguishes a modern parcel sortation centre from a conventional distribution warehouse, from an HVAC engineering standpoint, it is the cross-belt sorter loop. A major Australian Australia Post or DHL-class hub has a cross-belt sorter loop of 150–300 metres of continuous circulation, throughput of 12,000–30,000 parcels per hour, dissipating 80–250 kW of motor, belt friction, induction-station scanner heat and discharge-chute mechanical heat across the loop. The loop runs 16 hours a day on a typical operating profile, with peak intensity in the 02:00 to 06:00 inbound trunk-delivery window and again in the 18:00 to 22:00 next-day-despatch window.

The dominant Australian sortation centre approach to handling this heat load is a dedicated sorter-loop AHU separate from the general bulk-floor AHU. The reasoning is:

• Load profile mismatch. The general bulk-floor AHU has a peak load profile dominated by solar gain through the roof — peaking 12:00 to 16:00 on a summer day, falling overnight to a fraction of the peak. The sorter-loop AHU has a near-flat 16-hour load profile dominated by the equipment heat — almost constant from 06:00 to 22:00. Trying to size one AHU to both load profiles produces a unit that is either oversized for the steady sorter load or undersized for the summer peak.
• Heat rejection geometry. The sorter heat plume rises buoyantly to the apex of the sorter hall. Capturing it requires extract grilles directly above the loop, not distributed across the building. The dedicated AHU runs supply at induction and discharge (worker positions) and extract at the apex, in a stratified-displacement configuration.
• Energy efficiency. Conditioning only the lower 4–6 metres of the air column at the workforce positions, allowing the stratified hot layer to vent at the apex, cuts cooling load 30–40 percent versus full-volume conditioning. The dedicated AHU loop locks this efficiency in.
• Maintenance independence. The sorter operates 16 hours a day, year-round, and any AHU service that affects sorter operation costs the operator throughput. The dedicated AHU allows planned maintenance to be scheduled in the 22:00 to 02:00 quiet window without affecting the general bulk floor.

The duct package for a major sorter loop is:

• Supply main — galvanised spiral 1,400–1,800 mm diameter on the SBKJ SBTF-2020 spiral tubeformer, feeding dropped supply terminals at induction and discharge stations 4–6 metres above the floor with adjustable jet diffusers.
• Extract main — galvanised spiral 1,600–2,000 mm diameter on the SBKJ SBTF-2020, running along the underside of the apex above the sorter footprint with capture grilles every 8–12 metres along the loop. The extract main discharges to a roof-mounted fan rated for continuous 16-hour duty.
• Plenum and AHU connection — rectangular galvanised duct on the SBKJ SBAL-V auto duct line in 0.8–1.5 mm gauge with TDF flange forming and integrated stiffener bead rolling.
• Sound attenuator — rectangular stainless plenum with longitudinal seam welds on the SBKJ SB-ZF1500 stitchwelder. Sound attenuation is important at the dedicated AHU because the sorter operates 16 hours a day and the workforce is positioned underneath the supply diffusers — a noisy supply main becomes a daily noise-exposure issue.

Air mail security HVAC — the four-tier cascade at the gateway centres

At the Australia Post Loop Sortation Centres in Sydney, Melbourne and Brisbane, the courier express hubs at the major airport mail facilities, and any international gateway facility processing air mail, the air mail zone is subject to ICAO Annex 17 security controls and the Australian federal Aviation Transport Security Act 2004 Air Cargo Security Program. The HVAC implications are not subtle.

The standard zoning is four tiers, each with its own pressure relationship and duct boundary:

• Tier 1 — Known consignor receiving. Inbound air freight from regulated air cargo agents and known consignors. Negative pressure relative to the secure holding tier downstream, to prevent contaminant migration from receiving to secure holding. Modest outdoor air rate (typical bulk sortation rate plus 50 percent uplift for the higher occupant turnover at the receiving counter).
• Tier 2 — X-ray screening. Lead-shielded x-ray cabinets screen consignments for explosive and dangerous goods. The room is neutral pressure relative to receiving but slightly negative to the secure holding tier downstream. The x-ray cabinet exhaust is HEPA-filtered (H13 minimum) to capture sputtered tungsten and lead particulate from the x-ray tube anodes. Duct penetrations through the lead-shielded wall use 1.5–2.0 mm lead sheet bonded to galvanised duct in the penetration sleeve, with continuous lead-to-lead overlap to maintain the radiation shielding.
• Tier 3 — Secure holding. Cleared consignments awaiting tarmac despatch. Positive pressure relative to the screening tier upstream, to prevent any unscreened contaminant from migrating back into the cleared zone. Continuous CCTV, biometric access, tamper-evident sealing on every duct penetration.
• Tier 4 — Tarmac despatch. Loading onto the unit-load device (ULD) for cargo aircraft uplift. Slightly positive pressure relative to the airside environment. Cross-references the SBKJ Airport and Aviation HVAC Duct Guide for the airside detail.

The duct system implements this cascade with security dampers at every penetration across a security boundary, tamper-evident sealing (tamper-evident bolts and security wire on every flange), and continuous duct integrity monitoring through the BMS. The lead-shielded x-ray room duct package uses 304 stainless on the cabinet exhaust extract (corrosive vapour from any cargo leak that passes through the cabinet) on the SBKJ SBAL-V with stainless tooling, with longitudinal seam welds on the SBKJ SB-ZF1500 stitchwelder.

Dangerous goods consignment cell — AS/NZS 60079, sub-compartmentation, and 304 stainless

The dangerous goods consignment cell is the segregated holding area where parcels declared as DG (the nine UN DG classes) are stored pending despatch. Class 1 explosives, Class 2 gases (including refrigerated and high-pressure), Class 3 flammable liquids, Class 4 flammable solids, Class 5 oxidising agents, Class 6 toxic and infectious substances, Class 7 radioactive material, Class 8 corrosive substances, and Class 9 miscellaneous dangerous goods.

The HVAC implications cascade from AS/NZS 60079 hazardous area classification, AS 1940 flammable liquid storage, AS 4214 gaseous suppression and the operator's own DG handling procedure under ICAO Annex 18 (for DG routed to air freight) and the Australian Dangerous Goods Code (for DG routed to road freight). The working design is:

