March 5, 2008

Mr. Andrew Lewis
Safety Manager
Sierra Nevada Corporation
18635 Jarkey Drive
Hagerstown, Maryland 21742

Dear Mr. Lewis:

Thank you for your July 17 letter to the Occupational Safety and Health Administration (OSHA). Your letter has been referred to OSHA's Directorate of Enforcement Program's (DEP) Office of General Industry Enforcement. Your scenario and question has been restated below for clarity.

Scenario: The access to aircraft fuel cells (tanks) are approximately 12 inches wide but many feet in length. Workers remain outside the tank but have their upper extremities and, on occasion, their head extending into the tank to perform the required tasks. The aircraft fuel tank will be drained of its contents, purged of vapor, and monitored for gases and vapors.

Question: Would these tanks be considered confined spaces¹ as defined by OSHA's Permit-required confined spaces standard, 29 CFR 1910.146.

Reply: If it is possible for the employee to fit his or her entire body within the tanks, then they would be confined spaces under §1910.146. On the other hand, if an employee cannot enter the tanks with his or her entire body due to the size of the tanks' diameters, then the tanks would not be considered confined spaces. An employee may still be injured or killed as a result of some atmospheric hazard within such a tank; however, the permit-required confined spaces standard is not intended to address all locations that pose atmospheric hazards. Please be advised that the procedures to protect workers from atmospheric hazards within these tanks would be required by other OSHA standards, such as Subpart Z of Part 1910 General Industry Standards.

As you may know, the State of Maryland administers its own occupational safety and health program under a plan approved and monitored by Federal OSHA. Under this plan, the Maryland Division of Labor and Industry promulgates and enforces occupational safety and health standards under authority of State law. Maryland's Permit-required Confined Space standard is identical to the Federal. For further information on Maryland's standards, enforcement, and compliance assistance, we suggest that you contact:

J. Ronald DeJuliis, Commissioner
Maryland Division of Labor and Industry
1100 North Eutaw Street, Room 613
Baltimore, Maryland 21201-2206

Telephone: (410) 767-2241, Fax: (410) 767-2986
Website: http://www.dllr.state.md.us/labor/mosh.html

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 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 may consult OSHA's website at http://www.osha.gov If you have any further questions, please feel free to contact the OSHA Office of General Industry Enforcement at (202) 693-1850.

Sincerely,



Richard E. Fairfax, Director
Directorate of Enforcement Programs

¹ Confined space means a space that: (1) is large enough and so configured that an employee can bodily enter and perform assigned work; and (2) has limited or restricted means for entry or exit (for example, tanks, vessels, silos, storage bins, hoppers, vaults, and pits are spaces that may have limited means of entry.); and (3) is not designed for continuous employee occupancy. [ back to text ]