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Working in Heat and Cold Conditions

Health & Other Issues

Heat stress is a genuine medical emergency. But in the UK it is usually only an occupational health risk for those whose natural cooling mechanisms are affected by aspects of their work. For example, it can affect those obliged to work while clothed in heavily-insulating personal protective equipment, those working in roof or similar spaces where humidity could become excessive, or those doing strenuous physical labour, especially in direct sunlight and away from sources of fresh water. Additional thought should be given to protecting these workers.

For those in the UK doing non-strenuous indoor work, high temperatures are typically more of an unpleasant inconvenience rather than a genuine health risk. It can help to stay in the shade, maximise ventilation, and wear lightweight, loose clothing to help perspiration evaporate and thereby provide its cooling effect. It is important to consume plenty of water to prevent dehydration.

A minority of people with significant pre-existing health conditions may be advised to take extra care by their medical professionals. Hot weather places a strain on the heart and lungs and for that reason the majority of serious illness caused by heat are respiratory or cardiovascular.  Older people and children are particularly at risk.

The Met Office advises of an increased chance that some heat-sensitive systems and equipment may fail, leading to power cuts and the loss of other services to some homes and businesses. Some delays to road, rail and air travel are possible, with potential for welfare issues for those who experience prolonged delays. Please give additional thought to staff (and students) who may be travelling for work or fieldtrips. Consider if their journeys are necessary and how they can access plenty of water and shade in case of delays.

In the event of a related or unrelated major incident affecting the University during this period, please give additional thought to if and how extreme weather might affect the University’s response.

General advice - Make sure you know what to do

For those working outdoors:

  • Schedule working to earlier and cooler times of the day where possible.
  • Consider reviewing the frequency of job rotation.
  • Plan more frequent breaks.
  • Stay hydrated, carry drinking water in vehicles or with work equipment.
  • Apply a high factor sun scream (>SFP 15), avoid exposed skin, and wear a hat with a brim.
  • Work in the shade if possible.
  • Remove protective clothing during breaks to encourage cooling.
  • 8. Recognise the symptoms of heat stress: inability to concentrate, heat rash, severe thirst,giddiness, nausea, fainting, muscle cramps.

For those of working indoors in warm spaces:

  • Minimise the time spent in hot environments, e.g. glass houses, kitchens, roof spaces.
  • If working in hot environments: plan more breaks and increase the frequency of job rotation.
  • Stay hydrated by carrying drinking water or know of the nearest supply.
  • Report heat stress to your line manager

For those of working in offices

  • Reduce heat build-up: turn off any unnecessary electrical equipment (esp. power adaptors) when not in use, set your monitor to sleep after no more than 1 5 mins to reduce power consumption, switch off lighting when not needed, draw blinds to limit solar input and prevent glare to computer monitors.
  • Increase ventilation: opening windows, open doors - fire doors must be shut when areas are unoccupied, or the fire alarm sounds, use fans provided - avoid trailing cables and trip hazards.
  • Stay hydrated: regular drinks of cool water and take breaks away from your computer workstation.
  • Try to keep your environment cool, closing blinds or curtains can help.

Other useful advice:

  • Try to keep your environment cool, closing blinds or curtains can help.
  • At night, keep your sleeping area well ventilated. Night cooling is important as it allows the body to recuperate.
  • Try to stay cool by taking cool showers or baths and/or sprinkle yourself several times a day with cold water.
  • Avoid too much exercise when very hot, which can cause heat exhaustion or heat stroke, and watch for signs of heat stress - an early sign is fatigue. If you do go out for exercise or outdoors, try to avoid the hottest part of the day (11 am to 3 pm) and seek shade where possible.
  • Drink plenty of fluids, but not alcohol, which dehydrates the body.
  • Try to eat as you normally would. Not eating properly may exacerbate health-related problems.
  • Keep your vehicle well ventilated to avoid drowsiness. Take plenty of water with you and have regular rest breaks.
  • Watch out for vulnerable colleagues and others on campus and check in with them regularly.
  • Avoid being in the sun for long stretches. Wear lightweight, light-coloured clothing, high factor sunscreen and a wide-brimmed hat.
  • Reapply an appropriate factor sun cream at regular intervals during the day. The UV index (the strength of the sun) can be high at many times of the year - it doesn't have to be hot. The UV index can be strong through cloud even when the sun isn't directly shining.

Working in cold conditions:

Those working outdoors are at greater risk from cold than those indoors due to wind chill and low temperatures. The weather can have a serious impact on a worker’s health if the risks have not been properly managed. Outdoor cold conditions can also affect a worker’s ability to keep safe, for example when handling machinery.

Managers should assess the risk of outdoor working and ensure staff and volunteers are aware of the measures in place.

There are simple actions to take to protect people working outdoors in cold environments:

  • Monitor weather forecasts and plan work, accordingly. Be prepared to adapt plans. (See weblinks).
  • Consider scheduling work, potentially delaying work until warmer weather or more favourable conditions, without compromising safety.
  • Where possible arrange breaks in a warmer refuge.
  • If working off-site, where possible provide mobile warming up facilities with access to warm drinks. If this is not possible, encourage workers to bring their own flask with a warm drink.
  • Introduce more frequent breaks.
  • Dress appropriately to protect core extremities such as hats and gloves; these should be compatible with PPE requirements.
  • If work requires stationary periods, get up and move around periodically.
  • Ensure there is access to warm drinks or instruct workers to bring warm drinks in flasks if working away from comfort area.
  • Understand the early symptoms of cold stress such as coughs and body aches.

Open Water:

Outdoor workers and volunteers should be made aware of open water hazards and the risks. Cold water shock can have a dramatic effect on the body. Anything below 15°C is defined as cold water, therefore there is a significant risk of it occurring when entering the water at any time of year, including in the summer. For guidance the average UK Sea temperatures are just 12°C and rivers colder. Managers should assess the risk to staff and volunteers when working in areas close to open water and communicate measures in place.

Cold Conditions indoors:

If conditions indoors are considered too cold, staff should talk to a manager or HSC who can raise with Estates.

Staff and students must not bring their own heaters into UoR and additional ones must not be purchased. If agreed by a manager that there is a genuine need, heaters are to be obtained through Estates raising a WREN in the first instance. In this event, oil heaters should be used, please refer to Cooling and Heating Policy Our Policies and Procedures - Building Maintenance - FMD  


KM, June 2024