The task determines lighting needs
NOM-025-STPS-2008 is listed as current in the official catalogue. It establishes lighting conditions for areas and visual tasks in Mexican workplaces. It does not impose one level throughout an installation: recognising an aisle is different from inspecting a small, low-contrast component.
Workplace lighting needs assessment in relation to the activity. Counting luminaires or knowing their wattage does not demonstrate that adequate light reaches the working plane. Excessive light and reflections can also impair vision even where an illuminance reading is high.
Recognition before measurement
Recognition identifies areas, workstations, tasks, equipment and luminaire arrangement, surfaces and local lighting needs. It includes workers’ reported perceptions. Shadows occurring in the normal working posture may be missed during a visit when the workstation is unoccupied.
For example, moving a desk or installing shelving can change effective lighting without replacing a single lamp. The study should be updated when the characteristics determining assessed conditions change, rather than relying only on the date when luminaires were purchased.
Measurement and glare
Assessment follows the standard’s methods and compares each task with the relevant criterion. Alongside illumination levels, it considers the reflection factor of surfaces affecting the workstation. The report should establish where, when and under which conditions results were obtained.
A general building average is insufficient if a critical task remains poorly lit. Decisions should connect findings with specific actions and verify that a solution does not introduce new reflections or obstruct another nearby activity. The final arrangement must suit real use.
Maintain conditions and anticipate failure
The maintenance programme covers luminaires and emergency systems. Emergency lighting is required where interruption could create risk in a visual task or on evacuation routes requiring it. It needs to retain its function when the normal supply fails.
The standard addresses visual examinations for people working under special lighting within its scope. This does not mean the identical test is required for every worker. This entry supports assessment and documentation; it does not replace lighting engineering design or individual clinical evaluation.