• Hazardous-zone classification. The cell is classified Zone 2 under AS/NZS 60079 with a continuous-pilot ventilation system that holds the atmosphere below 25 percent of the lower explosive limit of any credible release. All electrical equipment inside the cell is explosion-protected. The duct material is 304 stainless (corrosive vapour from Class 8 acid and alkali leaks) and the duct construction is spark-resistant — non-ferrous tooling on the SBKJ forming line, no ferrous mechanical contact in the duct interior, and a spark-resistant fan (typically aluminium impeller in a non-ferrous casing) at the discharge.
• Continuous mechanical ventilation. 10–15 air changes per hour, sized for the highest credible release scenario across all classes stored in the cell. Make-up air via a dedicated intake from a clean outdoor location.
• Negative pressure. The cell is held at minus 25 to minus 50 Pa relative to the surrounding sortation floor to prevent any contaminant migration into the general workforce area.
• Single-pass extract. The extract air is discharged direct to atmosphere via a dedicated spiral riser routed away from any air intake. No recirculation, no shared return path with the general building HVAC.
• Sub-compartmentation by DG class. Incompatible classes get separate ventilation circuits with separate extract risers. Class 1 explosives and Class 5 oxidising agents in particular must not share extract paths, because a mixed ignition risk is materially higher than any single-class risk.
• AS 4214 gaseous suppression. The cell is sprinklered only with care (Class 3 flammable liquid storage is generally not sprinklered because water spreads burning fuel) and primarily protected by AS 4214 gaseous suppression — typically Novec 1230 or FM-200 with full discharge interlocked with the ventilation system shutdown to maintain the suppression concentration during the design hold time.
• Spark-resistant duct construction. SBKJ spark-resistant configurations of the SBAL-V auto duct line and SBTF-2020 spiral tubeformer use non-ferrous tooling on the forming line and 304 stainless or aluminium duct material to eliminate any spark ignition risk inside the duct system. The SBKJ Box Hill North VIC engineering team has shipped spark-resistant configurations into multiple Australian DG cell projects.

Hazmat decontamination cell — the Anthrax-era contingency that remains live

In the months after the 2001 Anthrax-letter incidents in the United States, every major postal operator in the developed world built a hazmat decontamination cell into their sortation centre design. The Australian operators retained the requirement and re-pressed it into service for fentanyl-laced-mail screening and biological-agent containment through the 2010s and 2020s. The cell is small (8–20 m²) but high-spec.

The standard configuration is:

• Negative pressure single-pass HEPA extract. The cell is held at minus 25 to minus 75 Pa relative to the surrounding sortation floor. Extract air passes through HEPA H14 filtration and discharges to atmosphere via a dedicated stack 3+ metres clear of any air intake. No recirculation.
• High air change rate. 20+ ACH, sized to clear the cell to operator re-entry condition within 60 seconds of a screening event.
• Double-door airlock entry. The cell is accessed via a vestibule with interlocked doors to maintain the negative pressure containment.
• Bag-in bag-out HEPA housings. The HEPA filters are changed without operator exposure via a bag-in bag-out housing. This is a critical safety feature — the contamination is on the upstream face of the HEPA and a conventional filter change would expose the maintenance worker.
• 304 stainless duct material. The duct interior is decontaminated periodically with a chlorine-based or peroxide-based wipe-down. Galvanised duct would corrode at the seams under repeated chemical decontamination, so 304 stainless is the standard specification. SBKJ SBAL-V with stainless tooling produces this duct on the auto duct line.

EV delivery van charging and BESS room — the new HVAC requirement for last-mile depots

Through 2024 to 2026 the Australian parcel and e-commerce operators committed to large-scale electric delivery van fleet rollouts. Australia Post is rolling out 1,000-plus EVs across its metropolitan fleet by 2030 (with the depot-charging infrastructure built ahead of the fleet). Coles online has committed to a similar fleet replacement on a 10-year horizon. Woolworths X, the major couriers (DHL, FedEx, TOLL, Aramex), and the e-commerce operators (Amazon, THE ICONIC, Catch) are all on parallel commitments. From an HVAC engineering standpoint, this introduces a new requirement that distribution warehouse design has not historically had to cover.

The EV delivery van charging zone is typically built as a covered or partially enclosed bay at the back of the despatch dock, with 20–80 charging positions on AC Level 2 chargers (7–22 kW per position) and occasional DC fast chargers (50–150 kW). The HVAC design has to handle three risks:

• Lithium-ion battery thermal runaway risk. Any large lithium-ion installation requires AS/NZS 5139 and NFPA 855 controls — smoke detection per AS 1670, gas detection (HF, CO and combustible vapour from electrolyte off-gassing), gaseous suppression per AS 4214, and mechanical extract sized for 4–6 ACH minimum at the active charging zone with the capability to ramp to 12–15 ACH on a battery-fault detection signal. The detection signal interlocks the suppression discharge with the ventilation ramp to maintain inerting concentration through the suppression hold time.
• Residual diesel and petrol fume from the legacy fleet. Through the 5–10 year transition period, the EV fleet operates alongside the legacy ICE fleet in the same depot. The legacy fleet emits diesel particulate matter (target EC 0.1 mg/m³), CO (30 ppm TWA, never exceed 100), NO2 (5 ppm STEL) and unburnt fuel vapour at the despatch dock. Design 8–12 ACH at the active despatch zone to clear the legacy emissions, with the cleared air discharged to atmosphere via the despatch-dock extract stack.
• Warm air rejection from DC fast-charging power electronics. DC fast chargers dissipate 5–15 percent of charging power as waste heat. A 150 kW DC fast charger rejects 7.5–22.5 kW of heat into the bay. Distributed across 4–8 DC fast positions, this is 30–180 kW of continuous heat rejection at the active charging zone. The HVAC has to extract this load without dropping the bay below ambient, which is a balance design point — partial conditioning of the bay at 22–26°C with the warm air drawn off at the apex and discharged via the despatch-dock extract.

The BESS room — the grid-connected battery storage that backs up the rooftop solar PV at most modern parcel sortation centres — runs on a separate HVAC system with the full AS/NZS 5139 plus NFPA 855 controls: smoke and gas detection, AS 4214 gaseous suppression, mechanical extract at 4–6 ACH minimum, ramp capability to 12–15 ACH on fault signal, and spark-resistant duct construction on the extract path. The duct material is 304 stainless or aluminium (corrosive vapour from electrolyte off-gassing) on the SBKJ SBAL-V with stainless tooling and the SBKJ SBTF spiral tubeformer in spark-resistant configuration.

Cold-chain parcel handling — chilled at 2–8°C, frozen at minus 18 to minus 22°C

The growth segment within parcel logistics is cold-chain handling — meal kits (HelloFresh, Marley Spoon, Dinnerly), grocery e-commerce (Coles online, Woolworths X, IGA online, Bakers Delight bake-at-home), medical and pharmaceutical (Australia Post Sameday, the major hospital pharmacy networks), and frozen specialty (Aussie Fresh, the major seafood and ice-cream distributors). The HVAC implications are substantial.

The standard cold-chain parcel handling facility runs three temperature bands inside the same building shell:

• Ambient handover zone. Where the ICE or EV last-mile van interfaces with the cold-chain handling floor. Ambient HVAC with dock-seal vestibules and air-curtain interlocks at the dock doors to minimise air leakage between the ambient and chilled zones.
• Chilled handling at 2–8°C. The dominant cold-chain band for meal kits, medication, dairy, fresh produce. Dedicated refrigeration plant with insulated panel construction, vapor-tight envelope, dock-seal vestibules. Duct material is 304 stainless throughout — galvanised duct fails on condensation-driven white rust at the seams within 8–15 years, and the unplanned maintenance cost over a 25–30 year facility life is materially higher than the up-front stainless premium. SBKJ SBAL-V configured with stainless tooling produces the rectangular 304 stainless duct in 0.8–1.5 mm gauge.
• Frozen handling at minus 18 to minus 22°C. Frozen meals, seafood, ice cream. Same duct material specification (304 stainless) with insulated double-skin spiral on the supply mains. SBKJ SBTF spiral tubeformer configured for stainless coil produces the round duct.

