The minimum temperature at work in the UK is normally 16°C, or 13°C where much of the work involves rigorous physical effort. These figures come from HSE’s Approved Code of Practice. The law itself says indoor temperatures must be “reasonable” and sets no maximum. Where the figures cannot be reached, employers should provide local heating, protective clothing, rest facilities and breaks.
Every winter the same question comes up in offices, warehouses and workshops: how cold does it have to get before something must be done? This guide sets out the minimum temperature at work under the Workplace (Health, Safety and Welfare) Regulations 1992 and HSE’s guidance, what counts as too cold or too hot, and the practical steps employers are expected to take.
What is the minimum temperature at work in the UK?
The minimum is normally 16°C for indoor workplaces, or 13°C where much of the work involves rigorous physical effort. These figures come from HSE’s Approved Code of Practice L24, which explains how to meet regulation 7 of the Workplace Regulations.
| Type of work | Minimum temperature | Typical examples |
|---|---|---|
| Mainly sedentary or light work | At least 16°C | Offices, call centres, reception areas, control rooms |
| Work involving rigorous physical effort | At least 13°C | Warehouse picking, manual handling, some manufacturing and maintenance work |
| Where these figures are impractical | As close to the figures as practical | Cold stores, food chilling areas, loading bays open to the outside |
Source: HSE L24, Workplace health, safety and welfare: Approved Code of Practice, paragraphs 61 and 62.
HSE points out that these figures will not necessarily provide reasonable comfort. A room at 16°C can still feel cold if there is a draught, if people sit still all day, or if the floor is cold underfoot.
What the law actually says
Regulation 7 of the Workplace (Health, Safety and Welfare) Regulations 1992 requires that during working hours the temperature in all workplaces inside buildings “shall be reasonable”. The regulation itself does not give a number.
Regulation 7 also requires that:
- workplaces are insulated where necessary, having regard to the type of work and the physical activity involved;
- excessive heating from sunlight is avoided;
- heating or cooling methods do not give off fumes, gas or vapour likely to injure or offend anyone;
- enough thermometers are provided for people to check the temperature in any indoor workplace.
The 16°C and 13°C figures sit in the Approved Code of Practice. An ACOP is not law in itself, but it has a special legal status. If an employer is prosecuted and did not follow the ACOP, they would need to show they complied with the law in some other way that was just as good. In practice, treat 16°C and 13°C as the floor unless the work makes them impractical.
Behind regulation 7 sits the general duty under the Health and Safety at Work Act 1974 and the requirement to assess risks under the Management of Health and Safety at Work Regulations 1999. Temperature is a workplace hazard like any other.
Is it illegal to work below 16°C?
Not automatically. A temperature below 16°C in a sedentary workplace means the employer is falling short of the ACOP guideline and should act, but the legal test is whether the temperature is reasonable and whether reasonable steps have been taken.
L24 recognises that some workplaces cannot be kept at 16°C, such as rooms open to the outside or areas where food has to be kept cold. There, the employer should get as close to the guideline as is practical and use other controls to protect workers. Ignoring a cold workplace with no heating, no breaks and no warm areas is a different matter.
Where should workplace temperature be measured?
Take readings close to workstations, at working height and away from windows. L24 also says thermometers should be available at suitable points throughout the workplace, though not necessarily in every room, and should not be placed in front of windows or next to heat sources.
A thermometer on a corridor wall next to a radiator tells you little about the desk by the draughty window. If staff complain, measure where they actually work.
Is there a maximum temperature at work?
No. HSE states there is no law for a maximum working temperature. High temperatures often come from the work itself, for example in bakeries, foundries and kitchens, so a single upper limit would not work across every industry.
That does not remove the duty. The temperature must still be reasonable, and heat is assessed like any other risk. L24 lists steps for excessive heat, including insulating hot plant and pipes, providing air cooling, shading windows and siting workstations away from radiant heat.
What should employers do when it is too cold?
Start with heating the space, then reduce exposure, then protect the person. HSE’s guidance on managing workplace temperature and L24 point to these measures:
- Provide adequate heating so work areas are warm enough when occupied, including temporary heating for normally unoccupied rooms such as storerooms if people work there for more than a short time.
- Use local heating where the whole room cannot be kept comfortable, for example heaters near fixed workstations.
- Cut draughts while keeping ventilation adequate. Self-closing doors help in chilled areas.
- Insulate cold floors or provide suitable footwear for people who stand for long periods.
- Limit exposure through job rotation and by designing processes to reduce time in cold areas.
- Allow breaks so people can get hot drinks and warm up in a heated area.
- Provide suitable protective clothing where cold cannot be avoided.
Rest areas and toilets also need a reasonable temperature, and changing and shower rooms should not be cold.
What should employers do in a heatwave?
