Heat Stress Management SWMS
Heat stress risk management for outdoor construction, mining, agriculture, and industrial workers — WBGT monitoring, work-rest scheduling, acclimatisation, hydration, and emergency response.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Heat stress is a recognised physical hazard under the model Work Health and Safety Act 2011 and corresponding WHS Regulations adopted across most Australian jurisdictions. Workers in outdoor construction, mining, agriculture, civil works, roofing, road maintenance, and indoor hot-process industries (foundries, bakeries, laundries, glassworks) face elevated risk of heat-related illness ranging from heat rash and cramps through to heat exhaustion and life-threatening heat stroke. Section 19 of the WHS Act imposes a primary duty on the Person Conducting a Business or Undertaking (PCBU) to ensure, so far as reasonably practicable, that workers are not exposed to thermal environments that pose a risk to health and safety.
This Safe Work Method Statement (SWMS) addresses the systematic identification, assessment and control of heat stress hazards in accordance with the Safe Work Australia Managing the Risks to Workers in Heat Code of Practice, ISO 7933 (Predicted Heat Strain) for analytical assessment, and Wet Bulb Globe Temperature (WBGT) monitoring as referenced in ACGIH TLV methodology. It integrates acclimatisation protocols, work-rest cycles, hydration management, personal risk factor screening, and emergency cooling response — including AS 1338-aligned cold-water immersion treatment for severe heat stroke.
While heat stress work is not categorised as High Risk Construction Work under WHS Regulation 291, a documented SWMS is strongly recommended (and in many principal contractor contracts, mandated) wherever environmental conditions, workload, or PPE create foreseeable heat illness risk. Failure to manage heat stress has resulted in successful prosecutions, Coronial findings of preventable deaths, and significant Category 1 and 2 offences under sections 31–33 of the WHS Act.
Hazards identified
12 hazards covered, sorted by priority.
Core body temperature >40°C, multi-organ failure, death within hours if untreated
Collapse, dizziness, vomiting, hospitalisation; precursor to heat stroke
Impaired decision-making, reduced reaction times, secondary incidents (falls, plant strikes)
5x higher heat illness risk in first 5 days; majority of fatal cases involve unacclimatised workers
Effective WBGT increased by 3–6°C; rapid core temperature rise
Skin burns, accelerated heat gain, elevated globe temperature readings
Painful muscle spasms, work cessation, masking of more serious heat illness
Cardiac event, syncope, individual susceptibility unmanaged
Impaired thermoregulation, increased dehydration, masked symptoms
No effective cool-down period; cumulative heat strain across shift
Acute burns reducing thermoregulation; melanoma and non-melanoma skin cancers
Delayed emergency response, progression from exhaustion to stroke, fatality
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Conduct daily WBGT monitoring using a calibrated heat stress meter (e.g. Kestrel 5400) at the work location, recording readings at 0900, 1200 and 1500 and triggering work-rest schedules per ACGIH TLV tables based on metabolic workload classification (light/moderate/heavy/very heavy)
- 2Implement a documented 7–14 day acclimatisation programme for new starters, returning workers (>7 days absence) and seasonal transfers — commencing at 20% workload day 1, increasing 20% daily, with direct supervisor sign-off each day
- 3Provide cool potable water within 50 metres of all work areas at a target intake of 250mL every 15–20 minutes; supplement with electrolyte replacement (low-sugar oral rehydration) for shifts exceeding 2 hours of moderate-heavy work
- 4Establish shaded, ventilated rest areas with a target temperature ≥6°C below ambient, fitted with seating, water, and where practicable mechanical cooling or evaporative misting
- 5Reschedule heavy physical tasks to early morning or evening when forecast WBGT exceeds 30°C; cease all non-essential work above WBGT 32°C unless engineering controls (cooling vests, air-conditioned cabins) are deployed
- 6Issue and train workers on Phase Change Material (PCM) cooling vests, wide-brim hats, UPF50+ long-sleeve shirts, and SPF50+ broad-spectrum sunscreen reapplied every 2 hours per Cancer Council Australia guidance
- 7Conduct pre-start toolbox talks covering daily forecast, WBGT trigger levels, symptom recognition (the 'mate-check' buddy system), location of cool zones, and emergency cooling procedure
- 8Screen workers via fitness-for-work questionnaire identifying medications, medical conditions, prior heat illness history, sleep, alcohol use and hydration status — escalate at-risk individuals to supervisor for task reallocation
