1910.106(b)(4)(iv): Tank openings other than vents
Key takeaways
- 1910.106(b)(4)(iv) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart H).
- OSHA cited it 2 times in the last 3 years, in 2 inspections, with $0 in current penalties.
- Related part: 1910.106(b) Tank storage (99 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1910.106(b)(4)(iv) ("Tank openings other than vents") is one requirement inside 1910.106 Flammable liquids, an OSHA general industry standard (Part 1910, Subpart H). The official text below is copied word for word from the Electronic Code of Federal Regulations (eCFR). The numbers, injury cases and training on this page show how OSHA enforces it on real job sites.
Official text
(iv) Tank openings other than vents. 2 citations
(a) Connections for all tank openings shall be vapor or liquidtight. Vents are covered in subdivision (ii) of this subparagraph.
(b) Each connection to a tank inside of buildings through which liquid can normally flow shall be provided with an internal or an external valve located as close as practical to the shell of the tank. Such valves, when external, and their connections to the tank shall be of steel except when the chemical characteristics of the liquid stored are incompatible with steel. When materials other than steel are necessary, they shall be suitable for the pressures, structural stresses, and temperatures involved, including fire exposures.
(c) Flammable liquid tanks located inside of buildings, except in one-story buildings designed and protected for flammable liquid storage, shall be provided with an automatic-closing heat-actuated valve on each withdrawal connection below the liquid level, except for connections used for emergency disposal, to prevent continued flow in the event of fire in the vicinity of the tank. This function may be incorporated in the valve required in (b) of this subdivision, and if a separate valve, shall be located adjacent to the valve required in (b) of this subdivision.
(d) Openings for manual gaging, if independent of the fill pipe (see (f) of this subdivision), shall be provided with a vaportight cap or cover. Each such opening shall be protected against liquid overflow and possible vapor release by means of a spring loaded check valve or other approved device.
(e) For Category 2 flammable liquids and Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), other than crude oils, gasoline, and asphalts, the fill pipe shall be so designed and installed as to minimize the possibility of generating static electricity by terminating within 6 inches of the bottom of the tank.
(f) The fill pipe inside of the tank shall be installed to avoid excessive vibration of the pipe.
(g) The inlet of the fill pipe shall be located outside of buildings at a location free from any source of ignition and not less than 5 feet away from any building opening. The inlet of the fill pipe shall be closed and liquidtight when not in use. The fill connection shall be properly identified.
(h) Tanks inside buildings shall be equipped with a device, or other means shall be provided, to prevent overflow into the building.
Source: eCFR, text current as of 2026-10-15. Read all of 1910.106.
Where and how often it was cited
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Related parts of this rule
- 1910.106(b) Tank storage 99 citations
- 1910.106(b)(6) Sources of ignition 59 citations
- 1910.106(b)(2) Installation of outside aboveground tanks 23 citations
- 1910.106(b)(2)(vii) Drainage, dikes, and walls for aboveground tanks— 13 citations
- 1910.106(b)(4) Installation of tanks inside of buildings 6 citations
- 1910.106(b)(2)(ii) Spacing (shell-to-shell) between aboveground tanks 5 citations
- 1910.106(b)(5) Supports, foundations, and anchorage for all tank locations 5 citations
- 1910.106(b)(1) Design and construction of tanks 4 citations
- 1910.106(b)(4)(ii) Vents 2 citations
- 1910.106(b)(7) Testing 2 citations
- 1910.106(b)(1)(i) Materials 1 citations
- 1910.106(b)(5)(ii) Fire resistance
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Sources
- 29 CFR 1910.106 (eCFR), text current as of 2026-10-15
- U.S. Department of Labor enforcement data: OSHA inspections, citations and accident records, copied nightly; data as of 2026-10-21
3-year window. Federal OSHA only; state-plan rules are not counted. Plain-language text is a summary, not legal advice; the official text controls. Black Belt Safety is not part of OSHA or the Department of Labor.