Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

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.

January 11, 1996

Mr. James A.J. Connell
USA Engineering, Inc.
500 Ellis Avenue
Colwyn, PA 19023

Dear Mr. Connell:

This is in response to your May 26, 1994, letter requesting an interpretation of the process safety management (PSM) of highly hazardous chemicals (HHCs) standard, 29 CFR 1910.119. Process scenarios at work sites and associated questions are noted below. Our corresponding replies follow. Please accept our apology for the delay in responding.

Scenario: Our Client, a multi-plant operator, has in some plants a product used as an alternative "synthetic" fuel. This product fuel is used to fire boilers and industrial furnaces. The synthetic fuel is delivered to the plant in 55 gallon D.O.T. approved drums. The drums enter a drum handling system which involves a volume corresponding to weight which exceeds the threshold quantity of 10,000 pounds (4535.9kg) of flammable liquid (having a flashpoint below 100 degrees F) in one plant area. In essence, this is a fuel compositing operation of various stocks which must meet the contract requirements for fuel value and flashpoint.

Note that the incoming feed stocks are, in general, free of any of the compounds listed in Appendix A of OSHA 1910.119 and in any case the amount present in the most heavily contaminated feed stock would not reach the threshold quantity (TQ) listed. Such compounds are, if found at all, present in trace quantities - perhaps in the parts per million by weight level.

The question of applicability arises at the point where the various source liquids are emptied into the holding tanks. The holding tanks are designed for operation at atmospheric pressure and they are provided with standard breathers. The tanks are provided with agitators to minimize problems of stratification or setting of any solids which may be present.

The tanks are located at a site sufficiently separated from the drum processing area that an incident at the drum unloading operation should not have any impact on the storage tank(s). The transfer of the fuel stock is made via a pipeline which is normally isolated by valves except for those periods of short duration when the transfers are made. Subsequently, the fuel stock is loaded on tank transports for delivery to the user's work site.

Upon arrival at the fuel user's site, the tank transports are pumped into day tanks which are designed to accept direct shipments of "pre-qualified" in-specification fuel stock from multiple sources. These day tanks are of low pressure design for operation at atmospheric pressure and they are provided with standard breathers. They are also provided with agitators to reduce stratification and to disperse and suspend any solids present. The contents of these day tanks are analyzed to certify that the material meets any permit restrictions as well as the fuel value, quality and composition stipulated in the contract with the fuel user. The fuel is pumped from the day tanks to bulk fuel storage tanks of a similar design but larger volume. These feed tanks are used to supply the fuel to the burner assemblies at each boiler or furnace.

Question 1: Would the atmospheric tanks system at the drum handing/unloading facility be classified as a covered process?

Reply: The 55 gallon drums of flammable liquids, the drum handing system, the holding tanks where the flammable liquids are mixed, the storage tanks and interconnecting piping are considered a single process. (See the definition of "process" under 1910.119(b)). Please note that a process which contains a threshold quantity (TQ) or greater amounts; that is, 10,000 pounds (4535 kg) of flammable liquids at any one point in time would be covered by the PSM standards with exceptions.

Also, the aggregate amount of flammable liquids in the process is the basis for determining TQ. As such, the aforementioned process is covered by the PSM standard. Since the process involves the activities of handling (in addition to mixing or blending) and on-site movement as well as storage in atmospheric tanks or transfer of flammable liquids which are kept below their normal boiling point without benefit of chilling or refrigeration, the exception under paragraph 1910.119(a)(1)(ii)(B) does not apply.

Question 2: Would the process which includes day tanks and interconnected bulk fuel storage tanks at the fuel user's work site be classified as a covered process?

Reply: There is insufficient scenario information to determine whether this process would be covered by the PSM standard. The following clarification is intended to assist you in this determination.

The process you described supplies fuel (flammable liquid), presumably by interconnected piping, to boilers and furnaces. Under the paragraph 1910.119(b) definition of "process", vessels interconnected to other vessels are considered a single process. When this single process involves stored flammable liquids in activities including use, handling, on-site movement or manufacturing, the exception under paragraph 1910.119(a)(1)(ii)(B) would not apply. Unless one of the other exceptions, for example, hydrocarbon fuels used solely for workplace consumption as a fuel, applies, the single process you described would be covered by the PSM standard. Also, this single process would be covered when a boiler or furnace is part of a process containing another HHC covered by the PSM standard.

