• Record Type:
    OSHA Instruction
  • Current Directive Number:
    PUB 8-1.9
  • Old Directive Number:
    PUB 8-1.9
  • Title:
    Nationally Recognized Testing Laboratory (NRTL) Accreditation Program (29 CFR 1910)
  • Information Date:
Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

OSHA Instruction PUB 8-1.9 Sept 10, 1991 Directorate of Technical Support

Subject: Nationally Recognized Testing Laboratory (NRTL) Accreditation Program (29 CFR 1910.7)

A. Purpose. This instruction provides information on the NRTL accreditation program which is administered by the Directorate of Technical Support and implemented by the Office of Variance Determination. As a result of the new program, additional laboratory organizations are now authorized to certify products.

B. Scope. This instruction applies OSHA-wide.

C. Background. The Occupational Safety and Health Administration (OSHA) published a final rule, "Safety Testing or Certification of Certain Workplace Equipment and Materials; 29 CFR 1907 and 1910", in the Federal Register of April 12, 1988. This document included two important facets: the modification of the language of those provisions in 29 CFR 1910 that require product "certification" (by whatever term used) by organizations such as Underwriters Laboratories Inc. and Factory Mutual Engineering Corporation, to specify that these certifications be accomplished by a nationally recognized testing laboratory (NRTL), and; the establishment of criteria by which a testing organization could apply for and be accredited as an NRTL to test and certify these products.

While our program refers to the "recognition" of applicants, the term is used in the sense that most within the testing and certification community use "accreditation." For consistency and accuracy, we will also refer to "accrediting" rather than "recognizing" an applicant. We refer to the program, as the "NRTL accreditation program" and the laboratories that are accredited under this program are "nationally recognized testing laboratories" or "NRTLs."
Prior to June 13, 1988, Section 1910 referenced Underwriters Laboratories, Inc. (UL) and Factory Mutual Research Corporation (FM) as the only two laboratory organizations authorized to certify products for use in the workplace. UL and FM were temporarily recognized (accredited) by OSHA at the outset of the program to insure a smooth transition.
Prior to the end of this period, July 13, 1993, both must apply for and receive formal accreditation to enable them to continue to certify products under OSHA's requirements. The accreditation procedure necessitates, among other requirements, on-site investigations of the applicants' facilities. The worldwide locations and numbers of testing facilities of the Underwriters Laboratories (UL) alone, as well as the estimated number of test standards to be requested, will necessitate extensive manpower needs.
OSHA's obligations under the specific rule, 29 CFR 1910.7 -
"Definition and requirements for a nationally recognized testing laboratory," and Appendix A to 29 CFR 1910.7 - "OSHA Recognition Process for Nationally Recognized Testing Laboratories," include allowing all applicants an equal opportunity to become accredited to test and certify products requiring certification under OSHA's regulations, and to assure that each applicant satisfies the requirements for NRTL accreditation.
This instruction will provide background on Section 1910.7 and information concerning the laboratory organizations accredited to certify products. Compliance Safety and Health Officers (CSHOs) will begin to see labels other than those of UL and FM on products requiring certification since, to date, five additional organizations have been accredited.

D. Requirements for NRTL Accreditation. OSHA requires that an applicant for NRTL recognition be a combination of testing laboratory and certifying body. OSHA's recognition is based upon the applicant's ability to adequately perform both functions. The applicant's identification procedure must include testing and evaluation, quality control, follow-up procedures and control of its certification mark.

In general, most of the equipment or materials (products) which the OSHA standards require to be certified are of an electrical nature. The standards also require certification of products which are: LPG appliances; fire detection or extinguishment systems; or acetylene apparatus. Other miscellaneous products or categories of products may also require certification. A nationally recognized testing laboratory, within the context of the OSHA regulation, is an organization which can test and certify products for safety.