The single most failure-prone detail in cold-chain parcel handling is the vapor barrier integrity at the boundary between ambient and chilled (and between chilled and frozen). Specify continuous vapor-tight envelope on the cold side, sealed insulated duct sleeves at all penetrations, dedicated air handling on each side with no shared returns, and dock-seal vestibules at fork-truck and conveyor doors. Cross-reference the SBKJ Cold Storage & Cold Chain HVAC Duct Guide for the full vapor-barrier, dock-seal and refrigeration-plant detail.

Sound attenuator and plenum construction in stainless is on the SBKJ SB-ZF1500 stitchwelder — the longitudinal seam welds on stainless plenum are produced by the stitchwelder at production rates that hand TIG welding cannot match. Stainless seam-fold work for fittings and transitions is on the SBKJ SBSF-1525.

Forklift charging room — hydrogen, lithium-ion and LPG

Forklift charging in an Australian parcel sortation centre or e-commerce fulfilment centre is in the middle of a technology transition. The legacy lead-acid fleet is being replaced by lithium-ion at most major operators, with some operators (Coles, Woolworths, the major 3PLs) trialling hydrogen fuel-cell forklifts. Each technology has its own HVAC implication.

• Lead-acid forklift charging. Hydrogen evolution during the gassing phase. AS/NZS 60079 Zone 2 classification with mechanical ventilation sized to keep hydrogen below 1 percent of the lower explosive limit. Typical design is 6 ACH minimum continuous ventilation with elevated rate during the active gassing phase. SBKJ spark-resistant SBTF spiral configuration on the extract.
• Lithium-ion forklift charging. No hydrogen evolution in normal operation, but thermal runaway risk at fault condition. AS/NZS 5139 and NFPA 855 plus AS 1670 detection and AS 4214 gaseous suppression. Mechanical extract at 4–6 ACH minimum with ramp to 12–15 ACH on fault signal. Spark-resistant duct construction.
• Hydrogen fuel-cell forklift refuelling. AS/NZS 60079 Zone 2 classification on the dispensing area with dedicated hydrogen leak detection interlocked with the ventilation system. The dispensing nozzle and storage cylinders are above ground in a well-ventilated bay with no enclosed roof structure that would allow hydrogen accumulation. SBKJ spark-resistant duct fabrication uses non-ferrous tooling and aluminium or 304 stainless duct material.
• LPG forklift refuelling. AS 5601 LPG handling controls with CH4 1.25 percent LEL detection. The refuelling area is segregated from the indoor sortation floor with an external open-air refuelling point being the dominant Australian approach. Indoor LPG operation is permitted with elevated ventilation and CH4 detection, but the operational complexity drives most operators to indoor electric or hydrogen with LPG only for outdoor yard movements.

X-ray screening, customs and Border Force inspection — the international gateway overlay

At the international gateway parcel facilities (the Australia Post Loop Sortation Centres in Melbourne, Sydney and Brisbane, the courier express hubs at the major airport mail facilities, and any Australian Border Force-controlled facility processing international inbound mail), three additional zones overlay the base sortation HVAC.

• X-ray screening room. Lead-shielded cabinets screen consignments for explosive, dangerous goods and prohibited content. The room is dedicated extract with HEPA H13 filtration on the cabinet exhaust to capture sputtered tungsten and lead particulate from the x-ray tube anodes. Duct penetrations through the lead-shielded wall use 1.5–2.0 mm lead sheet bonded to galvanised duct in the penetration sleeve. Positive pressure to the operator booth, negative pressure to the inspection chamber. The room runs 16 hours a day at major gateways, so the HVAC is sized for continuous duty.
• Customs and Border Force inspection. Where Australian Border Force officers conduct physical inspection of declared and selected international inbound parcels. Clean and secure controlled environment with positive pressure to the surrounding sortation floor. Modest 50–200 m² area at major gateway sortation centres.
• Bonded warehousing. Where international inbound parcels are held pending Australian Border Force release. Secure controlled environment with continuous CCTV, biometric access and modest HVAC. Cross-references the SBKJ Container Port, Cargo Terminal, Stevedore and Ferry HVAC Duct Guide for the broader bonded-warehouse detail.

Last-mile depot HVAC — the smaller cousin to the major hub

The major sortation hub is the centrepiece of the parcel network, but the workhorse is the last-mile depot — the regional and suburban distribution depot from which the actual delivery vans dispatch. Australia Post operates several hundred of these. The courier operators (DHL, FedEx, UPS, TOLL, Aramex, Couriers Please, StarTrack) operate parallel networks. The grocery e-commerce operators (Coles online, Woolworths X) operate dark-store-fronted last-mile depots at city-fringe locations.

The typical last-mile depot is 3,000–15,000 m² floor plate, single-storey, with a roller-door despatch dock array along one side, a small manual sort floor in the centre, a driver crib and rest area, an EV and ICE van parking and charging zone, and a small admin office. The HVAC is significantly less complex than a major sortation hub — no automated cross-belt sorter, no air mail security zoning, no major DG handling — but the EV charging zone, the diesel particulate matter at the despatch dock, the 24/7 driver crib room and the cold-chain parcel handling (where applicable) all carry over from the major hub.

The standard duct package for a last-mile depot is:

• General floor supply — galvanised rectangular on the SBKJ SBAL-V auto duct line with TDF flange forming, 0.6–1.0 mm gauge, supplying the manual sort floor and the depot office at 22°C through dropped terminals.
• Despatch dock extract — galvanised spiral 800–1,200 mm diameter on the SBKJ SBTF spiral tubeformer at the dock face, capturing diesel particulate matter and routing to a roof-mounted extract fan.
• EV charging zone extract — spark-resistant 304 stainless or aluminium spiral on the SBKJ SBTF in spark-resistant configuration, 600–1,000 mm diameter, with the AS/NZS 5139 plus NFPA 855 detection and suppression interlock.
• Driver crib and rest area — galvanised rectangular on the SBKJ SBAL-V, 0.5–0.8 mm gauge, full conditioning at 22°C with the AS 1668.2 staggered-occupancy outdoor air calculation for the 24/7 shift profile.
• Cold-chain parcel handling (where applicable, at the grocery and meal-kit last-mile depots) — 304 stainless rectangular on the SBKJ SBAL-V with stainless tooling, with the chilled and frozen refrigeration plant and vapor-tight envelope.

Manual sortation, mail bag and letter holding — the legacy zones

Letter sortation, mail bag handling and overflow are the legacy zones in a modern parcel facility — the Australia Post 25 Letter Centres are still significant but the letter volume has been in long-term decline since the early 2000s as e-commerce parcel volume has grown. Manual sortation and pre-sort area are the legacy parcel zones at smaller centres without full automation, and remain significant at regional sortation centres where the throughput does not justify a cross-belt sorter loop.