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

Sincerely,



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




May 26, 1994

Mr. H. Berrien Zettler, Director
Directorate of Compliance Programs
Department of Labor - OSHA
Frances Perkins Building
200 Constitution Avenue, N.W.
Room N 3468
Washington, D.C. 20210

Dear Mr. Zettler:

Our company has been offering engineering services to small and medium sized chemical companies to assist them in complying with the general mandates - Federal, State and/or local - governing the safe and proper operations of their plants.

We are, at present, working with a client on the development of the Process Safety Management Program as required by OSHA 1910.119 and we have found a situation which is, to us, ambiguous relative the definition of a "covered process". We are therefore asking for an interpretation of the situation.

Our client, a multi-plant operator, has in some plants a product used as an alternative "synthetic" fuel. This product fuel is used to fire boilers and industrial furnaces. The generation of the synthetic fuel starts with the receipt or collection of various combustible waste liquid streams from several sources. The selection and acceptance of the streams is a closely controlled procedure which depends on a "pre-qualification" program. This program uses complete analyses of any proposed stream to establish its fuel value and, more importantly, its chemical composition to establish the levels of toxic of otherwise hazardous compounds which may be encountered. Any such compounds present in concentrations above the allowable levels results in the rejection of the material due to failure to satisfy the pre-qualification conditions and the stream will not be given clearance for shipment to the plant.

When the program permits the acceptance of the stream it is delivered to the plant in 55 gallon D.O.T. approved drums. The drums enter a drum handling system and it is our client's belief that this system is a "covered process" since it involves a volume which represents a mass exceeding the stipulated maximum of 10,000 pounds of liquid (having a flash point below 100 degrees F) in one plant area. All drum emptying operations are carried out in protected (sprinklered) areas isolated by appropriately rated fire walls. The drum contents are composited in storage tanks which will exceed the 10,000 pound threshold level. In essence, this is a fuel compositing operation of various stocks which must meet the contract requirements for fuel value and flash point.

Note that the incoming feed stocks are, in general, free of any of the compounds listed in Appendix A of OSHA 1910.119 and in any case the amount present in the most heavily contaminated feed stock would not reach the threshold quantity (TQ) listed. Such compounds are, if found at all, present in trace quantities - perhaps in the parts per million by weight level.

The question of applicability arises at the point where the various source liquids are emptied into the holding tanks. The holding tanks are designed for operation at atmospheric pressure and they are provided with standard breathers. The tanks are provided with agitators to minimize problems of stratification or setting of any solids which may be present. The tanks are located at a site sufficiently separated from the drum processing area that an incident at the drum unloading operation should not have any impact on the storage tank(s). The transfer of the fuel stock is made via a pipeline which is normally isolated by valves except for those periods of short duration when the transfers are made.

The fuel is then sampled and analyzed to certify that it is acceptable for transport (D.O.T.) and that it meets the fuel values stipulated by the contract. Upon completion of the documentation, the material in the holding tank is released for delivery to the users.

Upon arrival at the fuel user's site, the tank transports are pumped into day tanks which are designed to accept direct shipments of "pre-qualified" in-specification fuel stock from multiple sources. These day tanks are of low pressure design for operation at atmospheric pressure and they are provided with standard breathers. They are also provided with agitators to reduce stratification and to disperse and suspend any solids present.

The contents of these day tanks are analyzed to certify that the material meets any permit restrictions as well as the fuel value, quality and composition stipulated in the contract with the fuel user.

The fuel is pumped from the day tanks to bulk fuel storage tanks of a similar design but larger volume. These feed tanks are used to supply the fuel to the burner assemblies at each boiler or furnace.

Our specific questions are: 1. Would the atmospheric tank system at the drum handling/unloading facility be classified as a "covered process"? 2. Would the atmospheric day tanks at the fuel user's facility be classified as a "covered process"? 3. Would the atmospheric bulk fuel storage tanks at the fuel user's facility be classified as a "covered process"?

Thank you for your consideration and cooperation in this matter.

Sincerely Yours,



James A.J. Connell, P.E.