E. Specific Requirements for Accreditation. To be accredited as a NRTL, the applicant must meet specific requirements, including the following:

1. For each product to be certified, the NRTL must demonstrate the capability to determine its conformance with appropriate test standards. This would be determined, in part, by the adequacy of the NRTL's testing equipment and facilities, written testing procedures, calibration and quality control programs, as well as by the capability of the professional staff.
2. The NRTL must provide control procedures for identifying the certified products, provide product evaluation services to assure conformance with the test standards during the production run at the manufacturing site, and assure proper use of its identifying mark or label on the product in the field.
3. The NRTL must maintain effective procedures for producing creditable findings or reports that are objective and without bias, and for handling complaints and disputes under a fair and reasonable system.
4. Finally, any testing organization desiring NRTL status shall request that OSHA evaluate its testing and control programs against the requirements described above for any of the equipment or material test standards it may specify. The recognition procedure is detailed in Appendix A of 29 CFR 1910.7. OSHA invites and encourages public participation in the recognition procedure.
5. Recognitions are for a period of five years and OSHA maintains continuing surveillance over its NRTLs to assure conformance with the requirements of the rule as well as the terms of the recognition.

F. Review of Applicant's Request for Accreditation.

1. The review of an applicant's request for accreditation as an NRTL is as follows:
          a.   Determination of the procedural and technical
                adequacy;
b. Resolution of any legal issues with the Office the Solicitor;
c. Prompt determination of preliminary decision to grant or deny application after any requested additional information has been received and the on-site inspection report has been reviewed;
d. Assembling of the necessary technical data for preparation of a notice of the preliminary decision for publication in the Federal Register. This notice shall include mention of the supporting evidence presented by the applicant for each element of the criteria and provision for a 60 day public comment period;
e. Evaluation of technical data in conjunction with any public comments received. Determination of necessity of on-site inspection based upon any of the facts;
f. Preparation and forwarding to the applicant of a letter of recognition delineating the product(s) authorized to be listed, labeled, or accepted;
g. Assembling of the necessary technical data and preparation of the Federal Register document to include the supporting evidence assuring that the applicant has met the criteria for approval as a nationally recognized testing laboratory; and
h. Forwarding of the document recognizing the applicant as an NRTL to the Assistant Secretary for approval and publication in the Federal Register.
2. After receipt of the necessary administrative and technical data from the applicants, it generally requires an average of six months, including the 60 day Federal Register comment period and the on-site laboratory(s) evaluation, to become an NRTL.
3. As we continue to develop and refine our operating procedures to assure timely decisions for a laboratory organization seeking recognition as an NRTL, we believe that the laboratory accreditation/recognition program is a significant activity and could become a critical area. The program has the potential to expand into other safety and health areas such as: personal protective equipment, crane operations, mechanical power press operations, and the like.

G. NRTL Staff Responsibility. As mandated by the NRTL rule, the NRTL office staff will perform the following administrative and technical functions during the laboratory accreditation process:

1. Maintain case files of all NRTL applicants.
2. Maintain the list of NRTLs and the test standards for which each is accredited on the OSHA Computerized Information System (OCIS).
3. Prepare the "paper work" necessary for the administration of the program, including memoranda, letters of recognition, documents requiring publication in the Federal Register, and all of the documents for the Docket Office of the Technical Data Center.
4. Inspect the physical facilities.
5. Ascertain the availability and proper use of test equipment and materials.
6. Examine calibration/repair methods of test equipment.
7. Assure that test reports contain sufficient information to determine compliance with standards.
8. Confirm that test reports contain sufficient information to determine compliance with standards.
9. Determine that records are adequately maintained and secured.
10. Examine the quality assurance program.

H. Foreign Laboratory Organizations. This NRTL rule provides authority for foreign laboratory organizations to seek accreditation as NRTLs under the OSHA program. As a result, OSHA is required to seek counsel with the Office of the U.S. Trade Representative to determine the testing/certification accreditation practices of the foreign government. The European Communities' Free Trade Agreement becomes effective on January 1, 1993, by which time the European Organization for Testing and Certification (EOTC) is to have selected accrediting organizations ("Certified Bodies") to represent many of the nations of the world. If the Occupational Safety and Health Administration, through the Nationally Recognized Testing Laboratory program, is selected as one of the accrediting organizations representing the United States, we can anticipate a considerable increase in applications for NRTL recognition from domestic and foreign laboratory organizations. We are presently engaged in discussions with members of the Office of the Trade Representative to seek guidance on issues dealing with foreign laboratory organizations seeking accreditation from OSHA. Two Canadian organizations have submitted applications for recognition as NRTLs.

