The UK is experiencing hotter, longer, and more frequent heatwaves — a trend that is expected to intensify over the coming years. High temperatures don’t just cause discomfort; they create real health and safety risks that employers are legally required to manage.
This blog breaks down:
- The legal duties under UK health and safety law.
- Employer responsibilities during hot weather
- Employee responsibilities
- Guidance on breaks, hydration, ventilation, PPE, and communication
- Practical steps to keep workplaces safe
☀️ 1. Why Heatwaves Are a Workplace Risk
Heatwaves increase the likelihood of:
- Heat exhaustion and heatstroke
- Dehydration
- Reduced concentration and increased human error
- Fatigue‑related accidents
- Skin damage from UV exposure (for outdoor workers)
- Equipment overheating or malfunctioning
These risks affect all sectors, but especially, Construction, Warehousing and logistics, Manufacturing, Agriculture, Hospitality, Transport and Office environments with poor ventilation.
⚖️ 2. The Legal Framework: What the Law Requires
Several UK laws apply to heatwave safety:
Health and Safety at Work etc. Act 1974
Employers must ensure the health, safety, and welfare of employees so far as is reasonably practicable.
Management of Health and Safety at Work Regulations 1999
Employers must carry out suitable and sufficient risk assessments, including environmental risks such as heat.
Workplace (Health, Safety and Welfare) Regulations 1992
Workplaces must have a reasonable temperature. There is no legal maximum temperature, but employers must take action when conditions become unsafe.
Personal Protective Equipment at Work Regulations 1992
PPE must be suitable for the conditions — including heat.
Employees must receive adequate rest breaks, which may need to be increased during extreme heat.
🏢 3. Employer Responsibilities During a Heatwave
Employers have a duty to anticipate, assess, and control heat‑related risks. Key responsibilities include:
Heat Risk Assessment
Review:
- Indoor temperatures
- Ventilation and airflow
- Humidity
- Physical demands of tasks
- PPE requirements
- Outdoor exposure
- Vulnerable workers (pregnant workers, those with medical conditions)
Temperature Control Measures
Employers should implement:
- Fans, air‑conditioning, or portable cooling units
- Shaded areas for outdoor workers
- Adjusted working hours (e.g., earlier starts)
- Reduced physical workloads
- Relaxed dress codes where safe
Hydration and Breaks
Provide:
- Easily accessible drinking water
- More frequent rest breaks
- Cool rest areas
Communication and Training
Employees must be informed about:
- Heat‑related symptoms
- Emergency procedures
- Hydration expectations
- PPE adjustments
- Reporting concerns
Monitoring and Review
Conditions can change rapidly. Employers should:
- Monitor indoor and outdoor temperatures
- Review controls daily
- Record actions taken
👷 4. Employee Responsibilities
Employees also have duties under UK law.
Follow Safety Instructions
Workers must comply with heat‑related controls, including:
- Taking breaks
- Wearing modified PPE
- Staying hydrated
Report Symptoms Early
Employees should report:
- Dizziness
- Nausea
- Excessive sweating
- Confusion
- Headaches
Early reporting prevents serious incidents.
Use Equipment Safely
Heat can affect machinery. Employees must:
- Report overheating equipment
- Follow shutdown procedures
- Avoid bypassing safety controls
🧊 5. Breaks, Hydration & Rest: What Good Practice Looks Like
During a heatwave, employers should consider:
- Breaks every 30–60 minutes for high‑intensity work
- Cool rest areas away from direct sunlight
- Unlimited access to drinking water
- Electrolyte drinks for strenuous outdoor work
- Rotating tasks to reduce heat exposure
- Earlier or later shifts to avoid peak temperatures
Outdoor workers may need:
- UV‑rated clothing
- Sunscreen
- Shaded rest zones
📣 6. Communication: The Most Important Control
Clear communication prevents accidents. Employers should:
- Issue heatwave bulletins
- Brief teams at the start of each shift
- Display posters on heat stress symptoms
- Use WhatsApp/Teams/SMS alerts for outdoor teams
- Encourage a “speak up” culture
Workers must know:
- What symptoms to look for
- Who to report to
- What to do in an emergency
🧭 7. Practical Heatwave Controls Checklist
Heatwave Readiness Checklist
- Risk assessment updated
- Temperature monitored
- Ventilation checked
- Cooling equipment available
- Hydration stations set up
- Break schedule adjusted
- PPE reviewed
- Outdoor shade provided
- Communication plan active
- Vulnerable workers identified
- First aiders briefed on heat illness
🌡️ 8. Final Thoughts: Heatwaves Are Now a Predictable Risk
Heatwaves are no longer rare events — they are a foreseeable hazard. That means employers must plan for them just as they would for any other workplace risk.
A proactive approach protects:
- Employee health
- Productivity
- Legal compliance
- Business continuity
Contact us should you wish to find out more or request a risk assessment.
