fastfacts August 2006

Volume I, Number 8 advancing safety, health, and workplace rights in the legislative branch 

Pressurized Cylinders


The Loaded Weapon in Your Workplace 

If you had a potentially deadly 

weapon in your workplace, you’d probably 

keep a close eye on it. Yet, during their 

biennial health and safety inspections,

Office of Compliance (OOC) inspectors 

repeatedly find hazardous pressurized cylinders unsecured and full of gases. 

Potential Dangers of a Pressurized 

Cylinder 

Pressurized cylinders, used to store 

various flammable and nonflammable 

gases, are likely to fall over if left unsecured, such as those in Figure 1. Such a 

fall could cause damage to the cylinder’s 

Figure 2: Properly stored cylinders 

valve or the cylinder itself, resulting in a gas leak.

A rapid loss of pressure can 

turn a cylinder into an unguided 

missile powerful enough to break 

through a concrete wall. If the 

cylinder’s gas is flammable, that 

power may also be accompanied 

by a fire or explosion.

Pressurized cylinders can 

result in some of the most serious violations cited by the OOC.

In all its inspections, the OOC 

assigns a Risk Assessment Code

(RAC) on a scale of 1 (most 

serious) to 4 (least serious) to 

each violation to help explain 

the severity of the hazard. OOC 

inspectors assign a RAC 1 to all 

unsecured cylinders with a flammable gas such as acetylene, as they 

carry a probable risk of catastrophic 

injury, physical damage, and/or death 

if the cylinder falls or is damaged and gas 

leaks. Inspectors assign a RAC 2 to unsecured cylinders that contain nonflammable 

gasses such as carbon dioxide or nitrogen,

as there is still a probable risk of critical injury and/or physical damage if the 

cylinder were to be damaged and become 

a missile. 

Properly Caring for a Pressurized 

Cylinder 

To avoid this potential loss of 

property—and even human life—chain 

or secure all pressurized cylinders to keep 

them from falling. (29 CFR 1926.350 

(a)(7) and 1910.253(b)(2)) 

www.compliance.gov 

Even if the cylinder is properly 

stored, protect its valve like it still may fall:

keep the safety cap on when the cylinder is 

not in use, as seen in Figure 2.

To prevent misuse of certain gases,

properly label all cylinders to identify 

the type of gas contained inside. Do not 

remove or deface these labels in any way.

Additionally, you are required to 

inspect, hydrostatically test, and pressure test pressurized steel cylinders every 

five years. Test aluminum cylinders every 

twelve years. Note that the supplier typically conducts these tests when the cylinders are refilled. 

Never store a pressurized cylinder 

outside or in any other place where it may 

rust, as this weakens the cylinder wall.

A rusted cylinder can leak gas or even 

rupture, causing an explosion or sudden 

Figure 1: Improperly stored cylinders 
Fiure 3: Result of an improperly stored cylinder.

Image and details courtesy of the U.S. Department of Labor, Mine and Health 

Safety Division 

rocketing. Cylinders stored outside can also 

be subjected to extreme temperatures, which 

can cause damage. To prevent a rapid rise in 

internal pressure that can cause the cylinder 

wall to fail, acetylene cylinders should not 

be stored in areas where the temperature can 

exceed 125 degrees Fahrenheit. 

What’s the Worst That Could Happen? 

Figure 3 at right illustrates the potential 

danger of an improperly stored pressurized 

cylinder.

The driver of this vehicle left an acetylene cylinder with a slightly opened valve in 

the back seat of his vehicle over a weekend. 

When he opened the door on Monday morning, the result was the explosion pictured 

here. The leaking acetylene could have been 

ignited by any number of seemingly harmless 

factors, including the use of a mobile phone,

the lighting of a cigarette, or the activation of 

the automatic door control or interior lights.

The vehicle’s driver sustained damage to 

his eardrums and some facial scarring, but the 

consequences of his mistake could have been 

far more serious. 

fast stats


• The United States Department of Labor, Bureau of Labor Statistics, reported that pressurized containers 

caused 5,160 injuries involving days away from work and 17 deaths in 2004. 

• The Office of Compliance 108th Congressional Biennial Safety and Health Inspections found 17 instances 

of unsecured compressed gas cylinders. 

• The Code of Federal Regulations (CFR) requires all pressurized cylinders to be secured properly and 

fitted with safety caps when not in use. (29 CFR 1910.253(b)(2)(ii) and (iv) and 1926.350(a)(6) and (7)) 

• The National Fire Protection Association (NFPA) requires that all flammable gasses be stored a minimum 

of 20 feet from oxygen or be separated from oxygen by a fire-resistive partition. (NFPA 51) 

If you spot a safety hazard in your legislative branch 

workplace, contact the Office of Compliance to report it: The Office of Compliance advances safety, health, and 

Room LA 200, John Adams Building workplace rights in the U.S. Congress and the Legislative Branch. Established as an independent agency 

110 Second Street, SE by the Congressional Accountability Act of 1995,

Washington, DC 20540 the Office educates employees and employing offices Rachel Berg Scherer t/ 202-724-9250; tdd/ 202-426-1912; f/ 202-426-1913 about their rights and responsibilities under the Act,

Editor provides an impartial dispute resolution process, and 

Victor Ontiveros Recorded Information Line/ 202-724-9260 investigates and remedies violations of the Act. 

Author www.compliance.gov 

This information does not constitute advice or an official ruling of the Office of Compliance or the Board of Directors and is intended for educational 

purposes only. For further information, please refer to the Congressional Accountability Act (2 U.S.C 1301 et seq.) and the regulations issued by the 

Board, or you may contact the Office of Compliance.