- 9Maintain an emergency response capability including: ice slurry or ice-water immersion tub on site (per AS 1338 / Bouchama protocol), shaded triage area, first aider trained in heat stroke recognition, and direct comms to 000 with site GPS coordinates pre-loaded
- 10Apply mandatory rest-water-shade cycles based on WBGT: e.g. heavy work at WBGT 28–30°C requires 25 minutes work / 35 minutes rest per hour; document compliance in shift log
- 11Implement lone/remote worker check-in protocol — minimum 2-hourly radio or app-based welfare checks (e.g. SafetyIQ, StaySafe) with automated escalation if missed
- 12Where ISO 7933 Predicted Heat Strain analysis indicates exposure exceeds limits, engineer the task (mechanisation, remote operation, climate-controlled cabins) before relying on administrative controls per the hierarchy in WHS Regulation 36
Applicable Codes of Practice
Primary regulator-endorsed guidance defining duty-holder obligations for thermal environment risk assessment, controls and emergency response
Mandates elimination/substitution/engineering controls before administrative measures and PPE for heat risk
Requires documented training on heat illness recognition, hydration, acclimatisation and emergency response
Provides quantitative assessment method for predicting maximum allowable exposure time and required water intake
Eye protection specification for workers exposed to radiant heat sources in hot-process environments
Specification for breathable, UV-protective workwear suitable for hot environments
International benchmark WBGT screening criteria referenced by Safe Work Australia for work-rest scheduling
Who this is for
- →Principal contractors and construction PCBUs managing outdoor crews during summer (Nov–Mar) or in tropical/arid regions year-round
- →Mining and resources operators (open-cut, surface infrastructure, exploration drilling) particularly in WA Pilbara, NT and Qld coalfields
- →Agricultural and horticultural employers including harvest contractors, shearing teams, and irrigation/fencing crews
- →Civil and roadworks contractors performing asphalt laying, line marking, and traffic management on hot pavements
- →Industrial PCBUs operating foundries, bakeries, commercial laundries, glassworks, smelters and powder-coating facilities
- →Emergency services and utility crews (linesmen, water authority field staff) responding in extreme heat conditions
- →Site safety advisors, HSEQ managers and CIH/OHS consultants developing thermal stress management plans
What you receive
- ✓Fully editable Microsoft Word (DOCX) SWMS template with branded cover page and project-specific fields
- ✓State-specific WHS legislation schedule covering NSW, VIC, QLD, WA, SA, TAS, ACT and NT variants
- ✓Comprehensive heat stress hazard register with 12 pre-populated risk entries and residual risk scoring matrix
- ✓Worker sign-on register with acknowledgement of acclimatisation status and medical declaration
- ✓WBGT monitoring log template with ACGIH work-rest trigger thresholds
- ✓Acclimatisation programme tracker for new, returning and transferred workers
- ✓Heat illness emergency response flowchart including AS 1338-aligned cold-water immersion procedure
- ✓Pre-start toolbox talk script and daily fitness-for-work questionnaire
- ✓Editable PDF version for field use and printing
Worked example
A civil contractor in Townsville is laying kerb and channel during late November. The site supervisor opens the Heat Stress Management SWMS at the morning pre-start. The 0700 WBGT reading is already 27°C with a Bureau of Meteorology forecast peak of 33°C and 78% humidity. Using the ACGIH TLV table embedded in the SWMS, the supervisor classifies concrete finishing as 'heavy work' and identifies that by 1100 the crew will require a 25/35 work-rest ratio. Two workers — one returning from a three-week leave, one a new labour-hire starter on day 2 — are flagged on the acclimatisation tracker and reassigned to lighter duties (formwork stripping in shade) at 60% workload. At 1340 a worker reports dizziness and stops sweating despite continued exertion — recognised by his buddy as a red-flag symptom of incipient heat stroke. The crew activates the SWMS emergency procedure: the worker is moved to the shaded triage tent, immersed to the neck in the on-site ice-water tub (pre-stocked per the SWMS equipment list), and 000 is called with GPS coordinates already saved in the site phone. Core temperature is reduced below 39°C within 12 minutes — well inside the 'cool first, transport second' window endorsed by the Australian Resuscitation Council. The incident is documented, ICAM-investigated, and the SWMS is reviewed and re-signed by all workers the following morning.
