Extreme heat and operational risk: how to protect workers during heat waves

Operational risk related to extreme heat is one of the most underestimated occupational risks. Yet, every summer, heat waves put thousands of workers at risk on construction sites, in warehouses, in fields and in factories. It’s not a matter of bad luck. It’s a question of prevention.

Why heat is a real operational risk

High temperatures are not just an inconvenience. They directly impact the physical and cognitive abilities of workers.

When body temperature exceeds physiological limits, the body begins to give signals: early tiredness, decline in concentration, slowing of reflexes. In a work environment, these effects translate into human errors, accidents and injuries.

In Europe, studies confirm that workplace injuries increase significantly during heat waves. Workers exposed to high temperatures for prolonged periods are among the most at risk, especially those who work outdoors, in non-air-conditioned environments or near industrial heat sources.

The most vulnerable workers

Not all workers are exposed to the same risk. Some categories are particularly vulnerable :

Construction workers and agricultural workers, exposed directly to the sun for many hours. New hires, whose bodies are not yet acclimatized to summer working conditions. Elderly workers and those suffering from chronic pathologies, for whom thermal stress can have more serious consequences. Finally, those who take certain drugs that interfere with body thermoregulation.

How to recognize warning signs

Prevention begins with recognizing the symptoms. The main signs of heat stress are:

Sudden and disproportionate tiredness compared to the effort, Persistent headache Nausea and dizziness, Mental confusion and difficulty concentrating, Muscle cramps, Red, hot and dry skin

When one or more of these signs appear, immediate action is needed. Stop-Work is not a weakness. It is a choice of responsibility.

5 concrete measures to protect workers

1. Adapt working hours On the hottest days, plan the most physically intense activities in the early hours of the morning or late afternoon, avoiding the most critical time slots between 12 and 4pm.

2. Ensuring proper hydration In intense heat, water needs increase significantly. The general rule is to drink about a liter of water every hour of working outdoors — without waiting for the feeling of thirst, which always arrives too late.

3. Arrange regular breaks in cool places Breaks are not optional. They are a security measure. Every worker exposed to heat must have access to shaded areas or cool environments in which to recover.

4. Train and raise awareness for the whole team Workers must know the risks, recognize the symptoms and know how to intervene — both for themselves and for their colleagues. Training on heat risk must be an integral part of the company’s HSE program.

5. Document and report every episode Every episode of heat-related discomfort, even mild, must be recorded and analysed. Incident traceability is the basis for improving procedures and preventing future episodes.

The regulatory framework

In Italy, Legislative Decree 81/2008 requires the employer to evaluate all risks to the health and safety of workers — including the risk of thermal stress. On days of extreme heat, companies can request the Redundancy Fund (CIG) to temporarily suspend the riskiest activities.

Knowing and applying these provisions is not just a legal obligation. It is a responsibility towards people.

Conclusion

Extreme heat is not a fatality. It is a predictable, measurable and manageable risk — like all other operational risks.

Adapt schedules, ensure hydration, train the team, document episodes. They are simple actions. But they make the difference between a worker who returns home healthy and one who doesn’t.