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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 can consult OSHA's website at http://www.osha.gov.
March 10, 2004
Mr. David A. Touhey, WSO-CST
Contractors Risk Management, Inc.
Post Office Box 211
Concord, NH 03302-0211\
Re: Will a caution tape or rope perimeter satisfy the requirement in Subpart N, §1926.550(a)(9), for a barricade around a crane's swing radius? Does OSHA require specific protection for cable terminal connectors on portable welders?
Dear Mr. Touhey:
This is in response to your letter dated July 3, 2003, to the Occupational Safety and Health Administration (OSHA). You ask if caution tape or rope will serve as adequate barriers around a crane's swing radius under §1926.550(a)(9). You also ask about what safety requirements under §1926.416 apply for protecting employees working with portable welders from electrocution.
We have paraphrased your questions as follows:
Question 1: Does caution tape attached to a crane, forming a perimeter around the crane's swing radius, meet the barricade requirement under §1926.550(a)(9)?
In 29 CFR Part 1926, Subpart N (Cranes, Derricks, Hoists, Elevators, and Conveyors), §1926.550(a)(9) states:
Accessible areas within the swing radius of the rear of the rotating superstructure of the crane, either permanently or temporarily mounted, shall be barricaded in such a manner as to prevent an employee from being struck or crushed by the crane.
The term "barricade" is not defined in Subpart N. However, that term is defined in other OSHA standards. Although these definitions vary, they typically describe a device that delineates and warns of a boundary that is not to be crossed.1 The following are some examples:
Section 1926.203(a) of Part 1926 Subpart G (Signs, Signals, and Barricades):
. . . an obstruction to deter the passage of persons or vehicles.
Section 1926.960(d) of Part 1926 Subpart V (Power Transmission and Distribution):
a physical obstruction such as tapes, screens, or cones intended to warn and limit access to a hazardous area.
Section 1926.502(f)(1)(iv) of Part 1926 Subpart M (Fall Protection):
A rope, wire, chain, or other barricade . . .
Section 1910.269(x) of Part 1910 Subpart R (Special Industries -- Electric Power Generation, transmission and distribution), and §1910.268(s)(5) of Subpart R (Special Industries - Telecommunications):
A physical obstruction such as tapes, cones, or "A" frame type wood and/or metal structures intended to warn and limit access to a work area.
In each of these examples, the purpose of the "barricade" is to delineate a dangerous area and warn employees not to go beyond a specific point.
Similarly, the purpose of §1926.550(a)(9) is to mark the boundaries of the danger area caused by the crane's swing radius and warn employees to stay out. Since that is a similar purpose to the barricade provisions in Subparts V, M, and R, the use of caution tape would be permissible to meet the barricade requirement in §1926.550(a)(9).2
Question 2: Is it impermissible to use rope as a barricade to meet the requirements of §1926.550(a)(9) because it would pose a strangulation hazard?
Although we cannot exclude such a possibility, we are unaware of a scenario in which it would be reasonably foreseeable that an employee would be strangled by a warning rope used to delineate a swing radius hazard.
Question 3: There are construction employees who work with portable welders (under 600 volts) that do not have insulating protection devices covering the lug connections of the cable to the welder. Does OSHA require these connectors to be covered when the welder is in use?
Section 1926.403(a) in Subpart K (Electrical) states that:
All electrical conductors and equipment shall be approved.
Section 1926.403(i)(2)(i) states:
Except as required or permitted elsewhere in this subpart, live parts of electric equipment operating at 50 volts or more shall be guarded against accidental contact by cabinets, or other forms of enclosures… [Emphasis added.]
Welders operating at or above 50 volts
On many older electric welders, the welding cable was connected to the welding terminal via a metal lug connector. This exposed part presents a potential hazard if an employee were to come into accidental contact. Under §1926.403(i)(2)(i), since the lug connector is an exposed, live part, if the welding terminal operates at 50 volts or more, the lug connector must be guarded.
Welders operating below 50 volts
Under §1926.403(a), all electrical conductors and equipment must be "approved." The standard defines approved as "acceptable." With regard to your equipment, the means by which these connectors are insulated must be "accepted, or certified, or listed, or labeled, or otherwise determined to be safe by a qualified testing laboratory capable of determining the suitability of materials and equipment for installation and use in accordance with this standard," §1926.449.
There is no construction standard that requires an insulating cover for these connectors (on this category of welder) when the operating voltage is below 50 volts.3 In addition, from what we have been able to determine in our research of electric welder manufacturers and construction users, it appears that the industry does not recognize the failure to have covers for these connections (on this category of welder) as a hazard in the typical construction use scenario. In their experience, the location of these connections makes it highly unlikely that a worker would be in accidental, simultaneous contact with both an energized portion of the "stinger" side of the circuit and the exposed connections.
If you need additional information, please contact us by fax (202-693-1689) at: U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance. You can also contact us by mail at U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance, Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210, although there will be a delay in our receiving correspondence by mail.
Russell B. Swanson, Director
Directorate of Construction
1In one instance OSHA used the term to mean something that does more than convey a warning to not go into an area. In Table H-21 of §1910.109 (Explosives and blasting agents), the term "artificial barricade" is defined as:
an artificial mound or revetted wall of earth of a minimum thickness of 3 feet.
In this instance the term is used to describe a barrier that provides physical protection from the force of a blast. [ back to text ]
2Note that in our March 22, 1995, letter to Mr. Amsigner, we stated that use of a 3" warning tape mounted on a crane and posted around the swing radius perimeter qualified as an appropriate barricade and satisfied the requirements of §1926.550(a)(9). [ back to text ]
3Note that the General Industry standard for arc welders, in 29 CFR 1910.254(b)(5)(iv), states that "terminals for welding leads should be protected from accidental electrical contact . . . ," [emphasis added] but does not mandate such protection. [ back to text ]