Too Hot to Work?


It may not have been too much of a concern given the British weather for the last few months, but with the the recent hot weather (which is typically disappearing as I write),  the thoughts of construction health & safety managers, or of anyone responsible for a team working outdoors or in cramped site cabins, should turn to the protection of their staff and of contractors under their direction.

There is no actual legal limit for how hot it can be in enclosed premises, but it must be ‘reasonable’. The HSE gives a guideline maximum as being 300 C / 860 F, or less if the work taking place is strenuous.

Indoors, the sort of precautions that should be taken to limit exposure include shading windows, providing air cooling, moving work away from direct sunlight and providing regular work breaks.

Outdoors, where of course much building work takes place, the issue is more severe. Bear in mind that when you see a weather forecast it is quoting shade temperatures, and 300 C is easily achieved in the glare of the sun on an exposed work site.

The sorts of problems encountered by workers in such conditions include an increased heart rate and strain on the system: dehydration due to excess sweat production: lack of concentration leading to errors and accidents: heat rash: muscle cramps: heat stroke: and fainting.

PPE Conflicts

Personal Protective Equipment (PPE) can be a factor: it is needed for a lot of construction and demolition work but it can build up body heat. If there is a conflict between a requirement for PPE and a need for cooling, it is all the more reason for a risk assessment to be carried out. It is wise to involve a trained specialist such as a McCormack Benson Health & Safety consultants, who will know what breathable PPE is available, how much is actually necessary, the level of climatic risk and the work rates involved, what other measures can feasibly be taken, and when the services of a health professional are needed.

Some of the suggested measures for outdoor working in Summer are:

  • Schedule more frequent work breaks
  • Provide shade during breaks
  • Ensure that PPE is removed during rest time
  • Restrict work in the hottest part of the day
  • Supply ample free cool water
  • Educate workers about the risks of heat stress

The sun is dangerous, especially to fair-skinned people, and it is recommended that workers wear SPF15 or higher sunscreen as well as wearing a hat to protect their ears and the back of their neck. Of course many construction workers will be wearing a helmet.

Water, Water Everywhere…

The recommendation about taking on plenty of water is especially critical. It is considered ideal for manual workers to consume 250ml (half a pint) every 15 minutes or 500ml (a pint) every half hour. If this is not feasible, an acceptable alternative is to take 500ml before starting a shift and stopping every hour to drink 500ml in a break time.

Do not be seduced into counting fizzy drinks, tea or coffee in this allowance: they can actually dehydrate you. Only pure water supplies the necessary hydration protection.

Forewarned is forearmed, and on a construction project of any size you will be involved in appointing a CDM Co-ordinator, who should include in his or her remit the planning for any seasonal work that should be pre-organised to take account of the possibility (remote as it may seem in some British seasons) that heat risks may be encountered.