Health and safety at work has been seen as an issue of increasing importance during the 20th and 21st centuries. During the industrial revolution and the 18th and 19th centuries, limited union strength and a lack of regulation made workplaces extremely dangerous environments. Factories with newly designed equipment, with numerous unprotected moving parts could easily seriously injure or kill an employee. Without adequate legislation or union support, those injured in this way would often not be compensated. However as trade union membership grew both in size and influence, health and safety changes were implemented and ensured an improved working environment.