Facial warming and tinted helmet visors

Tinted helmet visors have found applications in several areas as a means of reducing visual strain under bright conditions. For motorcyclists, new technologies which can rapidly change the level of tinting promise to make such visors more accessible, which is necessary to avoid safety risks. For these users, it is often important to minimize the heat load on the body. We studied the changes in the heat load on the face as a function of motorcycle helmet visor configuration (normal and tinted) using a thermal head manikin and (n=8n=8) human subjects. Good agreement was found between the measured and perceived heat load, and this load was greatly reduced for moderate tinting levels. The optical transmission properties of the visor configurations largely explain the results. Our results suggest that visors optimized for infrared rejection would likely be perceived as an improvement.Relevance to industryThe production of motorcycle and other tinted helmet visors could be aimed at multiple benefits, viz, visual and thermal protection and comfort. The role of comfort in the use of such products is important for industry, as well as knowledge of how to assess such effects.