If you are an employee, then you must ensure that your actions at work do not affect the health and safety of either yourself, co-workers and members of the public
If you are an employer, you must ensure that the health and safety of your employees and others, such as members of the public, is not affected by your working activities
If you are self-employed, then you must ensure that the health and safety of yourself and others, such as members of the public, is not affected by your working activities