Preventing Heat Stroke in the Workplace This Summer

With the UK experiencing increasingly warmer summers, the risks of heat stress and heat stroke have become serious health and safety concerns. For employers, especially those with outdoor or physically demanding roles, it is essential to understand these risks and take preventive action in line with legislation and HSE guidance. This article provides guidance to help employers and workers stay safe, healthy, and compliant during hot weather.

What is Heat Stroke?

Heat stroke occurs when the body’s ability to regulate temperature fails, often following heat stress or exhaustion. It is a medical emergency. Symptoms include:

Confusion or disorientation
Fatigue
Cramps
Hot, dry skin (no sweating)
Nausea or vomiting
Rapid heartbeat
Loss of consciousness

Left unchecked, it can escalate into heat exhaustion or heat stroke.

Heat stroke is a medical emergency. Prompt cooling and hydration are critical, and emergency services must be contacted if symptoms become severe. According to guidance from the NHS and the HSE, early identification and intervention are key to preventing long-term harm.

Legal Responsibilities

Employers have a duty of care under the Health and Safety at Work etc. Act 1974 to ensure the health, safety and welfare of their staff. The Workplace (Health, Safety and Welfare) Regulations 1992 also require that indoor workplace temperatures are kept at a "reasonable" level.

Although there is no legal maximum temperature, the HSE states that employers must take action when working conditions pose a risk to health. Additionally, under the Employment Rights Act 1996 (Section 44), employees are legally protected if they remove themselves from dangerous conditions, such as extreme heat, after reporting it to their employer.

Key Employer Actions

Conduct Heat Risk Assessments

Employers must conduct thorough risk assessments, particularly during periods of hot weather. This includes evaluating the nature of the work, environmental conditions, physical activity levels and individual risk factors such as age, pregnancy, medical conditions or the use of certain medications.

Some individuals may be more vulnerable to heat-related illness, including those with cardiovascular conditions, the elderly, and people unacclimatised to hot environments. Employers should take appropriate steps to mitigate risks, such as adjusting workloads or shift patterns.

Evaluate

Work environment (indoor vs. outdoor).
Physical activity levels.
PPE requirements.
Individual vulnerabilities (e.g. medical conditions or pregnancy).

Implement Practical Controls

Adjust working hours to avoid peak heat times.
Provide fans, air conditioning, or shaded areas.
Ensure all staff have easy access to cool drinking water.
Encourage regular rest breaks in cool environments.

Adapt PPE and Dress Policies

Permit lightweight, breathable clothing.
Review PPE requirements to ensure they are suitable for hot conditions. For example, some PPE may be replaced with heat-tolerant alternatives, or workers can be permitted to remove PPE during breaks.
Provide sun protection (hats, long sleeves, sunscreen).

Education and Training

Employees should receive training on recognising the signs of heat exhaustion and heat stroke. Staff should also know how to respond if a colleague becomes unwell. Early symptoms of heat illness include headaches, weakness, excessive sweating, and nausea. Immediate action involves moving the person to a cool area, providing fluids and seeking medical help if symptoms persist or worsen.

Employers can implement buddy systems where workers monitor each other for early signs of heat stress. This is especially helpful in outdoor or isolated environments. In some cases, occupational health professionals may need to conduct regular health monitoring for high-risk individuals.

Outdoor Worker Considerations

Outdoor workers face elevated risks due to direct sun exposure and lack of cooling options. Employers should take extra precautions to safeguard these employees.

Provide shaded rest areas away from direct sunlight.
Supply sunscreen and promote regular application, especially for workers with fair or sensitive skin.
Allow flexible schedules to avoid working during peak heat hours, typically between 11 a.m. and 3 p.m.
Encourage the wearing of long sleeves and trousers made of lightweight, UV-protective materials.
Drinking water should be encouraged to prevent dehydration.

Skin cancer prevention should also be considered part of occupational safety for outdoor workers. Educational materials and reminders about sun protection are essential.

Vulnerable Individuals

Public health agencies including the UK Health Security Agency and NHS offer seasonal health campaigns to help individuals stay safe in high temperatures. Key messages include staying hydrated, avoiding excessive alcohol, keeping homes cool by closing blinds, and checking in on vulnerable neighbours or relatives.

People with pre-existing health conditions should be particularly cautious and may need additional support from employers, carers, or healthcare professionals.

Special attention should be given to:

Older adults
Pregnant employees
Those on certain medications or with chronic health issues

These individuals may require additional hydration breaks, adjusted duties, or even temporary reassignments during extreme temperatures.

Why It Matters

In recent years, the UK has experienced record-breaking temperatures exceeding 40°C. Climate change is expected to make extreme heat events more frequent and severe. Heat-related illnesses contribute to increased emergency admissions, absenteeism, reduced productivity and in some cases, fatalities.

By taking proactive steps to address heat stress risks, employers not only fulfil legal obligations but also protect the wellbeing and morale of their workforce.

Encourage hydration by placing reminder posters around the workplace. Something as simple as “Drink before you're thirsty!” can reduce the risk of dehydration and heat-related incidents.