GMB members who work outdoors face some very clear dangers from hot work and exposure to sunlight. There is an increased risk from sunstroke, sunburn and heat exhaustion particularly when work is physically strenuous. The effects of high temperatures are made worse by other environmental factors. Heat stress is more likely to occur if the air is humid, the airs still, there is direct heat radiation and the exposure is for long periods. Some of the effects are:

Skin cancer

This is now one of the most common cancers in the UK with incidents still rising. It has been estimated that 80% of cases could be avoided. On average outdoor workers receive 3 to 4 times more Ultra Violet (UV )Radiation exposure than those that work indoors. This cumulative exposure puts outdoor workers at much greater risk of contracting skin cancer.

Heat stress

Too much heat increases fatigue and can cause extra strain on the heart and lungs. The physical symptoms to look for include:

• Inability to concentrate
• Clammy skin
• Rapid pulse
• Muscle cramps, nausea and vomiting
• Heat rash –”Prickly heat”
• Headaches and blurred vision
• Dizziness and fainting
• Fatigue and light headedness

A late symptom of heat stress can often be severe thirst Heat stress can in turn lead to heat stroke

Heat stroke

This is much more serious than heat stress and symptoms can include:

• Hot dry skin, as sweating stops
• Confusion
• Convulsions
• Loss of consciousness

Obviously the latter is extremely serious and could result in death. This condition requires immediate medical treatment. It will take at least 30 minutes to cool the body once it has overheated.

Other problems

Prolonged exposure to the sun can also lead to skin ageing more rapidly. In the long term eye sight problems are also associated with radiation exposure and glare.

As the employer has a clear legal duty to provide you with a safe and healthy workplace there is a need to carry out a risk assessment to determine the extent of the problem which might affect you. From this risk assessment action should be taken to reduce the extent of the problem. Some areas that should be considered are:

• Any clothing supplied, should be loose fitting and of a close woven fabric
• The supply of hats and neck protection should be considered
• The supply of sunscreen, which should be high protection (15 plus)
• Encourage the taking of frequent breaks
• Supply free cold drinks

If possible arrange the working day so that at the time of greatest heat, generally between 11am and 3pm, there is an opportunity to work in the shade.

Rising temperatures increases the likelihood of fatigue which in turn leads to an increase in accidents. As the temperature goes up people sweat without moving, stress levels rise, concentration levels fall, mistakes increase, productivity goes down and accident levels rise.

In addition, if you are doing manual work there is a greater loss of fluids leading to dehydration and potential heat stress as the core body temperature rises. All of these problems become worse if the humidity is also high. When the body is unable to cool itself through sweating as the air is already loaded with moisture

Surprisingly there is no legal maximum temperature for working indoors. The Workplace (Health, Safety and Welfare) Regulations 1992 state that temperatures within workplaces must be reasonable.

To say that this phrase is open to interpretation by many employers would be an understatement. GMB feels, in line with the World Health Organisation that a suitable maximum would be 25°C (75°F).

The Chartered Institute of Building Service Engineers recommend that a suitable range of indoor temperatures should be between 13°C and 23°C depending on how strenuous the work involved may be. Some examples include:

• Heavy work in factories 13°C
• Light work in factories 16°C
• Hospital wards and shops 18°C
• Offices and dining rooms 20°C.

In addition, thermometers should be available at convenient distances from every part of the workplace to enable temperatures to be measured.

To enable your workplace to have a reasonable temperature your employer should take the following measures:

• Provide good ventilation, which should consist of a flow of fresh or purified air. Open windows can sometimes supply this but there may be a need for this to be provided by mechanical means.
  
  This can be achieved by providing air cooling plant or air conditioning units. If temporary cooling units are used these should be replaced on a permanent basis to avoid annual disagreements over their supply.
   
• Windows can be shaded to deflect direct heat and glare and is a relatively cheap method to use.
   
• Insulation of buildings should be considered, which helps keep heat out in summer and heat in during winter.
   
• The provision of free cold drinks and the ability to take extra breaks, preferably in cooler areas.
   
• The relaxation of any formal dress codes or the insistence on the wearing of heavy uniforms.

GMB safety representatives should use their rights(under the Safety Representatives and Safety Committee Regulations 1977) to get involved with any risk assessments to make sure their experience and practical knowledge is incorporated in the introduction of any safety measures designed to reduce exposure to sunlight or heat.

They should:

• Ensure the employer plans for summer temperatures before it becomes a problem, and this should be done through the safety committee.
• Raise any complaints about the temperature or heat with the employer on behalf of the members.
• Report any ill health effects from heat excess in the accident book. Where management refuse to take any measures to reduce heat or alleviate the symptoms of excessive temperatures take collective grievances on behalf of the workforce and involve GMB Officers

Click here for full PDF guide and reps' checklist