HSE’s practical list for hot workplaces includes:
- fans, air cooling or air conditioning, with adequate ventilation and windows that can be opened;
- blinds or reflective film to shade workers from direct sun, and moving workstations away from windows and heat sources;
- cold drinking water, with enough breaks for people to drink and cool down;
- relaxing formal dress codes, while making sure required PPE is still worn;
- flexible working patterns and job rotation, and scheduling heavy or PPE-heavy work for cooler parts of the day.
Outdoor workers
The 16°C and 13°C figures apply to indoor workplaces. Outdoor work in cold or hot weather is still covered by the duty to assess and control risks. HSE’s outdoor working guidance suggests:
| Cold weather | Hot weather |
|---|---|
| Suitable PPE and warm clothing | Reschedule work to cooler parts of the day |
| Mobile warming facilities, with soup or hot drinks | More frequent breaks in shaded rest areas |
| More frequent rest breaks | Free access to cool drinking water |
| Postpone work to warmer months where safe to do so | Shade where people are working, and let workers remove PPE during breaks |
| Train workers to spot early signs of cold stress | Train workers to spot early signs of heat stress |
Source: HSE, Outdoor working.
The Workplace Regulations do not apply to construction sites. For duties on site, see our guide to the CDM Regulations 2015.
Thermal comfort: why the thermometer is only part of it
HSE describes thermal comfort as depending on six factors, which is why two people in the same room can disagree about whether it is cold.
| Factor | What it means in practice |
|---|---|
| Air temperature | What the thermometer reads. Useful, but not enough on its own |
| Radiant temperature | Heat from the sun, ovens, machinery, or the chill from cold windows and walls |
| Air movement | A small draught can feel uncomfortable in cool conditions |
| Humidity | High humidity slows sweat evaporation and makes heat harder to bear |
| Clothing and PPE | Too little leaves people cold; non-breathable PPE can cause heat stress even in mild conditions |
| Work rate | Physical work generates body heat, which is why the minimum drops to 13°C for rigorous effort |
Source: HSE, Thermal comfort.
HSE suggests asking workers or their safety representatives whether they are satisfied with the thermal environment, using its workplace temperature checklist, and reassessing at different times of year if conditions change with the seasons. Your risk assessment is the place to record what you found and what you are doing about it.
Workers who need extra consideration
Some people are more affected by heat and cold. HSE suggests health surveillance or medical screening for workers who are pregnant, have illnesses or disabilities, or take certain medication. Once a worker tells you in writing that she is pregnant, you must carry out an individual risk assessment and make any changes needed.
If anyone reports temperature-related illness, review the situation and put controls in place.
Frequently asked questions
What is the minimum temperature for working in an office?
The HSE Approved Code of Practice says the temperature should normally be at least 16°C for sedentary work such as offices. The legal requirement under regulation 7 of the Workplace Regulations 1992 is that the temperature is reasonable.
Is it illegal to work below 16°C?
Not automatically. 16°C is the guideline in HSE’s Approved Code of Practice, not a figure written into the regulations. Below it, the employer should take steps to warm the workplace or protect workers, such as local heating, warm clothing and breaks. Where 16°C is impractical, such as in cold stores, the aim is to get as close as practical.
What is the minimum temperature for physical work?
Where much of the work involves rigorous physical effort, the HSE Approved Code of Practice sets the minimum at normally at least 13°C.
Is there a maximum temperature at work in the UK?
No. HSE states there is no law for a maximum working temperature, because high temperatures often come from the work itself, for example in bakeries or foundries. Employers must still keep the temperature reasonable and manage heat as a risk.
Where should the temperature be measured?
Close to workstations, at working height and away from windows. Thermometers should not be placed in front of windows or near heat sources.
Does the minimum temperature apply to outdoor workers?
No. The 16°C and 13°C figures apply to indoor workplaces. Outdoor workers are protected by the duty to assess and control risks, which includes warm clothing, warming facilities, hot drinks and more frequent breaks in cold weather.
What should an employer do if the workplace is too cold?
Provide adequate heating, use local heaters where the whole room cannot be warmed, reduce draughts, insulate cold floors, allow breaks for hot drinks in a warm area, rotate jobs to limit exposure, and provide suitable protective clothing where cold cannot be avoided.
Where to learn more
- Office Safety Training: Workplace Regulations duties for offices, including temperature and welfare
- Health and Safety Awareness: a one-day course for all employees on workplace hazards, risk control and reporting
- Risk assessments: a UK guide
- Display screen equipment regulations explained
- Preventing slips, trips and falls
Talk to KeyOstas
Temperature complaints are often the first sign that other workplace welfare duties need a look. Our Office Safety and Health and Safety Awareness courses are delivered at your site for up to 12 delegates.
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