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.

May 29, 1998

Mr. Tim Bundy
State of Alaska DOL/OSHA
3301 Eagle Street, Suite 305
P.O. Box 197022
Anchorage, AK 99510-7022

Dear Mr. Bundy:

This is in response to your December 2, 1997 letter requesting interpretation of the Process Safety Management (PSM) Standard, 29 CFR 1910.119. Please accept our apology for the delay in responding. Your scenario and question and our reply follow:

Scenario: The following water treatment plant consists of two 2 million gallon water tanks, a valve/instrument house, and a chlorine building. No workers are stationed at this site. Workers are dispatched from the waste water treatment facility which is about 4 miles away from the water treatment plant. They spend an average of 1.5 man hours per day checking the water treatment plant; an additional 2.5 man hours once a week; and an additional 6.5 hours once a month at the plant.

The chlorine building was built in 1995 and consists of a cylinder room, a scrubber room, an emergency generator room, and a utility/storage room. The cylinder room is equipped with monitors that activate remote alarms and a ventilation system which ducts chlorine gas to the adjoining scrubber tank, which neutralizes the gas. The scrubber system is sized to capture and neutralize a full cylinder. One ton chlorine cylinders are used at the water treatment plant. The cylinder room would remain under negative pressure in the event of a chlorine leak.

There are no conveniences for a permanent presence at this site, such as vending machines or bathroom facilities.

Question: Based on this description, would this site be considered a normally unoccupied remote facility under the PSM regulation?

Reply: The water treatment plant described in the scenario above would be considered a normally unoccupied remote facility which would be excepted from PSM Standard coverage as provided under paragraph 1910.119(a)(2).

We appreciate your interest in employee safety and health. If we can be of further assistance, please contact the Office of Safety Compliance Assistance, Mr. Ronald J. Davies, telephone (202) 219-8031, extension 110.

John B. Miles, Jr., Director
Directorate of Compliance Programs