Exposure of car guards to solar ultraviolet radiation during summer and winter

Abstract

Introduction: Outdoor workers such as car guards are at an increased risk of excessive exposure to solar UVR due to long hours working in the absence of a shade structure and personal protective equipment. Cumulative exposure increases the risk of developing adverse health effects such as skin cancer, a Group 1 carcinogen, caused by the sun. The aim of this study was to quantify personal solar ultraviolet radiation exposure of car guards during summer and winter. Methods: Car guards’ upper arm exposure to solar UVR was measured at the shopping centre for 10 days during summer (20 February 2019 – 05 March 2019) and winter (22 July 2019 – 02 August 2019) respectively by means of Genesis-UV personal electronic dosimeters. The Genesis-UV dosimeter was placed on the upper arm of the participant using an adjustable strap. Results from these measurements were used to estimate solar UVR exposure on various anatomical areas. In addition, hand-held UV monitors were used to determine the levels of ambient solar UVR reaching a flat, horizontal surface and heat stress levels were also determined during the sampling period by means of the QUESTempº32/34. The QUESTempº32/34 was used to evaluate environmental conditions such as temperature and relative humidity influencing the intensity of solar UVR received by workers. Results: The average exposure of car guards to solar UVR was 11.50 SED during summer and 5.47 SED during winter. Exposure as a percentage of ambient UVR during summer was 30.79%, whilst that of winter was 26.61%. The exposure of car guards on the upper arm was below that of other anatomical areas, even though values were in excess of the threshold limit value (TLV). Heat stress measurements obtained during summer indicated a WBGTo ranging between 22.60 – 30.94, and that of winter ranged between 8.32 – 20.32. Conclusion: The high exposure of car guards to solar UVR is a concern because while being independent contractors, it is difficult for them to implement the necessary protective measures. The security industry together with companies manufacturing sunscreens and protective clothing (sun hats and long-sleeved shirts) should form a collaboration with each other promoting the effective use of protective measures among car guards.