more, leading to an associate degree. After students graduate from a program, they take a state licensing exam, which often consists of a written test, and a practical test of styling or an oral exam. Hairdressers must pay for licenses, and occasionally licenses must be renewed. Some states allow hairdressers to work without obtaining a new license, while others require a new license. About 44% of hairdressers are self-employed, often putting in 40-hour work weeks, and even longer among the self-employed. In 2008, 29% of hairstylists worked part-time, and 14% had variable schedules. As of 2008, people working as hairdressers totaled about 630,700, with a projected increase to 757,700 by 2018. Occupational Health Hazards Like many occupations, hairdressing is associated with potential health hazards stemming from the products workers use on the job as well as the environment they work in. Exposure risks are highly variable throughout the profession due to differences in the physical workspace, such as use of proper ventilation, as well as individual exposures to various chemicals throughout one’s career. Hairdressers encounter a variety of chemicals on the job due to handling products such as shampoos, conditioners, sprays, chemical straighteners, permanent curling agents, bleaching agents, and dyes. While the U.S. Food and Drug Administration does hold certain guidelines over cosmetic products, such as proper labeling and provisions against adulteration, the FDA does not require approval of products prior to being sold to the public. This leaves opportunity for variations in product formulation, which can make occupational exposure evaluation challenging. However, there are certain chemicals that are commonly found in products used in hair salons and have been the subject of various occupational hazard studies. Formaldehyde Formaldehyde is a chemical used in various industries and has been classified by the International Agency for Research on Cancer or IARC as “carcinogenic to humans”. The presence of formaldehyde and methylene glycol, a formaldehyde derivative, have been found in hair smoothing products, such as the Brazilian Blowout. The liquid product is applied to the hair, which is then dried using a blow dryer. Simulation studies as well as observational studies of working salons have shown formaldehyde levels in the air that meet and exceed occupational exposure limits. Variations in observed levels are a function of ventilation used in the workplace as well as the levels of formaldehyde, and its derivatives, in the product itself. Aromatic Amines Aromatic amines are a broad