OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

February 22, 1977

Mr. Lloyd C. Pillsbury
Sales Manager
Tyco Instrument Division
4 Hartwell Place
Lexington, Massachusetts 02173

Dear Mr. Pillsbury:

This is in response to your letter dated January 28, 1977, and confirms a telephone conversation with Harold Gier, Safety Specialist, Division of Occupational Safety Programming, concerning your questions about Subpart O, 29 CFR 1910.217, Mechanical Power Presses.

In the interest of clarity, your questions will be answered in the same sequence as they were listed in your letter.

  1. Yes, presence sensing devices satisfy the general machine guarding requirements when properly installed, used and maintained.
  2. The guidelines that define fail safe operation for presence sensing devices are located in 29 CFR 1910.217(c)(3)(iii) and (5) of the General Industry Standards.
  3. Yes, it is legitimate to bypass presence sensing devices or other guards during set-up, provided that remote initiating means prevents the operator's hand or other part of the body from entering the danger area while the machine is operated.
  4. The general machine guarding requirement applies to all employees, including operators, employees working in the vicinity and employees passing by.

There is no official list of industries targeted by the NEP program, but enclosed is a newsletter containing data pertaining to those industries considered due to their high incidence of injuries. Also enclosed is a copy of OSHA Program Directive #100-52 that you requested.

[This document was edited on 3/9/2004 to strike information that no longer reflects current OSHA policy. OSHA Program Directive #100-52 is superseded and is no longer available.]

Hopefully, this information will be helpful to you. If I may be of any further assistance, please feel free to contact me.


Bert M. Concklin
Acting Assistant
Secretary of Labor