Managing Workplace Temperature in Hot Weather: A Guide for Small Businesses

Natural ventilation and fans in a workspace

Hot weather can create uncomfortable and even unsafe conditions in the workplace. When temperatures rise, productivity often drops, and employees may face health risks such as heat exhaustion or dehydration. Managing workplace temperature effectively during warm months is essential to maintain comfort, safety, and efficiency. Here are some practical strategies to keep indoor environments cool and pleasant when dealing with the challenges of hot weather.

What does the law actually say?

The Workplace (Health, Safety and Welfare) Regulations set a minimum temperature of 16°C for sedentary work, or 13°C for work involving significant physical activity. There is no legal maximum temperature but the HSE does give specific advice to manage heatwave temperatures.

Most effective controls are low-cost or no-cost. Here are the measures that make the biggest difference:

• Improve airflow. Open windows and doors where possible. Use desk or floor fans to move air around. For areas with persistent heat build-up — a kitchen, server room, or south-facing office — consider a portable air cooler.

• Reduce solar gain. Blinds and window coverings can make a significant difference to rooms with large south or west-facing windows. Repair or replace blinds when they become faulty so they always remain effective during hot weather.

• Adjust working patterns. If you have flexibility, schedule physically demanding tasks for early morning or late afternoon. Allow more frequent rest breaks during hot spells, and rotate staff on particularly hot jobs.

• Provide cold drinking water. This sounds obvious, but the requirement is that it's freely available and easily accessible — not just technically present somewhere in the building.

• Relax the dress code. Where PPE or customer-facing standards allow it, let staff wear lighter clothing during hot weather.

  
  

Your most vulnerable employees need individual attention

Some staff may be more susceptible to heat-related illness than others. Pregnant workers, older employees, those with conditions like heart disease, diabetes or respiratory illness, and anyone taking medication that affects temperature regulation can all be at significantly higher risk. Identify if anyone may be affected and establish what additional support may be necessary.

Recognising and responding to heat illness

Make sure your staff — and especially anyone in a supervisory role — can recognise the difference between heat exhaustion and heat stroke.

Heat exhaustion produces heavy sweating, weakness, pale or clammy skin, a weak pulse, nausea and possible fainting. Move the person somewhere cool, have them lie down and loosen their clothing, apply cool damp cloths, and get them to sip water slowly. Most people recover with these measures.

Heat stroke is a medical emergency. Signs include a very high body temperature, hot dry skin, a rapid strong pulse and confusion or loss of consciousness. Call 999 immediately. Do not give fluids to someone who is unconscious.

A note on documentation

If a member of staff raises a formal complaint about temperature, or if the HSE were ever to visit, you want to be able to show that you identified the risk and took reasonable steps to address it. Therefore make sure you incorporate the relevant controls into your workplace risk assessment.

If you require a hot weather policy or risk assessment please get in touch.