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.

August 27, 1982

Mr. William Jones
Environmental Engineer
Halliburton Services
Department of Government Regulations
Drawer 1431
Duncan, Oklahoma 73533

Dear Mr. Jones:

Thank you for your letter of July 26, 1982, requesting an interpretation of certain 29 CFR 1910.106 standards for your operation of indoor tank storage and handling of flammable and combustible liquids. This also confirms a telephone discussion of the subject matter with a member of my staff, Mr. Peter Wasko, in which you pointed out that liquid is added in very small amounts to mix with the acid in your 500-4,000 gallons-capacity acid tanks vehicles at the loading dock located up to 25 feet from the building.

Your operation, as indicated above, appears to be a unit physical operation covered by 29 CFR 1910.106(e)(1)(i)(b) and (3) (copies enclosed). Note that 1910.106(e)(3)(vi) requires that storage, transfer, and handling of liquid be according to 1910.106(h)(4) and that 1910.106(h)(4)(i)(b) and (i)(c) (copy enclosed) permit storage tanks inside buildings according to 1910.106(b), where 1910.106(b)(4) would apply (copy enclosed). Hence, the relevant requirements of 29 CFR 1910.106(e), as indicated in this paragraph, could apply to your indoors storage tanks.

In regards to the applicability of 29 CFR 1910.106(f), it appears that the facility concerning you is a unit physical operation facility and not a bulk plant. Hence, 29 CFR 1910.106(f) would not apply.

In regards to the applicability of 29 CFR 1910.106(b)(4)(i), the more specific standards where they exist, as in 29 CFR 1910.106(h)(4)(i)(b) and (i)(c), would take precedence over any more general relevant standard.

Should you have any further questions, please do not hesitate to contact Mr. Peter Wasko, of this office at 202/523-8124.


Patrick R. Tyson
Director, Federal Compliance
and State Programs