Backes Claudine, Religi Arianna, Moccozet Laurent, Vuilleumier Laurent, Vernez David, Bulliard Jean-Luc
Institute for Work and Health, University of Lausanne and Geneva, Lausanne, Switzerland.
Centre Hospitalier Universitaire Vaudois, University Institute of Social and Preventive Medicine (IUMSP), University of Lausanne, Lausanne, Switzerland.
Photodermatol Photoimmunol Photomed. 2018 Sep;34(5):330-337. doi: 10.1111/phpp.12388. Epub 2018 May 31.
BACKGROUND/PURPOSE: Solar ultraviolet radiation (UVR) doses received by individuals are highly influenced by behavioural and environmental factors. This study aimed at quantifying hats' sun protection effectiveness in various exposure conditions, by predicting UVR exposure doses and their anatomical distributions.
A well-defined 3-dimensional head morphology and 4 hat styles (a cap, a helmet, a middle- and a wide-brimmed hat) were added to a previously published model. Midday (12:00-14:00) and daily (08:00-17:00) seasonal UVR doses were estimated at various facial skin zones, with and without hat wear, accounting for each UVR component. Protection effectiveness was calculated by the relative reduction in predicted UVR dose, expressed as a predictive protection factor (PPF).
The unprotected entire face received 2.5 times higher UVR doses during a summer midday compared to a winter midday (3.3 vs 1.3 standard erythema dose [SED]) with highest doses received at the nose (6.1 SED). During a cloudless summer day, the lowest mean UVR dose is received by the entire face protected by a wide-brimmed hat (1.7 SED). No hat reached 100% protection at any facial skin zone (PPF : 76%). Hats' sun protection effectiveness varied highly with environmental conditions and was mainly limited by the high contribution of diffuse UVR, irrespective of hat style. Larger brim sizes afforded greater facial protection than smaller brim sizes except around midday when the sun position is high.
Consideration of diffuse and reflected UVR in sun educational messages could improve sun protection effectiveness.
背景/目的：个体所接受的太阳紫外线辐射（UVR）剂量受行为和环境因素的影响很大。本研究旨在通过预测UVR暴露剂量及其解剖分布，量化帽子在各种暴露条件下的防晒效果。
将明确的三维头部形态和4种帽子款式（一顶帽子、一个头盔、一顶中檐帽和一顶宽檐帽）添加到先前发表的模型中。考虑到每种UVR成分，估计了在有帽和无帽情况下，不同面部皮肤区域的中午（12:00 - 14:00）和每日（08:00 - 17:00）季节性UVR剂量。通过预测UVR剂量的相对降低来计算防护效果，以预测防护因子（PPF）表示。
在夏季中午，未受保护的整个面部接受的UVR剂量是冬季中午的2.5倍（3.3标准红斑剂量[SED]对1.3 SED），鼻子部位接受的剂量最高（6.1 SED）。在无云的夏日，整个面部佩戴宽檐帽时接受的平均UVR剂量最低（1.7 SED）。在任何面部皮肤区域，没有一种帽子能达到100%的防护效果（PPF：76%）。帽子的防晒效果随环境条件变化很大，并且主要受漫射UVR的高贡献率限制，与帽子款式无关。除了太阳位置较高的中午前后，帽檐较大的帽子比帽檐较小的帽子能提供更好的面部防护。
在防晒教育信息中考虑漫射和反射的UVR可以提高防晒效果。
