From the National Safety Council
When a boss calls an employee a “competent person,” it is not necessarily a compliment – it is a legal obligation.
A competent person is an employee who is able to recognize hazards associated with a particular task, and has the ability to mitigate those hazards. Many OSHA construction standards require someone onsite – such as a foreman, supervisor or other employee – to be designated as a competent person.
However, OSHA does not have a specific standard regarding a competent person, which has led to some confusion. Read the article here