In the UK there is no specific temperature at which you have an automatic legal right to refuse to work, either for heat or for cold. Instead, the law says your employer must keep the workplace at a ā€œreasonableā€ temperature and manage any risks from hot or cold conditions.

What the law actually says

  • The Workplace (Health, Safety and Welfare) Regulations 1992 require indoor workplaces to be kept at a ā€œreasonableā€ temperature during working hours, but they do not set fixed minimum or maximum figures.
  • Health and Safety Executive (HSE) guidance suggests at least 16Ā°C for most indoor work and 13Ā°C if the work is physically demanding, but these are guidelines, not hard legal limits.

Minimum and maximum temperatures

  • Minimum: HSE guidance:
    • 16Ā°C for mainly deskā€‘based or light work.
* 13Ā°C for work involving rigorous physical effort.
  • Maximum: There is no legal maximum working temperature in UK law, even in heatwaves. Employers must instead assess the risk and take steps (ventilation, breaks, hydration, PPE, etc.) to keep conditions safe and reasonably comfortable.

So when can you refuse to work?

You do not get a simple ā€œitā€™s X degrees so I can go homeā€ rule, but you may be able to stop work if:

  • Conditions pose a serious and imminent danger to your health or safety (for example, extreme heat causing heat stress or heatstroke, or extreme cold causing clear risk of hypothermia).
  • Your employer ignores clear risks and fails to take reasonable measures after you raise concerns (for example, no ventilation, no breaks, no water, or no protection in very cold conditions).

In those situations, general health and safety law and protections from detriment for raising safety concerns may apply, but whether refusal to work is justified depends on the specific facts and evidence, not a single temperature number.

Practical steps if itā€™s too hot or too cold

If you feel it is unsafe or unreasonably uncomfortable:

  1. Record conditions
    • Note thermometer readings, time of day, and how long you are exposed.
 * Keep a log of symptoms (dizziness, headache, shivering, numb fingers, etc.).
  1. Raise it internally first
    • Speak to your manager, HR, or health and safety representative and point to HSE guidance on 16Ā°C/13Ā°C and the duty to keep temperatures reasonable.
 * Suggest adjustments: fans or heaters, more breaks, rota changes, different PPE, shaded or warmer areas, temporary homeā€‘working, or altered start/finish times.
  1. Escalate if needed
    • Use your companyā€™s formal grievance or health and safety reporting channels if nothing changes.
 * For persistent serious risk, employees can seek advice from a union, an employment solicitor, or HSE/Acas about rights to refuse unsafe work in ā€œserious and imminent dangerā€ situations.

Key takeaway

  • There is no fixed UK temperature where you can automatically refuse to work, but employers must keep conditions reasonable and manage risks from heat and cold.
  • If temperature is making you unwell or clearly unsafe, you should raise it as a health and safety issue and, in serious cases, get formal advice before refusing to work.

Information gathered from public forums or data available on the internet and portrayed here.