Heat Stress Toolbox Talk Template
Heat stress occurs when the body cannot keep its temperature under control. It depends on more than the air temperature: humidity, radiant heat, physical work rate, clothing and personal factors matter. A crew can be at risk indoors near a hot process or outdoors in hot weather. The employer must assess the risk where heat stress is possible and apply controls suited to the task. This talk helps workers recognise the plan and report early symptoms; it is not a substitute for the assessment, medical advice or an emergency procedure. HSE heat stress guidance.
A direct answer for the briefing lead
Copyable briefing card
| Field | Complete before the shift/task |
|---|---|
| Work area, date, briefing lead | [ ] |
| Task, expected work rate and duration | [ ] |
| Heat sources, weather, humidity and airflow | [ ] |
| PPE/protective clothing and effect on cooling | [ ] |
| Workers new to the task or environment; private health route | [ ] |
| Risk-assessment reference and current control plan | [ ] |
| Cooler time, shade, ventilation or process change | [ ] |
| Drinking water and rest-area access | [ ] |
| Acclimatisation and supervision arrangements | [ ] |
| Symptoms/stop-work trigger and first-aid contact | [ ] |
Opening script: “Today's task is [work] in [conditions]. We have planned [controls] because the job, clothing and environment can trap heat. If you feel dizzy, sick, unusually tired or unable to concentrate, stop and tell someone immediately. Look out for the same signs in a colleague. We will review the work if conditions change.”
Discuss prevention before symptoms appear
Reduce heat and work rate. Move work to a cooler period where possible, shield or ventilate hot processes, use mechanical aids and adjust the pace. These measures may be more effective than simply telling everyone to drink more. A worker in impermeable protective clothing may be unable to cool normally even when the measured air temperature seems modest. Never remove protective clothing that controls another serious hazard without an assessed alternative.
Provide practical recovery. Identify drinking water and an accessible cooler rest location. Agree who can call a break or reduce the task when conditions become difficult. New workers and those returning after an absence may need a suitable acclimatisation plan. Do not set a universal number of minutes in the sun from this template; HSE calls for risk assessment and, where needed, specialist advice. HSE heat stress guidance.
Recognise worsening illness. HSE lists poor concentration, cramps, rash, severe thirst, fainting and heat exhaustion symptoms such as fatigue, dizziness, nausea and headache. Confusion, collapse or convulsions are emergency signs. Stop the work, move the person to a safer cool place if it is safe to do so, get the trained first aider and call emergency services according to the site emergency plan. Do not assume all serious heat illness presents with dry skin, and do not leave a confused person to recover alone. The site first-aid plan governs immediate response.
Protect privacy. Some workers may be more susceptible because of medication, a health condition, pregnancy or lack of acclimatisation. The briefing should give a private way to raise concerns rather than ask people to disclose medical details to the whole crew. HSE advises that expert occupational-health input may be needed for difficult cases.
Questions for workers
- What has changed today: temperature, humidity, clothing, work rate or the duration of the task?
- Where is the water and the cooler rest area? Who can authorise a pause?
- Who is new to this environment or returning after a break, and how is their work being introduced safely?
- What symptom would make you stop work and get help for yourself or a colleague?
- Who is the trained first aider, and how would you call them from this work area?
If a control is unavailable, record the action and hold or modify the affected task. A signed talk cannot make a hot environment safe without the planned controls.
Attendance and action record
| Name/role | Understood controls and help route | Question/action | Acknowledgement |
|---|---|---|---|
| [ ] | [ ] | [ ] | [ ] |
Briefing outcome [controls in place / task changed / task held]; owner [ ]; follow-up [ ]; assessment version [ ].
Example: roof work in hot weather
A roofing team is working in direct sun while wearing required protective equipment. The schedule was written in cooler weather. The supervisor moves the most strenuous portion to an earlier period, confirms safe access to water and rest, and checks whether a new worker needs a gradual start. A worker reports dizziness, and the supervisor stops the work and follows the first-aid plan. The team does not dismiss the symptoms because there is no statutory “maximum UK working temperature”; HSE expects risks to be assessed and controlled. HSE workplace temperature overview.
Avoid these mistakes
- Using a single outdoor temperature as a universal safe/unsafe threshold.
- Treating drinking water as the only control for heavy work in PPE.
- Requiring workers to disclose private medical information in a group.
- Giving a talk while the agreed shade, rest or supervision arrangements are absent.
- Confusing heat stress with ordinary discomfort and delaying emergency help.
Source, ownership and writer-side QA
Primary source: HSE heat stress guidance, reviewed 6 October 2026; it supports the risk factors, controls, symptoms and need for assessment. No invented statutory upper temperature or universal break interval. Ownership: Live Complys toolbox hub did not list heat stress among its eight observed topics; targeted site search did not find an exact topic owner. Final repo search required. Internal link/product: The existing toolbox talk hub is a relevant parent after confirming its actual route and product claims. Do not claim Complys monitors temperature, determines fitness or provides medical advice. Disposition: READY writer-side, with site-specific assessment and final publication QA.