Crews in construction, utilities, agriculture and maintenance face two hazards in the same shift. Heat strain can become an emergency within hours. Solar ultraviolet (UV) radiation works slowly, and the damage to skin may not show for decades. Employers have good reason to focus on heat, given heat illness citations from the Occupational Safety and Health Administration (OSHA). The evidence on sun exposure suggests UV deserves its own line in the plan.

New findings presented September 30 at the European Academy of Dermatology and Venereology (EADV) Congress in Vienna add a climate dimension. The Global Access to Skin Health Observatory, run by the International League of Dermatological Societies (ILDS) with cosmetics maker L'Oréal Dermatological Beauty, drew on reporting from 136 countries. It found 42.6% had documented climate-related changes in skin disease, and 81% of those reported more heat rashes. The data describes national trends and does not isolate outdoor workers.

Occupational Sun Exposure Caused Nearly 19,000 Skin Cancer Deaths in 2019

The occupational toll is better measured. Joint estimates from the World Health Organization (WHO) and the International Labour Organization (ILO), published in November 2023, attributed 18,960 deaths from non-melanoma skin cancer in 2019 to sun exposure at work across 183 countries. Roughly one in three deaths from the disease fell into that group. The agencies counted 1.6 billion working-age people exposed while working outdoors, and attributable deaths nearly doubled after 2000.

Latency shapes prevention. Since skin cancer develops after years or decades of exposure, WHO and ILO say protection needs to begin early in a worker's career and continue throughout it. A heat plan that switches off when temperatures fall in autumn does little about a dose that builds all year.

WHO Recommends Sun Protection Once the UV Index Reaches 3

Thermometers are a poor guide to UV. WHO's ultraviolet radiation fact sheet notes that UV can be neither seen nor felt. Its intensity depends on sun angle, latitude, altitude and ozone, and water, sand or snow can reflect more of it onto skin. WHO advises protection whenever the UV Index hits 3 or higher. That level is public-health guidance, and no general workplace rule adopts it as a legal threshold.

Scheduling logic changes as a result. A cool shift can still bring meaningful UV exposure, and drinking water, which is central to heat prevention, does nothing for exposed skin. Overcast days still expose crews to UV, as the National Institute for Occupational Safety and Health (NIOSH) notes.

NIOSH's sun exposure guidance, last updated March 4, 2026, asks employers to schedule outdoor work when sunlight is weaker and to give crews shaded or indoor places to rest. It also calls for sunscreen rated at least sun protection factor (SPF) 15, reapplied every two hours and after heavy sweating. WHO ranks shade and clothing ahead of sunscreen, which it treats as backup for skin that fabric cannot cover.

Clothing complicates the picture. OSHA's heat hazard guidance warns that protective gear can trap heat, and its adjustment table adds 19.8°F (11°C) to heat-stress readings for workers in limited-use vapor-barrier coveralls. Where sun protection means more fabric, its thermal cost belongs in that assessment. The hottest regions face the sharpest version of that tradeoff, since wet-bulb conditions in the Gulf and South Asia already strain heat programs.

For environmental, health and safety (EHS) teams, this week's findings work best as a prompt to check whether shade, sunscreen supply and UV Index monitoring have named owners for the full outdoor season. Those duties can fall between functions when UV is folded into broader climate planning for operations and never assigned.