Is it too cold or hot to work?
Working in cold temperatures
The minimum temperature in an indoor workplace should normally be at least:
- 16°C or
- 13°C if much of the work involves rigorous physical effort
There are practical steps you can take to keep people as comfortable as possible when working in the cold.
The Workplace (Health, Safety and Welfare) Regulations require employers to provide a reasonable indoor temperature in the workplace.
This depends on the work activity and the environmental conditions.
The Construction (Design and Management) Regulations require reasonable workplace temperatures for indoor areas of construction sites.
Where the site is outdoors, you must provide protection from adverse weather. Site rest facilities must also be maintained at an appropriate temperature.
What is a reasonable working temperature?
As an employer, you must decide what a reasonable temperature should be in your workplace:
- assess the risk
- act on any findings by putting controls in place, including temporary or seasonal ones
- use our heat stress checklist (PDF) if workers are at risk from extreme temperatures
Working in hot temperatures
There’s no law for maximum working temperature, or when it’s too hot to work, because every workplace is different.
No meaningful upper limit can be imposed because in many indoor workplaces high temperatures are not seasonal but created by work activity, for example in bakeries or foundries.
However, employers must stick to health and safety at work law, including:
- keeping the temperature at a comfortable level
- providing clean and fresh air
How to protect workers
There are practical steps you can take to protect workers in high or low temperatures.
Workers should talk to their employer if the workplace temperature isn’t comfortable.
Find out about making workers feel more comfortable.
Outdoor working
Working outdoors in hot or cold environments for long periods of time can affect workers’ health. The HSE have guidance on how you can protect people from the risks of outdoor working.
If your job involves extreme temperatures
In some workplaces extreme temperatures can be created by the work activity, such as some manufacturing processes. These temperatures can lead to serious health effects if not managed effectively.
You can find advice if you are working in very high or low temperatures, for example on heat stress, dehydration or cold stress.
How you manage the effects of temperature depends on:
- whether the workplace is indoors or outdoors
- the normal operating temperature of that environment
Indoor workplaces
You should provide:
- a reasonable working temperature in workrooms – usually at least 16°C, or 13°C for strenuous work
- local heating or cooling (using fans, opening windows, using radiators) where a comfortable temperature cannot be maintained throughout each workroom, such as in hot and cold manufacturing processes
- rest facilities where necessary, eg for hot work or warm clothing in cold stores
- heating systems which do not give off dangerous or offensive levels of fume into the workplace
Outdoor workplaces
The HSE have separate advice for those working outdoors.
When people are too cold
You can take these practical steps to keep people as comfortable as possible when working in the cold:
- Provide adequate workplace heating, such as portable heaters, to ensure work areas are warm enough when they are occupied
- Design processes that minimise exposure to cold areas and cold products
- Reduce draughts while still keeping adequate ventilation
- Provide insulating floor coverings or special footwear when workers have to stand for long periods on cold floors
- Provide appropriate protective clothing for cold environments
You can also change work systems:
- Limit exposure by introducing systems such as flexible working patterns or job rotation
- Provide enough breaks to allow workers to get hot drinks or warm up in heated areas
When people are too hot
You can help ensure people are comfortable in warm conditions:
- Provide fans, such as desk, pedestal or ceiling-mounted ones
- Provide air-cooling or air-conditioning and adequate ventilation
- Ensure windows can be opened to keep air circulating
- Shade employees from direct sunlight with blinds or by using reflective film on windows
- Position workstations away from direct sunlight or sources of heat
- Place insulating materials around hot plant and pipes
- Provide cold water dispensers (water is better than caffeine or carbonated drinks)
You can also change work arrangements to avoid people getting too hot:
- Introduce flexible working patterns, such as job rotation, moving workers to cooler parts of the building where possible
- Allow enough breaks to allow workers to get cold drinks or cool down
- Relax formal dress codes – but make sure personal protective equipment is used if required
The HSE have advice on assessing the risks of heat stress and protecting workers from it.
PPE and workplace temperature
Personal protective equipment (PPE) reduces the body’s ability to evaporate sweat. If the PPE is awkward to wear, or heavy, it may contribute to an increase in body heat.
Wearing PPE in warm/hot temperatures with high work rates may increase the risk of heat stress.
How to keep workers safe wearing PPE
Encourage workers to remove PPE immediately after it is needed. This will prevent any heat retained in their clothing from continuing to heat them. Where necessary, they should allow it to dry out, or replace it, before using PPE again.
PPE may prevent workers removing clothing in case it exposes them to the hazard it is protecting them from.
Where PPE is required it can cause heat stress due to its weight and the fact that it prevents sweat evaporating from the skin. In these situations, employers should:
- allow slower work rates
- rotate staff out of this environment on a more frequent basis
- allow longer recovery times
- provide facilities for PPE to be dried so it can be worn again
- consider scheduling work to cooler times of the day
- review your risk assessment to see if automated or alternative systems of work can be introduced
- re-evaluate your equipment as newer PPE may be lighter and provide improved levels of protection and operator comfort
Make sure people continue to wear PPE correctly despite workplace temperatures. For example, they should not endanger themselves by undoing fasteners to increase air movement into clothing.
People can sometimes wear too much PPE so you should always look at the reasons for using it. For example:
- Can your workers wear less PPE and still have the protection they require or may other controls reduce or eliminate the need for it?
- Can the task be automated or can you adopt additional or more effective safeguards?
The HSE PPE at work pages provide further advice, including selecting the most appropriate equipment for your workplace.
Very high or low workplace temperatures
The HSE have specific advice for your workplace if you are working in very high or low temperatures, for example on heat stress, dehydration or cold stress.
If your workers are complaining or reporting illnesses that may be caused by temperatures in your workplace, review the situation and, if necessary, put in place controls to manage the risks. You may need to:
- monitor how workplace temperatures are affecting workers as part of your risk management
- put health surveillance or medical screening in place for workers who are pregnant, have illnesses or disabilities, or are taking certain medication
- review working habits and current practices and (where necessary) change these to control the risks
If you are not sure how to go about completing risk assessments for working in cold conditions please get in contact with competent Health and Safety specialists; Complisafe Health and Safety Consultants who can carry out risk assessments and train your team on how to complete suitable and sufficient risk assessments, call on 0333 577 2700.