The HVAC is straightforward — ambient ventilation with modest supplementary outdoor air at the manual sort workstations (10 L/s/person under AS 1668.2). No special equipment heat load. No security overlay (letter mail is not subject to air cargo security in the way parcel mail is). The duct package is galvanised rectangular on the SBKJ SBAL-V at 0.5–0.8 mm gauge with TDF flange forming, supplying the floor through standard ceiling diffusers.

Operator-specific notes — Australia Post, StarTrack, TOLL, DHL, FedEx, UPS, Aramex, Sendle, the e-commerce operators and the 3PLs

Different operators have different sub-zones, different operational profiles, different security and compliance overlays, and different procurement standards. The HVAC duct system has to flex to suit. Here are the operator-specific notes our engineers carry into every parcel-sector design review:

Australia Post (Australian Postal Corporation)

The federal government corporation that operates the largest parcel and letter network in the country — 4,400-plus retail outlets, 25 Letter Centres, 200-plus parcel centres, all major airport mail facilities. The operator with the longest history and the broadest infrastructure footprint. The 2050 net-zero commitment drives rooftop solar PV plus BESS at every new build. The AusPost service standard drives N+1 redundancy on every sortation-hall AHU. The Loop Sortation Centres in Melbourne, Sydney and Brisbane handle the international air mail and require the four-tier security HVAC cascade.

StarTrack (Australia Post Group)

The express parcel arm of Australia Post Group, with a separate operational identity but shared network infrastructure. Sortation centres are typically integrated with the Australia Post sortation centres or co-located at airport mail facilities. Same N+1 redundancy and net-zero commitment as the parent.

TOLL Group (Japan Post-owned)

TOLL Express, TOLL IPEC, TOLL Express Parcels and the broader TOLL Holdings logistics business. Japanese-owned through Japan Post since 2015. Operates a parallel parcel and freight network across Australia with strong concentration in NSW and Victoria. HVAC procurement standards lean toward the Japanese precision specification — tight tolerance on duct leakage class, high-grade galvanised coil specification.

DHL Express Australia (Deutsche Post DHL)

The German global express courier operator with major Australian gateway hubs at Sydney, Melbourne, Brisbane and Perth airport mail facilities. HVAC procurement standards follow the Deutsche Post DHL global engineering specification, which leans toward ASHRAE 62.1 and 90.1 cross-reference alongside the AS 1668.2 baseline. DHL has been an early mover on EV delivery van fleet and on rooftop solar PV.

FedEx Express Australia (Memphis US)

The US-headquartered global express operator. Australian gateway hubs at the major airport mail facilities. HVAC procurement follows the FedEx global engineering specification with ASHRAE references as the primary code stack and AS 1668.2 as the secondary local compliance overlay.

UPS Australia (United Parcel Service)

Similar profile to FedEx — US-headquartered, Australian gateway hubs at the major airport mail facilities, ASHRAE-first HVAC procurement with AS 1668.2 as the local compliance overlay.

Aramex Global Express (formerly Fastway)

Rebranded from Fastway in 2024–2025 following the Aramex global acquisition. Australian network of regional sortation centres and metropolitan last-mile depots. HVAC procurement is mid-range — neither the high-end DHL specification nor the cost-driven smaller-operator specification.

TNT (FedEx-acquired) and Couriers Please (Singapore Post)

TNT is the legacy Australian operation under FedEx ownership since 2016. Couriers Please is owned by Singapore Post. Both operate parallel sortation and last-mile networks.

Sendle (Sydney)

Australian SME parcel operator with a carbon-neutral commitment. Sendle does not operate its own sortation centres — it uses the Australia Post and Couriers Please networks under aggregator agreements — but the carbon-neutral commitment has driven Sendle to influence the HVAC specifications of its network partners toward NABERS-rated builds and rooftop solar PV.

Australia Post Sameday and Hubbed, Pickup Pak, Yoo Australia, DPD Australia

The smaller and specialty parcel operators. Australia Post Sameday operates the medical and pharmaceutical cold-chain parcel handling. Hubbed and Pickup Pak operate the parcel pickup network. Yoo Australia is Singapore-owned. DPD Australia is the former joint venture.

Linfox (Lindsay Fox)

The biggest Australian 3PL. Operates dedicated fulfilment centres for major retail and grocery clients. HVAC procurement is mid-to-high range with NABERS-rated builds standard on new developments. Strong concentration in Victoria and NSW with national coverage.

Toll Holdings (Japan Post), Mainfreight (NZ-listed), BlueArrow Logistics, Bonafide Australia, Visual Logistics, Mantel Group

The broader 3PL landscape. Mainfreight is the NZ-listed operator with a strong Australian presence. BlueArrow is the mid-range 3PL. Bonafide Australia and Visual Logistics serve the e-commerce 3PL segment. Mantel Group is the logistics technology layer.

Woolworths X (Woolworths Group, ASX:WOW)

The e-commerce arm of Woolworths Group, automated by Witron Logistik with autostore goods-to-person robotics. The Woolworths X fulfilment centres are hyperscale (40,000–80,000 m² floor plate) with the full automated fulfilment stack — autostore, conveyor sortation, putwall, autobagger. HVAC procurement standards are high — NABERS for Industrial 5-star benchmark with rooftop solar PV plus BESS, ASHRAE cross-reference, full N+1 redundancy. Cold-chain integration with the Woolworths supply-chain refrigeration plant.

Coles online (Coles Group, ASX:COL)

The e-commerce arm of Coles Group, on Ocado technology partnership since 2019. The Ocado MHE (material handling equipment) layer drives a very tight HVAC specification on the conditioned-air-quality requirement at the picking face — 18–22°C, 45–60 percent RH, ISO 14644 Class 9 or cleaner air quality. Dedicated AHUs feed the Ocado picking aisles via dropped spiral mains with slot diffusers at picking elevation.

Amazon Australia

Hyperscale fulfilment centres at Sydney, Melbourne, Brisbane and Perth. HVAC procurement follows the Amazon global engineering specification with ASHRAE references and AS 1668.2 as the local compliance overlay. Amazon Robotics goods-to-person workstations carry elevated outdoor air rates (15–25 L/s/person) because of the high pick-station occupant density. Amazon has been an aggressive early mover on rooftop solar PV and on EV delivery van rollout.

eBay Australia, THE ICONIC, Catch.com.au, Kogan, Officeworks, JB Hi-Fi, Bunnings Online, IKEA Australia, Temple & Webster, Adore Beauty, Cettire, Booktopia

The broader Australian e-commerce operator landscape. THE ICONIC operates Berlin-style fashion fulfilment centres in Sydney and Melbourne. Catch is owned by Wesfarmers. Kogan operates dedicated and 3PL fulfilment. Officeworks (Wesfarmers) and JB Hi-Fi handle bulky goods. Bunnings Online (Wesfarmers) handles the home-improvement parcel mix. IKEA handles flat-pack furniture which drives larger conveyor and larger sortation footprint. Temple & Webster handles homewares. Adore Beauty handles cosmetics. Cettire handles luxury fashion. Booktopia handles books and media. Each operator has its own sub-zoning but the underlying HVAC duct package is variations on the same theme.

