Quick answer
Assess hot, cold and severe-weather risks and put suitable controls in place. The indoor duty is to provide a reasonable temperature; normal 16°C or 13°C guidance is not an absolute limit for every process. There is no fixed statutory maximum workplace temperature, so decisions need to consider the work, environment and people.
A thermometer reading is only part of the decision
Humidity, heat from equipment, air movement, work rate and required clothing can change how conditions affect a worker. Outdoor weather can also change routes, machinery use and access to help.
HSE explains the GB temperature duties and HSENI explains the separate NI rules. Both distinguish a reasonable indoor temperature from the absence of a fixed legal maximum. Employers still need to assess and control the risks.
1. Understand what the normal indoor figures mean
| Statement | Practical meaning |
|---|---|
| Reasonable indoor temperature | The applicable legal duty depends on the work and conditions. |
| Normally at least 16°C | A normal indoor guideline in the relevant official guidance, rather than a complete assessment. |
| 13°C for rigorous physical effort | The normal lower figure relates to that type of work; it is not a target for every workplace. |
| No fixed statutory maximum | Heat remains a hazard requiring assessment and control. |
The GB workplace ACOP explains practical exceptions, including where food must be kept cold. HSENI makes a similar distinction for NI. Such processes still need suitable precautions for workers; food-storage needs do not remove the worker-safety assessment.
2. Change the environment and the way work is organised
HSE’s temperature-management guidance includes suitable cooling/heating, ventilation, reducing radiant heat or draughts, rest facilities and changes to exposure or workload.
| Condition | What to review |
|---|---|
| Hot indoor work | Heat sources, ventilation, local cooling, work rate and access to water and suitable breaks. |
| Cold rooms or processes | Reducing time exposed, suitable clothing, draughts, contact with cold surfaces and warming facilities. |
| Required PPE | Whether the protection and task can be improved without removing necessary safeguards. |
| Individual needs | Consultation, reported difficulties and any suitable occupational-health advice needed. |
Check that changes preserve necessary protection, ventilation and hygiene arrangements. In a kitchen, moving air or changing work patterns needs to fit the cooking and food-safety controls as well as comfort.
3. Make decisions for outdoor and severe-weather work
HSE’s outdoor guidance addresses suitable timing, shelter, breaks, water and protection in hot or cold conditions. Consider sun exposure as well as air temperature.
Use current Met Office warnings and local conditions as inputs to the workplace assessment. Decide who checks conditions, whether access routes and planned tasks remain suitable, what changes or delay are needed and how workers will receive the decision.
Hypothetical example: a hot kitchen and outdoor delivery area
A business reviews the heat around cooking equipment and the workload of staff unloading outside. It considers ventilation and heat sources indoors, delivery timing and shade outside, water, breaks and individual feedback. One air-temperature reading from the office would not assess those two jobs.
4. Review concerns before they become routine
Tell workers how to report uncomfortable or unsafe conditions. Reassess when weather, equipment, workload or reported illness indicates the arrangements are inadequate. Use the workplace’s appropriate care and emergency response where someone becomes unwell.
- A claimed universal maximum or automatic walkout number. Assess the actual risk and obtain appropriate advice.
- Cold-food work treated as exempt from protection. Assess and control exposure.
- Removing necessary PPE to cope with heat. Review the task and controls.
- Weather information without an owner or decision. Agree who changes the work and tells people.
Next steps
- Review the actual environment, work rate, clothing and people affected.
- Apply the relevant temperature guidance and duties.
- Agree environmental and work-organisation controls.
- Monitor weather and feedback, communicate changes and reassess.
Read HSE’s workplace-temperature guidance — Use the official distinction between duties, normal guidance and risk-based controls.