What is the main purpose of OSHA (Occupational Saftey And Health Administration? (USA) Occupational Health & Saftey (Canada) The main purpose if OSHA or OH&S is to assure safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education and assistance. Why are they Not Protecting the Public Body from being Forced to Wear Face Masks? Right on the face mask box label, the label tells you the face mask will not protect you! I beg you Please Read the face mask box.