Standard Interpretations - Table of Contents|
| Standard Number:||1926.350; 1926.800|
May 5, 1992
Mr. George Brown, P.E. Director,
Dear Mr. Brown:
This is in response to your January 30 letter requesting an interpretation of Occupational Safety and Health Administration (OSHA) requirements addressing the transportation of compressed gas cylinders. I apologize for the delay in responding to you.
As you know, the present interpretation of paragraphs 1926.350(a)(4) and (9) prohibits the transporting of compressed gas cylinders in the horizontal position by powered vehicle at construction sites. However, considering the unique hazards associated with underground transportation of gas cylinders, your proposed method of securing and storing the cylinders while transported underground, and that current Department of Transportation regulations allow this practice under limited conditions, OSHA would consider your described method of transporting compressed gas cylinders as a de minimis situation at your San Pedro Creek and San Antonio River tunnel and shaft project in San Antonio, Texas if conducted under the following conditions:
1. Oxygen cylinders are secured against movement in all directions in a rack secured to the segment car.
2. Acetylene cylinders are secured against movement in all directions in a rack secured to the segment car. The tops of all acetylene cylinders are elevated so that the cylinders are inclined at an angle of not less than 30 degrees from horizontal (to protect against loss of acetone).
If we can be of any further assistance please contact Mr. Roy F. Gurnham or Mr. Dale Cavanaugh of my staff in the Office of Construction and Maritime Compliance Assistance at (202) 523-8136.
cc: Paul C. Zink John Wheeler
Mr. Roger Clark,
Subject: Transportation of compressed gas cylinders in underground (tunnel) construction.
The Obayashi Corporation is a General Engineering Contractor engaged in heavy construction, primarily tunnel construction.
We are presently engaged in a large tunneling project for a US Government Agency and have had some difficulty with an interpretation of The Act and specifically CFR 1926.350(a)(4) and (a)(9).
We seek immediate relief by requesting an interpretation of the wording contained in (a)(9). The Standards and our comments are listed below.
29 CFR 1926.350(a)
(4) "When cylinders are transported by powered vehicles, they shall be secured in a vertical position".
29 CFR 1926.350(a)
(9) "Compressed gas cylinders shall be secured in an upright position at all times except, if necessary for short periods of time while cylinders are actually being hoisted or carried". (emphasis added)
29 CFR 1926.350(a)(4) appears to address the transporting of cylinders unique to the gas supplier industry and appears to assume that "powered vehicles" means trucks or other above ground transporting systems. Transportation in tunnels is usually by rail systems such as our present project uses.
29 CFR 1926.350(a)(9) seems to allow the "carrying" of cylinders in the horizontal position for short periods of time. However, FED OSHA has interpreted "carrying" as meaning, "carrying by a person".(emphasis added)
The "carrying" of cylinders by a person, is contrary to a safe way to handle them and it is not allowed in our operations. Cylinders are moved by hand by rolling them on the bottom of the cylinders while holding and balancing them. CFR 1926.350(a)(3).
Webster's dictionary definition of "carrying" does not limit this action to one involving only personal handling. By limiting the definition, it precludes any mechanical means of "carrying". By re-defining "carrying", the rule as written in CFR 29 1926.350(a)(9) would allow mechanical means to be used.
In tunnel construction, it is conceivable that the size of the tunnel, the height of the rail car above the invert and the ventilation line at the crown of the tunnel, would not allow the cylinders to be transported safely in a vertical position.
Additionally, the possibility of de-railment exists and the cylinders would be subject to greater moment-arm forces if they are in a vertical position.
Transporting of cylinders from the shaft or portal to supply the tunnel involves a short period of time and can be more safely accomplished by placing the cylinders in a substantial horizontal rack that is firmly fixed to the conveyance and securely anchoring them to preclude any movement. The rack should be constructed so physical protection is afforded to the vulnerable cap end of the cylinders.
The other concern is that the acetylene cylinders would present an additional hazard due to the acetone in the cylinders which could migrate to the valve end and present a fire and explosion hazard if used in that position or if insufficient time before use in the vertical position occurs. This hazard exits and is already controlled by proper training and education and by prohibiting the use of any compressed gas cylinders in a horizontal position.
Since we are seeking immediate relief, the re-defining of the word "carried" would provide it. However, a long term solution would be preferred utilizing CFR 29 1926.800.
A suggested format for covering the transportation of compressed gas cylinders in underground (tunnel) construction is as follows:
CFR 1926.800 Underground construction
(m) Fire prevention and control
(add the following)
(iii) When compressed gas cylinders are transported underground, they shall be secured in the horizontal configuration in a substantial rack that will prevent rolling and movement during transport and provide protection to the valve ends of the cylinders.
(iv) Cylinders shall be transported without regulators attached and with the valve protection caps in place.
(v) After the cylinders arrive at their location for use or storage, they shall be immediately removed from the conveyance and rack, placed in a storage rack in the vertical position and securely restrained to prevent tipping or falling over.
(vi) All other applicable provisions of CFR 1926.350 shall be adhered to.
Thank you for your attention to the matter and expecting to have a reply in the immediate future, I remain,
Serial Letter OX-289
Obayashi Corporation is the primary contractor for the construction of the San Pedro Creek and San Antonio River Tunnel and Shaft Project in San Antonio, Texas. We are presently tunnelling a 16,080 feet tunnel, 27 feet in diameter at a depth of 150 feet.
Pursuant to 1905.10 Subpart B Variance, and other relief under Section 6(b) (6)(A) of the Act. Obayashi Corporation submits this application for Variance of, 29 CFR 1926.350(a)(4) which states, " When cylinders are transported by powered vehicles, they shall be secured in a vertical position."
Traveling from the portal (entry) of the tunnel to the heading (working area) presents several problems due to the distance required for travel. Our main means of moving materials, equipment, personnel and supplies into the tunnel and to the working face, then back to the surface is by track haulage. This consists of a railroad with underground cars and a diesel powered locomotive.
A study reported in MSHA training manual for underground mining, stated that accidents associated with track haulage of materials accounted for nearly one-fifth of all underground mining accidents. Track haulage accidents can be grouped into four categories; 1) collisions between vehicles, 2) cars colliding with people, 3) derailment, and 4) runaway vehicles. These types of accidents are typical and are peculiar to underground operations.
Obayashi Corporation contends that due to the above circumstances, horizontal transportation of gas cylinders is at least as effective, from a safety standpoint, as vertical transportation. Since provisions of 1926.350 are not discussed in the standards of Subpart S 1926.800, we request the following variances as an alternate means of complying with 29 CFR 1926.350(a)(4); and submit a drawing depicting the method by which the below will be implemented:
1. When compressed gas cylinders are transported, they will be secured in horizontal configuration on a flat car that would prevent rolling and movement during transportation.
2. After the compressed gas cylinders arrive at their location for use or storage, they would be immediately removed from the flat car, placed in a chained rack, or otherwise positively secured in an upright position to guard against tipping over.
3. Compressed gas cylinders will never be transported with the regulators attached and without the valve protection caps in place.
4. Adhere to all other provisions of 29 CFR 1926.350.
5. Give notice to all affected employees the terms of this request and their right to petition the Assistant Secretary for a hearing.
If you need further information, please contact this office.
Very truly yours,
Standard Interpretations - Table of Contents|