OSHA requires employers to post a OSHA Job Safety and Health: It's The Law poster in every workplace.  It must be placed in a conspicuous place where employees can see it.  OSHA recently released a new version of this poster.  You can order free printed copies at OSHA's safety poster resource page.

If you have a previous version of this poster, you are not required to get a new one.

OSHA Job Safety and Health Poster Downloads

Job Safety and Health - It's The Law - English

Job Safety and Health - It's The Law - Spanish

 

Reference

OSHA Safety Poster Resource Page