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Updated: Mar 6, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Distribution of Facial Exposure to Non-melanoma Biologically Effective UV Irradiance Changes by Rotation Angles
Fang Wang1, Jia Ming Yu2, De Qi Yang2
1School of Public Health, China Medical University, Shenyang 110122, Liaoning, China.
Objective:
To show the distribution of facial exposure to non-melanoma biologically effective UV irradiance changes by rotation angles.
Methods:
This study selected the cheek, nose, and forehead as representative facial sites for UV irradiance measurements, which were performed using a rotating manikin and a spectroradiometer. The measured UV irradiance was weighted using action spectra to calculate the biologically effective UV irradiances that cause non-melanoma (UVBEnon-mel) skin cancer. The biologically effective UV radiant exposure (HBEnon-mel) was calculated by summing the UVBEnon-mel data collected over the exposure period.
Results:
This study revealed the following: (1) the maximum cheek, nose and forehead exposure UVA and UVB irradiance times and solar elevation angles (SEA) differed from those of the ambient UV irradiance and were influenced by the rotation angles; (2) the UV irradiance exposure increased in the following order: cheek < nose < forehead; (3) the distribution of UVBEnon-mel irradiance differed from that of unweighted UV radiation (UVR) and was influenced by the rotation angles and exposure times; and (4) the maximum percentage decreases in the UVBEnon-mel radiant exposure for the cheek, nose and forehead from 0°to 180°were 48.41%, 69.48% and 71.71%, respectively.
Conclusion:
Rotation angles relative to the sun influence the face's exposure to non-melanoma biologically effective UV.
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