First reason   Federal regulation requires that PPE training be administered by the employer

Specifically, in section (f) of 29 CFR 1910.132:


The employer shall provide training to each employee who is required by this section to use PPE. Each such employee shall be trained to know at least the following:
(i) When PPE is necessary;   aa1.gif (4518 bytes)
(ii) What PPE is necessary;  aa2.gif (4518 bytes)
(iii) How to properly don, doff, adjust, and wear PPE;aa3.gif (4518 bytes)
(iv) The limitations of the PPE; and,aa4.gif (4518 bytes)
(v) The proper care, maintenance, useful life and disposal of the PPE.  aa5.gif (4518 bytes)

and so on.....  points (2) and further are below on this page.  The main point here is that it's required by law and we have to do it, and we have to do it the way they say we have to do it.

Second reason -- There's good evidence to support the claim that if people read/review the essentials of personal protective equipment use, the occurrence of occupational illnesses, injuries, and accidents will be minimized. 


   ...remainder of the PPE standard general requirements, if you're interested:


Each affected employee shall demonstrate an understanding of the training specified in paragraph (f)(1) of this section, and the ability to use PPE properly, before being allowed to perform work requiring the use of PPE.


When the employer has reason to believe that any affected employee who has already been trained does not have the understanding and skill required by paragraph (f)(2) of this section, the employer shall retrain each such employee.  Circumstances where retraining is required include, but are not limited to, situations where:
(i) Changes in the workplace render previous training obsolete; or
(ii) Changes in the types of PPE to be used render previous training obsolete; or
(iii) Inadequacies in an affected employee's knowledge or use of assigned PPE indicate that the employee has not retained the requisite understanding or skill.


The employer shall verify that each affected employee has received and understood the required training through a written certification that contains the name of each employee trained, the date(s) of training, and that identifies the subject of the certification.