Related legislation
- Work Health and Safety Act 2011 (Cth model) – sections 19, 27, 28
- Work Health and Safety Regulation 2017 (NSW) / 2011 (Qld) / OHS Regulations 2017 (Vic)
- Safe Work Australia Model Code of Practice: Managing the Risks to Workers in Heat and Cold
- Safe Work Australia Model Code of Practice: First Aid in the Workplace
- Sun Protection and UV Radiation – Cancer Council Australia / ARPANSA guidance
- Fair Work Act 2009 – section 65 (right to refuse unsafe work) and modern award heat-related provisions
- Mining Work Health and Safety (Resources) Regulations – jurisdiction-specific (e.g. WA WHS (Mines) Regs 2022)
Frequently asked questions
Is a SWMS legally required for heat stress management in Australia?
Heat stress work is not listed as High Risk Construction Work under WHS Regulation 291, so a SWMS is not strictly mandated by that regulation. However, the PCBU's primary duty under section 19 of the WHS Act and the documented risk management requirements of WHS Regulations 32–38 effectively require a written, controlled procedure wherever heat illness is foreseeable. Most principal contractors and tier-1 clients contractually require a heat stress SWMS as part of site induction.
What WBGT level should trigger work cessation?
There is no single universal cut-off. The ACGIH TLV approach used in this SWMS sets screening thresholds based on workload and acclimatisation status — for example, unacclimatised workers performing heavy work should reduce activity at WBGT ≥25°C, and all work above WBGT 32°C with heavy exertion should cease unless engineering controls (cooling vests, air-conditioned cabins) are in place. The SWMS includes the full ACGIH table and decision tree.
How long does acclimatisation take and who needs it?
Full physiological acclimatisation typically takes 7–14 days of progressive heat exposure. It is required for new starters, workers returning from more than 7 days' absence (leave, illness, training), workers transferring from cooler climates, and at the start of the hot season. The SWMS provides a day-by-day workload progression schedule (20%, 40%, 60%, 80%, 100%) with supervisor sign-off.
What is the correct first aid for suspected heat stroke?
Heat stroke is a medical emergency with a >40% fatality rate if untreated. Current Australian Resuscitation Council and Safe Work Australia guidance is 'cool first, transport second' — immerse the casualty in cold/ice water up to the neck (per AS 1338-aligned protocol) while awaiting paramedics. Cooling within the first 30 minutes dramatically improves survival. The SWMS includes a step-by-step emergency response flowchart and equipment checklist.
Does this SWMS cover indoor hot-process work as well as outdoor?
Yes. The template includes scope sections and hazard controls applicable to foundries, bakeries, commercial laundries, glassworks and smelters as well as outdoor construction, mining and agriculture. Radiant heat, metabolic load from PPE, and ventilation/engineering controls are addressed for both environments.
Can I edit the SWMS for my specific site and workforce?
Absolutely. The document is supplied as a fully editable Microsoft Word (DOCX) file with no licence restrictions on internal use. You should customise the scope, site address, supervisor details, emergency contacts, WBGT trigger thresholds and crew sign-on for each project, and review at least annually or after any heat-related incident.