Laboratories involve a greater variety of hazards than most workplaces. This e-fact sheet focuses on safety in chemical and biological laboratories in particular. It outlines EU legislation on laboratory safety, particularly as it relates to chemical and biological hazards, and pregnant and young workers. It summarises hazards that the lab worker can encounter and gives examples of serious lab accidents that could have been prevented if proper safety measures had been taken. It concludes with a set of checklists to help workers in laboratories assess possible risks, and to monitor safety processes. The checklists cover: General laboratory safety; Information for workers; Chemical safety; Biological safety; Hygiene; Emergency procedures; Personal Protective Equipment (PPE); Hazardous waste.