HelloFresh, Marley Spoon, Dinnerly — the meal-kit operators

The meal-kit segment is German-headquartered (HelloFresh) and Sydney-headquartered (Marley Spoon and Dinnerly). All three operate Sydney, Melbourne and Brisbane fulfilment centres with chilled handling at 2–8°C and frozen handling at minus 18 to minus 22°C. HVAC procurement is cold-chain-specific with full 304 stainless duct on the cold zones and the vapor-tight envelope detail discussed under cold-chain parcel handling above.

Qantas Freight, Virgin Australia Cargo, Toll Aviation, Cathay Pacific Cargo, Singapore Airlines Cargo, ANA Cargo, JAL Cargo, EVA Air Cargo, Korean Air Cargo, DHL Aviation, FedEx Express Aviation

The air freight operators that interface with the parcel sortation centres at the airport mail facilities. Cross-references the SBKJ Airport and Aviation HVAC Duct Guide for the airside detail.

Industry bodies and the regulatory environment

The industry bodies and the regulatory environment for the Australian parcel and e-commerce fulfilment sector are:

• Australian Logistics Council (ALC). The peak industry body for the broader logistics sector, including parcel and freight. Publishes industry standards and policy positions.
• AAGA Australasian Air Freight Council. The peak body for air freight, including air mail and air cargo. Coordinates with ICAO Annex 17 and 18 compliance.
• TWU Transport Workers' Union. The dominant union covering the parcel and delivery workforce. Influences the 24/7 shift roster and the driver crib room amenity requirements.
• Postal Industry Ombudsman. Federal independent complaints body for postal services.
• Australia Post Group. The federal government corporation that operates the Australia Post and StarTrack networks.
• The major REIT industrial property landlords. Goodman Group, Charter Hall, ESR Australia, Logos, Centuria — each publishes industrial design standards that the parcel and fulfilment operators build to as tenants.

Duct material selection — galvanised, stainless and spark-resistant

The duct material selection across the typical Australian parcel and e-commerce fulfilment duct package is:

• Galvanised steel G90 (Z275 in EN), 0.5–1.5 mm gauge. The workhorse material across 60–70 percent of the duct package — general supply, return and exhaust mains across the bulk sortation floor, despatch dock, parcel acceptance, manual sort, mail bag handling, letter holding, office, amenity, public retail counter, conveyor maintenance shop, vehicle wash bay. Produced on the SBKJ SBAL-V auto duct line in rectangular with TDF flange forming, integrated stiffener bead rolling, Pittsburgh seam closure, and on the SBKJ SBTF-2020 spiral tubeformer in round.
• 304 stainless steel, 0.8–1.5 mm gauge. The dominant material across the cold-chain handling zones (chilled at 2–8°C and frozen at minus 18 to minus 22°C), the dangerous goods consignment cell (corrosive vapour from Class 8 acid and alkali leaks), the hazmat decontamination cell (repeated chemical decontamination), the x-ray cabinet exhaust on the air mail screening line, and the BESS room extract on the lithium-ion electrolyte off-gassing. SBKJ SBAL-V configured with stainless tooling produces the rectangular; SBKJ SBTF configured for stainless coil produces the round; SBKJ SB-ZF1500 stitchwelder produces the longitudinal seam welds on stainless plenum and sound attenuator construction; SBKJ SBSF-1525 produces the stainless seam-fold work on fittings.
• 316L stainless steel, 0.8–1.5 mm gauge. Specified where chloride exposure is elevated — typically the cold-chain parcel handling zone at coastal sortation centres where the prevailing wind carries salt aerosol, and the dangerous goods cell where Class 8 chloride-bearing acid is held. SBKJ SBAL-V with 316L stainless tooling produces this duct.
• Aluminium, 1.0–1.5 mm gauge. Specified for the spark-resistant duct at hydrogen fuel-cell forklift refuelling and at lithium-ion BESS room extract. Lighter than stainless, lower spark ignition risk, more easily fabricated with non-ferrous tooling. SBKJ spark-resistant SBTF spiral tubeformer configuration produces aluminium spiral.
• Lead-sheet-lined galvanised, 1.5–2.0 mm lead bonded to galvanised carrier. Specified only at the x-ray cabinet penetration through the lead-shielded wall, with continuous lead-to-lead overlap to maintain radiation shielding.
• Pre-insulated double-skin spiral, 0.8–1.5 mm gauge with continuous polyurethane foam insulation between inner and outer skin. Specified on conditioned supply mains running through unconditioned roof voids, on the sorter-loop AHU supply main, and on the cold-chain supply mains. Reduces thermal loss in non-conditioned voids and contributes to NABERS for Industrial fan-energy efficiency. SBKJ pre-insulated double-skin SBTF spiral configuration produces this.

Smoke management — AS 1668.1 plus AS 4391 across the bulk sortation hall

The smoke management overlay applies to the bulk sortation hall plus AS 4391 for warehouses over 18,000 m² (most modern Australian parcel sortation centres qualify) plus AS 1668.1 across the office, amenity and public retail counter. The working approach is:

• Powered smoke exhaust at the roof apex sized to maintain a smoke-free layer above the highest sprinkler head, integrated with sprinkler activation under AS 2118 and detection under AS 1670. Typical major sortation centre has 15–25 powered roof exhaust fans rated 5,000–15,000 L/s each. Smoke-rated spiral exhaust risers on the SBKJ SBTF-2020 in heavy-gauge galvanised (1.0–1.5 mm gauge) with EI 60 or EI 120 fire-rated wrapping per AS 1530.4.
• Make-up air via roller-door interlocks. The roller doors at the despatch dock and the inbound truck dock open automatically on smoke detection to provide make-up air for the powered smoke exhaust. The interlock is coordinated with the BMS fire-mode logic.
• Smoke compartmentation across the sortation hall. Smoke curtains at the boundary between the bulk sortation hall and the air mail security zone, between the bulk sortation hall and the dangerous goods cell, and between the bulk sortation hall and the cold-chain handling zone. The compartmentation drives the maximum smoke spill flow rate and the largest single duct flow rate in the building.
• AS 1851 maintenance regime. Annual fire damper test, fan run test, sprinkler discharge test, detection system test. The HVAC duct system has to remain accessible for this maintenance through the operational life of the facility.

NABERS for Industrial and the Australia Post 2050 net-zero commitment

NABERS for Industrial has expanded over the period 2020–2026 to cover logistics warehouses, refrigerated DCs, AS/RS sites and parcel sortation centres. It is now a standard tender requirement from Goodman Group, Charter Hall, ESR Australia, Logos and Centuria. The Australia Post 2050 net-zero commitment, the Linfox and Toll equivalents, the Coles and Woolworths emissions commitments, and the multinational operator (Amazon, DHL, FedEx, UPS) global net-zero commitments all amplify the same requirement.

