Ultraviolet protection factor of work garments with respect to UV radiation exposure of outdoor workers

Construction workers are frequently exposed to high solar ultraviolet radiation (UVR), and clothing is a key pillar in their protection from adverse effects of UVR. However, clothing does not shield UVR fully and only reduces the transmitted UVR. Depending on the amount of exposure, this transmitted UVR may be detrimental. We therefore investigated the Ultraviolet Protection Factor (UPF) of 35 non-UPF-certified garments, including shirts, billed caps, and neck guards, provided by construction companies. Additionally, the personal UVR exposure of highly exposed construction workers was measured below the nape. Our measurements showed that the garments' UPF varies from UPF 5 to 431 and correlates with an item's areal density. The personal exposure was 22 SED/day on average, but the highest measured daily exposure was 44 SED, corresponding to 90% of ambient UVR. From this, we calculated the remaining radiant exposure through the garments and found about half the provided shirts and 65% of all items would reduce this exposure to nonhazardous 1 SED/day or less. When considering a personal UVR exposure of close to 100% of ambient UVR, we recommend that clothing items for outdoor workers must provide a UPF of 80+, which is higher than current standards certify.