Source: https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=26000
Timestamp: 2014-03-10 05:00:21
Document Index: 406482291

Matched Legal Cases: ['§1910', '§1910', '§1910', '§1910', '§1910', '§1910', '§1910', '§1910', '§1910']

12/26/2007 - Clarification of requirements for storage and use of flammable and/or combustible liquids.
1910.106; 1910.106(b); 1910.106(b)(4)(ii); 1910.106(e); 1910.106(e)(2)(ii)(c); 1910.106(e)(2)(iii); 1910.106(e)(2)(iv)(d); ; 1910.106(e)(3)(v)(a); 1910.106(e)(3)(vi); 1910.106(h)(4)(iii)(a); 1910.119(e)(1); 1910.1000
Question 2:	§1910.106(e)(2)(iii) in part states that "Adequate natural or mechanical ventilation shall be provided." Does the adequate ventilation in this paragraph mean the ventilation rate of 1 cubic foot per square foot of solid floor area, as defined in §1910.106(e)(3)(v)?
Question 3:	Does §1910.106(e)(2)(iii) require introduction of fresh air similar to provisions contained in §1910.106(e)(3)(v)(a)?
Question 4:	Does §1910.106(b) apply to storage of Class IB or IC flammable liquids in quantities less than 120 gallons?
Response 5: There is insufficient information provided to determine if the plant is an industrial (covered under 1910.106 (e)) or a processing plant (covered under 1910.106(h)). Further, if this question were related to an industrial plant, due to the lack of information, we cannot determine which of the industrial plant requirements would apply ((e)(2)  Incidental storage or (e)(3)  Unit Physical Operations). However, we have provided information below, which may assist you in determining how to apply the various standards in question.
a) through a closed piping; or b) from safety cans; or
Question 6:	Are vents and emergency relief vents on portable tanks containing Class 1B and 1C flammable liquids required to be piped outside the building?
Question 7:	Does §1910.106(e)(2)(ii)(c) and §1910.106(h)(4)(i)(b) apply to processing tanks, such as a buffer mix tank (not a storage tank)? If not, is there a requirement for the processing tank to vent outside the building?
Response 7: OSHA considers that buffer mix tank operations  where a Class IB liquid is poured into buffer mix tank in making a Class IC liquid  as process tanks, and not storage tanks. OSHA standards §1910.106(e)(2)(ii)(c) and §1910.106(h)(4)(i)(b) apply to storage tanks and not to process tanks, such as buffer mix tanks, and OSHA's 1910.106 standards do not have provisions requiring processing tanks such as mix tanks containing Class I liquids to vent outside the building. This assumes these tanks are not pressure vessels, i.e., designed to operate at pressures greater than 15 psig. If these tanks are pressure vessels, good engineering practice according to the ASME (Section VIII, UG-134(g) of the ASME Boiler and Pressure Vessel Code) requires in part, "Discharge lines from pressure-relieving safety devices shall . . . lead to a safe place of discharge [emphasis added]."
Similar to our Response 6, the employer is responsible for controlling the serious hazard of relieving/venting a process tank into a confined area such as a room/building. If a process tank is part of a PSM-covered process, then the employer must control the hazard as stated in Response 6. If the process tank is not part of a PSM-covered process, and this hazard exists, then OSHA may enforce the General Duty Clause of the Act. Note that NFPA 30  2008, Paragraph 17.11 requires that exhaust ventilation be discharged to a safe location outside of buildings. This provision applies to all types of operations that use and handle flammable and combustible liquids. Additionally, section 17.15.3 of NFPA 30-2008, in part, states that "The extent of fire prevention and control that is provided shall be determined by means of an engineering evaluation of the operation and application of sound fire protection and process engineering principles." OSHA may find that process tanks that do not comply with these requirements violate the General Duty Clause.
Question 8:	A prevalent belief is that if there is adequate ventilation, processing tank vents do not need to go outside the building. This is desirable in the pharmaceutical industry, because of the concern about the cleanliness of air that may enter the vessel through the vent. Is there a code basis for this belief?
Question 9:	Is it acceptable for any tank containing Class I flammable liquids to vent inside the building? If so, what kind of local exhaust pick-up and/or LEL monitoring would be required?
Thank you for your interest in occupational safety and health. We hope you find this information helpful. 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 guid