The HVAC duct system optimisations that move the NABERS rating are:

• Spiral mains at 8–10 m/s for low pressure loss and low fan energy. Fan energy at 1.2–1.8 W per L/s is the NABERS-competitive band. SBKJ SBTF-2020 spiral tubeformer produces the long mainlines.
• AS/NZS 4254 Class C leakage minimum (under 4 percent leakage at design pressure). Properly produced SBKJ spiral on the SBTF-2020 routinely tests at Class C. Properly produced SBKJ rectangular on the SBAL-V with TDF flange forming and proper sealant application tests at Class B-C.
• Pre-insulated double-skin spiral on conditioned mains through unconditioned roof voids. Reduces thermal loss in non-conditioned voids. SBKJ pre-insulated double-skin SBTF spiral configuration produces this.
• Full ductwork commissioning records. Leakage test certificates per AS 4254, air balance reports per AABC or NEBB, smoke control commissioning report per AS 1668.1.
• Solar PV roof integration with HVAC load matching. The HVAC plant runs on the solar generation profile during the day, drawing from the grid only at peak summer load and overnight. Grid-connected BESS sized for 4–8 hours of operational HVAC load is increasingly common.
• Heat recovery on the outdoor-air pathway. Thermal wheel or plate exchanger on the AHU outdoor-air pathway recovers 60–75 percent of the temperature difference between outdoor and return air. Cuts heating energy in winter and cooling energy in summer.
• Demand-controlled ventilation. CO2 sensors at the manual sort workstation cluster, occupancy sensors at the driver crib room, and the BMS modulates outdoor air rate to meet the AS 1668.2 minimum under actual occupancy rather than design occupancy. Saves 15–30 percent of fan energy across the shoulder seasons.

Worked example — duct package for a 50,000 m² Australia Post automated sortation centre

To make the numbers concrete, here is a worked example for a 50,000 m² Australia Post-class automated sortation centre in Melbourne or Sydney with a 200-metre cross-belt sorter loop, an air mail security zone, a dangerous goods cell, an EV delivery van charging zone, a rooftop solar PV plus BESS installation, and a small cold-chain parcel handling zone.

Step 1 — Confirm building scale and zoning

50,000 m² total floor plate. 30,000 m² bulk sortation including the cross-belt sorter loop. 5,000 m² air mail security zone (four-tier). 1,000 m² dangerous goods cell. 1,500 m² cold-chain parcel handling (chilled at 2–8°C). 3,000 m² last-mile despatch dock with EV charging. 2,500 m² conveyor, plant and BESS room. 4,000 m² office, amenity, driver crib, public retail counter and admin. 3,000 m² circulation, vehicle wash, generator, plant access.

Step 2 — Calculate total outdoor air demand

Bulk sortation at 0.5 L/s/m² over 30,000 m² = 15,000 L/s. Air mail security at variable rates per tier averaging 0.6 L/s/m² over 5,000 m² = 3,000 L/s. Dangerous goods cell at 12 ACH continuous = 4,000 L/s. Cold-chain handling at 0.4 L/s/m² over 1,500 m² = 600 L/s. Despatch dock at 10 ACH = 12,000 L/s (averaged over the 16-hour active window). Conveyor and plant at 0.3 L/s/m² = 750 L/s. Office and amenity at 10 L/s/person at 200 design occupants = 2,000 L/s. Sub-totals plus engineering allowance for the diversity factor and the manual sort station outdoor-air uplift = approximately 45,000–55,000 L/s total building outdoor air demand. Approximately 50,000 L/s working number.

Step 3 — Locate and size AHUs

One dedicated cross-belt sorter loop AHU at 30,000 L/s (sized for the 200 kW continuous heat load plus the sortation-zone supply). Four general bulk-floor AHUs at 20,000 L/s each = 80,000 L/s general supply with N+1 redundancy. One dedicated air mail security AHU at 12,000 L/s with the four-tier pressure cascade. One dedicated dangerous goods cell exhaust at 4,000 L/s spark-resistant. One dedicated cold-chain refrigeration package. One dedicated despatch dock extract at 15,000 L/s for the diesel and EV charging zone. One office and amenity rooftop packaged AHU at 8,000 L/s. Total installed AHU capacity approximately 150,000 L/s with N+1 redundancy on the critical units.

Step 4 — Size main supply trunks

Each 20,000 L/s bulk-floor AHU at 10 m/s velocity supplies a 1,596 mm diameter main trunk — round up to 1,600 mm spiral. Four bulk-floor mains at 1,600 mm spiral. Sorter-loop AHU at 30,000 L/s at 10 m/s supplies a 1,954 mm diameter main — round up to 2,000 mm spiral. Air mail security AHU at 12,000 L/s at 9 m/s supplies a 1,303 mm main — round up to 1,400 mm spiral. Dangerous goods cell exhaust at 4,000 L/s at 8 m/s supplies a 798 mm spark-resistant 304 stainless main — round up to 800 mm spiral. Despatch dock extract at 15,000 L/s at 10 m/s supplies a 1,382 mm main — round up to 1,400 mm spiral. Office and amenity at 8,000 L/s at 8 m/s supplies a 1,128 mm main, but the office distribution is rectangular, so this lands as a 1,200 mm × 800 mm main on the SBKJ SBAL-V auto duct line.

Step 5 — Branch and terminal distribution

Branch trunks step down through 1,200 mm, 1,000 mm, 700 mm and 500 mm diameters across the floor plate. Dropped supply terminals 4–6 m above floor at 300–500 mm diameter with adjustable jet diffusers across the bulk sortation. Sorter-loop dropped terminals at induction and discharge stations at 400–600 mm diameter. Air mail security tier supplies at 250–400 mm diameter with security dampers at every penetration. Dangerous goods cell extract grilles at 400–600 mm diameter sub-compartmented by DG class. Cold-chain supply at 300–500 mm diameter in 304 stainless. Despatch dock low-level extract grilles at 500–800 mm. Office linear slot diffusers at 250–400 mm diameter spirals plus 300 mm × 100 mm rectangular branch.

Step 6 — Add smoke exhaust mains

20 powered roof exhaust fans at 10,000 L/s each, with 1,600–2,000 mm spiral risers from the apex down to the fan platform. Total smoke-exhaust spiral footage approximately 200–400 m, plus exhaust trunks across the smoke reservoir compartments and the EI 60 or EI 120 fire-rated wrapping per AS 1530.4.

Step 7 — Add BESS, solar inverter and backup generator HVAC

BESS room at 4 ACH minimum on a 200 m² room = 1,200 L/s extract. Solar inverter room at 8 ACH on a 50 m² room = 400 L/s. Backup generator room at the engine combustion-air-plus-cooling demand = typically 3,000–6,000 L/s. Total BESS plus inverter plus generator HVAC = 5,000–8,000 L/s on dedicated extract and supply.

