Amazon.com description: Product Description: This publication has been prepared by the Occupational Safety and Health Administration (OSHA) to help dry cleaning establishments reduce employee exposures to perchloroethylene (also known as perc, tetrachloroethylene, C2Cl4 or Cl2C=CCl2). The dry cleaning industry has improved the control of perchloroethylene in recent years, and modern dry cleaning equipment involves much lower exposures than older style equipment. However, there is still a need to reduce employee exposure to the chemical to reduce any possible health effects that could result from long-term exposure to the chemical. Many dry cleaning employers have found that equipment design, preventive maintenance, control of leaks in equipment, proper ventilation, and good work practices can reduce perc exposure to workers, reduce costs by recovering perc for reuse, help create a cleaner environment, and help comply with federal and state environmental regulations.