Many leaders believe that heat regulations are simply a matter of providing bottled water and waiting for the heatwave to end. The decree of May 27, 2025, has changed the game more profoundly than it might seem, and on one particular point that deserves your attention.
The two-line frame
Decree No. 2025-482 of May 27, 2025, entered into force on July 1, 2025. It creates in the Labour Code an entire chapter dedicated to the prevention of risks related to episodes of intense heat, in articles R. 4463-1 to R. 4463-8.
A decree of the same day defines the triggering thresholds, based on the Météo-France vigilance system.
Since then, no new text has modified this foundation. The texts published in 2026 supplement and equip it, but do not replace it.
The most significant change consists of four words that have been removed.
Article R. 4225-1 of the Labour Code, which deals with outdoor workstations, has always included the phrase "where possible".
It has been removed.
Consider the implications of this. This formula used to be the universal excuse, the one that allowed people to reply that they would have liked to make improvements, but it wasn't feasible. It no longer exists. Adapting outdoor work areas to protect workers from the effects of weather conditions is now a firm obligation.
If your business involves outdoor work, that's the key takeaway from this whole article.
Water, but not just for drinking
Article R. 4225-2 has also been rewritten. The employer must provide fresh drinking water, not only for drinking, but also for quenching thirst and refreshing oneself.
The nuance opens up to means of bodily refreshment, which is something other than a water fountain.
On construction sites, a specific rule applies. When running water cannot be provided, the employer must make available a minimum of three liters per day per worker.
What you need to do, specifically
A risk assessment related to intense heat is mandatory, both indoors and outdoors. Many office and workshop businesses believe they are exempt from this requirement. They are not. And this assessment must be included in your single risk assessment document.
The decree then lists eight preventive measures: modifying processes, adapting premises and workstations, adjusting work organization, particularly schedules, implementing technical measures such as insulation or solar radiation reduction, providing increased quantities of fresh water, using equipment to maintain a stable body temperature, adapting personal protective equipment, and informing and training workers. Two specific obligations deserve emphasis. Measures must be adapted to vulnerable workers, due to age or health condition, and this is done in conjunction with the occupational health and safety service. Furthermore, you must organize the reporting of any concerning physiological signs and the provision of emergency assistance, paying particular attention to isolated workers.
Finally, on construction sites, heat must be taken into account in prevention plans and coordination documents.
The most frequent error: the trigger level
The decree defines three levels of vigilance: yellow, orange and red.
Specific obligations are triggered at the yellow level. Not orange.
Yellow corresponds to a short-lived heat spike, or to persistent heat affecting vulnerable populations due to working conditions or physical activity. In other words, precisely your topic.
The confusion arises from the fact that orange and red alert levels qualify as heatwave conditions for compensation purposes during work stoppages in the construction industry. These are two separate issues, and many companies confuse them.
No, the Labor Code does not specify a maximum temperature
This is the question I get asked most often, and the answer is surprising. There is no temperature beyond which work is prohibited by law.
The values you may have heard, around 28 degrees for physical work and 30 degrees for office work, are guidelines published by the INRS (National Institute for Research and Safety). These are useful guidelines, but they have no regulatory value.
What is legally binding, however, is your obligation to assess and act. And a key clinical indicator to be aware of: heatstroke has a fatality rate of fifteen to twenty-five percent. It is not a minor ailment; it is a life-threatening emergency.
Why this is no longer a summer topic
The year 2026 had fifty-two days of heat waves in France, an absolute record, ahead of thirty-three days in 2022 and twenty-two days in 2003. July 2026 was the hottest month ever recorded.
Above all, the State has included in its national adaptation plan a reference trajectory of plus four degrees in metropolitan France by 2100.
Translation for a business leader: the summers we've just experienced aren't accidents we need to recover from. They're the normal summers of the coming decade. If your heatwave plan is a crisis plan, it's poorly designed. It needs to become a structural plan, decided upon during the design of buildings, workstations, and schedules, not in the heat of July.
KEY POINTS TO REMEMBER
- Decree No. 2025-482 of May 27, 2025 creates Articles R. 4463-1 to R. 4463-8 of the Labour Code.
- The phrase "where possible" has been removed from article R. 4225-1: the development of outdoor posts becomes a firm obligation.
- Heat risk assessment is mandatory both indoors and outdoors, and must be included in the single document.
- The obligations are triggered as soon as the alert level is YELLOW, not orange.
- The French Labor Code does not specify a maximum temperature. The reference temperatures of 28 and 30 degrees Celsius come from the INRS (National Institute for Research and Safety) and are not legally binding.
TO GO FURTHER
Does your single document address heat loss item by item, or in a single general line? The difference is immediately apparent during an inspection. Contact us to discuss this further.