Step 8 — Calculate total annual duct production

For a duct contractor producing this scale of project once a year alongside conventional warehouse and supermarket DC work, annual output is approximately 80,000–140,000 m² of duct surface area. The SBKJ SBTF-2020 spiral tubeformer at 25–40 m/min runs single-shift for approximately 900–1,400 hours per year producing the spiral. The SBKJ SBAL-V auto duct line runs single-shift for approximately 700–1,200 hours per year producing the rectangular. The SBKJ SB-ZF1500 stitchwelder runs 200–400 hours per year producing the stainless plenum and sound attenuator longitudinal seam welds. The SBKJ SBSF-1525 runs 100–250 hours per year on the stainless seam-fold work. The SBKJ SBFB-1500 spiral fitting former produces the spiral fittings and transitions at 150–300 hours per year. The SBKJ SBPC1500 plasma table runs 100–250 hours on access plates, dampers and inspection covers. The SBKJ SBLR-600 longitudinal seam welder runs 80–200 hours on heavy-gauge plenum and AHU plenum construction. All lines have spare capacity for adjacent industrial-segment projects.

The SBKJ machine package — what produces this duct

The SBKJ machine package that produces the duct mix described above is engineered from our Box Hill North VIC office in Melbourne, with the engineering team and the field service support based in Australia. The machines themselves are world-class, with the engineering, sizing, commissioning and after-sales support delivered locally:

SBAL-V auto duct line — the workhorse for rectangular galvanised and stainless

The SBKJ SBAL-V auto duct line handles G90 galvanised coil and 304 / 316L stainless coil from 0.5 to 1.5 mm thickness, producing rectangular duct up to 1,500 mm wide with TDF flange forming, integrated stiffener bead rolling, and Pittsburgh seam closure. Output rates 8–12 metres per minute on standard configurations. This is the workhorse line for general parcel hub and sortation duct (galvanised) and for cold-chain parcel handling, dangerous goods cell and hazmat decontamination duct (stainless). Stainless-capable tooling is rapid-changeover so a single line can swap between galvanised and stainless production within a shift without cross-contamination of the stainless surface with carbon-steel residue.

SBTF-2020 spiral tubeformer — long mainlines and sorter-loop extract

The SBKJ SBTF-2020 spiral tubeformer produces round spiral duct from 100 mm up to 2,000 mm diameter in galvanised, 304 stainless and pre-insulated double-skin formats. Output rates 25–40 metres per minute. This is the workhorse for the long mainlines (bulk-floor supply, sorter-loop supply and extract, smoke exhaust risers), the cold-chain supply mains (304 stainless), and the spark-resistant duct for forklift charging and dangerous goods cell (304 stainless in spark-resistant configuration with non-ferrous tooling). For diameters above 2,000 mm, the contractor either jumps to the larger SBKJ machine or constructs the trunk as multiple parallel 2,000 mm spirals at the AHU outlet.

SB-ZF1500 stitchwelder — stainless plenum and sound attenuator

The SBKJ SB-ZF1500 stitchwelder produces longitudinal seam welds on stainless plenum and sound attenuator construction at production rates that hand TIG welding cannot match. This is critical for the cold-chain plenum (sound attenuation on the supply to chilled and frozen handling), the sorter-loop AHU sound attenuator (16-hour continuous operation underneath the supply diffusers), and the dangerous goods cell extract plenum.

SBSF-1525 — stainless seam-fold work

The SBKJ SBSF-1525 produces stainless seam-fold work on fittings, transitions and small-diameter cold-chain ducting. Pairs with the SBAL-V for the rectangular straight runs and the SB-ZF1500 for the plenum and attenuator longitudinal seams.

SBFB-1500 — spiral fitting former

The SBKJ SBFB-1500 spiral fitting former produces the elbows, branch tees, reducers and transitions that connect the SBTF-2020 spiral mains to the dropped terminals and the branch trunks. The fittings are produced at the same diameter range (up to 1,500 mm) and the same material specification (galvanised, 304 stainless) as the mainline spirals.

SBPC1500 plasma table — access plates, dampers, inspection covers

The SBKJ SBPC1500 plasma table cuts access plates, fire dampers, motorised volume control dampers, smoke dampers, inspection covers and the duct shapes that the forming lines cannot directly produce. CNC controlled, cuts galvanised and stainless coil up to 6 mm thickness.

SBLR-600 longitudinal seam welder — heavy-gauge plenum

The SBKJ SBLR-600 longitudinal seam welder produces longitudinal seam welds on heavy-gauge plenum and AHU plenum construction where stitch-welding is not adequate to the static pressure or the structural load. Common on the sorter-loop AHU plenum, the air-mail security AHU plenum, and the smoke-exhaust-fan inlet plenum.

Spark-resistant configurations

The SBKJ SBTF-2020 spiral tubeformer and the SBKJ SBAL-V auto duct line are available in spark-resistant configurations with non-ferrous tooling on the forming line and 304 stainless or aluminium duct material. These are specified for the forklift charging room, the hydrogen fuel-cell forklift dispensing area, the LPG forklift refuelling zone (under AS 5601), the dangerous goods consignment cell (under AS/NZS 60079) and the BESS room extract on the lithium-ion electrolyte off-gassing.

Procurement timeline — from concept to commissioning on a 50,000 m² Australian parcel sortation centre

The typical procurement timeline our engineers carry into early-engagement discussions is:

• Months 1–4 (concept and schematic design). Site selection, REIT engagement, zoning, code stack confirmation, climate envelope, AHU sizing concept, smoke management strategy, NABERS for Industrial target, solar PV plus BESS sizing.
• Months 4–8 (developed design and tender documentation). Detailed zoning, duct sizing on each zone, AHU specification, smoke management calculation under AS 1668.1 and AS 4391, hazardous-zone classification under AS/NZS 60079, BESS room AS/NZS 5139 plus NFPA 855, security HVAC under ICAO Annex 17 and the Aviation Transport Security Act 2004, cold-chain refrigeration plant sizing, EV charging zone integration, tender documentation issued to HVAC duct contractors.
• Months 8–12 (procurement and shop drawings). HVAC duct subcontract awarded, shop drawings issued, coil specifications locked, SBKJ machine sizing and quotation finalised, SBKJ engineering team confirms the machine combination to the contractor's coil specification.
• Months 12–18 (fabrication and delivery). Duct fabrication ramps up on the contractor's SBKJ lines, mainlines delivered first (smoke-exhaust risers and AHU connections), then branch and terminal distribution, then office and amenity duct.
• Months 18–22 (installation). Mainlines installed first with crane lifts through the roof, then branch and terminal distribution, then office and amenity, then commissioning prep.
• Months 22–24 (commissioning). AS 4254 leakage testing, AABC or NEBB air balance, AS 1668.1 smoke control commissioning with hot smoke testing in the critical compartments, NABERS for Industrial commissioning records, handover documentation.
• Months 24–36 (first-year tuning). Seasonal commissioning return at peak summer and peak winter to retune economiser changeover, demand-controlled ventilation setpoints, smoke control fire-mode interlocks, BESS detection and suppression interlock, dangerous goods cell ventilation under actual operating contaminant load.

