What it regulates and what needs distinction
NOM-015-STPS-2001, listed as current in the official catalogue, addresses occupational exposure to high and low thermal conditions in Mexico. It is not an office comfort standard and does not establish one ambient temperature safe for every activity. It connects with heat stress through conditions affecting the body’s thermal balance.
The text distinguishes exposure sources and gives climatic conditions particular treatment in section 5.10. All industrial-process assessment duties should therefore not be transferred without qualification to every outdoor situation. This distinction does not mean that outdoor work is risk-free or carries no preventive duties.
Recognise the task and its cycles
Recognition identifies sources, open or enclosed areas, ventilation, exposed people, activities and durations. Physical effort matters: two people in the same environment can have different thermal demands when one is seated and the other performs strenuous work.
Assessment records should identify conditions, instruments, calibration, clothing or protection and existing controls. Different indices are used for heat and cold. Air temperature alone does not describe every heat exchange or establish universal recovery periods suitable for all workers.
Control exposure and check the outcome
Decisions must consider the source, process, location, work demands and characteristics of exposed people. Where applicable criteria are exceeded, the standard requires controls and immediate protection while the intended solution is implemented. A subsequent assessment must verify the effectiveness of the measures.
Acclimatisation forms part of requirements for certain heat exposures and distinguishes initial assignment from return after absence. It should be built into work planning, not used as an argument for maintaining uncontrolled exposure or ignoring a changed task.
Information and health follow-up
Personnel need to understand hazards and measures and be able to report changes during work. Health surveillance follows clinical judgement and the applicable framework. The report should keep recognition, assessment and controls consistent with the current job.
This entry does not prescribe individual breaks, hydration, diagnosis or treatment. Its purpose is to prevent an isolated table or weather application from replacing the technical and medical assessment needed for the particular scenario and the actual people exposed.