Field service and aftermarket support — Box Hill North VIC engineering

The SBKJ field service and aftermarket support is delivered from our Box Hill North VIC engineering office in Melbourne, with field service engineers based in Australia. The typical aftermarket support package across the parcel and e-commerce fulfilment segment is:

• Machine commissioning on site at the duct contractor's facility — typically 5–10 days on the SBAL-V, 3–7 days on the SBTF-2020, 2–4 days on each of the SB-ZF1500, SBSF-1525, SBFB-1500, SBPC1500 and SBLR-600.
• Operator training — typically a 5-day training course on the SBAL-V and SBTF-2020, with the contractor's lead operators trained to a level where they can handle routine setup, changeover and minor adjustment without SBKJ field service support.
• Spare parts inventory — held in Melbourne at our Box Hill North VIC office for next-business-day despatch to the major industrial centres (Truganina, Eastern Creek, Larapinta, Forrestfield).
• Annual preventive maintenance return visit — typically 2–4 days on each line annually to verify alignment, replace consumable wear parts, recalibrate the control system and update the firmware if required.
• Engineering support for new coil specifications — when the contractor needs to add a new gauge, a new material (typically when adding stainless to a previously galvanised-only line) or a new duct configuration to the production mix, SBKJ engineering supports the tooling change and the production setup.
• Project-specific engineering support — for unusual configurations (spark-resistant, lead-shielded, pre-insulated double-skin, ultra-high pressure class) SBKJ engineering supports the specification and the fabrication test pieces ahead of the production run.

FAQ

What outdoor air rate does AS 1668.2 require for an Australia Post automated sortation centre?

AS 1668.2 classifies the bulk parcel handling floor as low-occupancy storage and processing with elevated mechanical contaminant load from conveyor motor heat and tyre dust. Typical outdoor air design is 0.4–0.6 L/s/m² on the bulk floor, supplemented by 10 L/s/person at induction stations and manual sort islands, plus elevated rates at the inbound truck dock (10–15 ACH for diesel particulate matter). Air mail security and dangerous goods zones add ICAO Annex 17, Aviation Transport Security Act 2004 and AS/NZS 60079 overlays that override the base AS 1668.2 calculation.

How do you size HVAC extract for a cross-belt sorter or tilt-tray sorter heat load?

A modern automated cross-belt sorter (Bastian Solutions, Dematic, SSI Schaefer, Vanderlande, TGW) with 12,000–24,000 parcels per hour dissipates 80–250 kW of motor and friction heat across the loop. Capture this with a localised supply-and-extract — supply at 20–24°C above induction and discharge stations, extract at the apex above the sorter loop at 6–10 ACH over the sorter footprint. Most modern Australian sortation facilities run a dedicated sorter-loop AHU separate from the general bulk-floor AHU.

What ventilation does a forklift charging room require under AS/NZS 60079?

Lead-acid charging evolves hydrogen and requires AS/NZS 60079 Zone 2 mechanical ventilation at 6 ACH minimum to hold hydrogen below 1 percent of the lower explosive limit. Lithium-ion requires AS/NZS 5139 plus NFPA 855 plus AS 4214 gaseous suppression. Hydrogen fuel-cell refuelling requires AS/NZS 60079 Zone 2 with dedicated H2 leak detection. LPG forklift requires AS 5601 with CH4 1.25 percent LEL detection. SBKJ spark-resistant duct construction with 304 stainless or aluminium on non-ferrous tooling eliminates ignition risk.

How is a dangerous goods consignment cell ventilated?

AS/NZS 60079 hazardous-zone enclosure with continuous 10–15 ACH spark-resistant extract direct to atmosphere via dedicated spiral riser, negative pressure relative to the surrounding sortation floor, sub-compartmentation by DG class (incompatible classes get separate ventilation circuits), 304 stainless duct material for corrosive vapour from Class 8 leaks, spark-resistant fan construction, AS 4214 gaseous suppression with ventilation interlock.

Do last-mile depots with EV delivery van charging need special HVAC?

Yes. AS/NZS 5139 and NFPA 855 controls on the lithium-ion charging zone, AS 1670 detection, AS 4214 gaseous suppression on the BESS room, 4–6 ACH minimum extract with ramp to 12–15 ACH on fault signal, plus 8–12 ACH on the despatch dock for residual diesel particulate matter from the legacy ICE fleet, plus partial conditioning of the bay to handle the 5–15 percent of charging power dissipated as DC fast-charger waste heat. SBKJ spark-resistant duct on the active charging zone.

What pressure relationship does an air mail security zone require?

ICAO Annex 17 and the Aviation Transport Security Act 2004 drive a four-tier cascade: known consignor receiving (negative), x-ray screening (neutral), secure holding (positive), tarmac despatch (slightly positive). Security dampers at every penetration across a security boundary, tamper-evident sealing, lead-shielded duct walls 1.5–2.0 mm at the x-ray cabinet penetration, HEPA H13 filtration on the cabinet exhaust.

What duct material does cold-chain parcel handling need?

304 stainless on the chilled (2–8°C) and frozen (minus 18 to minus 22°C) zones, replacing galvanised at 10–15 year life on condensation-driven white rust at galvanised seams. SBKJ SBAL-V configured with stainless tooling produces 0.8–1.5 mm 304 stainless rectangular; SBKJ SBTF spiral tubeformer configured for stainless coil produces the round; SBKJ SB-ZF1500 stitchwelder produces longitudinal seam welds on plenum and sound attenuator.

What is the typical SBKJ machine package for an Australian parcel sortation duct contractor?

One SBKJ SBAL-V auto duct line for rectangular galvanised and stainless mains (TDF flange, stiffener bead, Pittsburgh seam), one SBKJ SBTF-2020 spiral tubeformer for round mainlines up to 2,000 mm (galvanised, stainless, pre-insulated double-skin), one SBKJ SB-ZF1500 stitchwelder for stainless plenum and sound attenuator longitudinal seams, one SBKJ SBSF-1525 for stainless seam-fold work, one SBKJ SBFB-1500 spiral fitting former, one SBKJ SBPC1500 plasma table for access plates and dampers, one SBKJ SBLR-600 longitudinal seam welder for heavy-gauge plenum, plus spark-resistant configurations of the SBTF-2020 and SBAL-V for hazardous-zone duct.

How does NABERS for Industrial change duct selection on a new parcel sortation centre?

Spiral round duct has lower friction loss than rectangular at equivalent cross-sectional area and tests at AS/NZS 4254 Class C leakage — both contribute to lower fan energy and a higher NABERS star rating. Pre-insulated double-skin spiral on conditioned mains through unconditioned roof voids reduces thermal loss. Solar PV roof integration with HVAC load matching, demand-controlled ventilation, and heat recovery on the outdoor-air pathway all feed into the rating. The Australia Post 2050 net-zero commitment, the Linfox and Toll equivalents, and the major REIT requirements all amplify the same direction.