I. Certification Labels. As stated, CSHOs will begin to find labels of firms other than UL and FM on products. When this occurs, OCIS may be queried to determine whether the laboratory has been accredited. For additional information, the OSHA National Office of Variance Determination may be contacted at (FTS) 523-7193 or (202) 523-7193.

J. State Plan States. When the Federal nationally recognized testing laboratory accreditation standard was adopted, the State plan States were given the choice of accepting only Federal OSHA accreditation of testing laboratories as NRTLs, or establishing their own laboratory accreditation program. However, any State establishing its own program still had to accept accreditation by NRTLs for testing of equipment and materials where State safety requirements were the same as the Federal. Any independent State program is only for different State equipment and material requirements and is limited to in-State applicability and enforcement. The State program must also be at least as effective as the Federal program. (See OSHA Instruction STP 2-1.147A). Almost all the States have chosen to accept only the Federal laboratory accreditation program.

K. Accredited Laboratories. To date, the following six laboratory organizations have been accredited by OSHA to certify certain specified products or categories of products for use in the workplace.

Underwriters Laboratories Inc. (UL) 333 Pfingsten Road Northbrook, Illinois 60062 (708)272-8800
Factory Mutual Research Corporation (FMRC) 1151 Boston-Providence Turnpike P.O. Box 9102 Norwood, Massachusetts 02062 (617)762-4300
MET Electrical Testing Company, Inc. (MET) Laboratory Division 916 West Patapsco Avenue Baltimore, Maryland 21230 1-800-638-6057 (301)354-2200
Dash, Straus and Goodhue, Inc. (DSG) 593 Massachusetts Avenue Boxborough, Massachusetts 01719 (508)263-2662
ETL Testing Laboratories, Inc. (ETL) Cortland Safety Division Industrial Park Cortland, New York 13045 1-800-345-3851 (607)753-6711
American Gas Association Laboratories (AGA) 8501 East Pleasant Valley Road Cleveland, Ohio 44131 (216)524-4990
Communication Certification Laboratory (CCL) 1940 West Alexander Street Salt Lake City, Utah 84119 (801)972-6146

L. Certification References The attached document references citations in the General Industry Standards (29 CFR 1910) which require product (equipment, material) certification (listing and labeling) by an NRTL.

Gerard F. Scannell Assistant Secretary
Distribution: National, Regional, and Area Offices, All COSHO, State Designees, 7(c)(1) Consultation Project Managers, OSHA Training Institute, NIOSH Regional Program Directors

APPENDIX A

Specific References to Certification

(other than Subpart S)

NOTE: Where feasible, only one reference will be cited for each type of approved (certified) product.

1910.28 - Safety Requirements for Scaffolding

     28(f)(2) - The (masons' adjustable multiple-point suspension) scaffold
                shall be provided with hoisting machines that meet the
                requirements of a nationally recognized testing laboratory.
     28(g)(3) - When hoisting machines are used on two-point suspension
                scaffolds, such machines shall be of a design tested and
                approved by a nationally recognized testing
     28(h)(2) - The hoisting machine and its supports (of a stone setters'
                adjustable multiple-point suspension scaffold) shall be of a
                type tested and listed by a nationally recognized testing
                laboratory.
     28(i)(1) - The scaffolding, including power units or manually operated
                units (of a single-point adjustable suspension scaffold),
                shall be of a type tested and listed by a nationally
                recognized testing laboratory.

1910.37 - Means of Egress - General

        37(a) - Exits to consist only of approved (exit) components, either an
                integral part of or permanently affixed to the building.

1910.38 - Employee Emergency Plans and Fire Prevention Plans

38(a)(3)(i) - An approved employee alarm system to be established.

1910.66 - Powered Platforms for Building Maintenance

     66(f)(8)(i) - Electrical wiring and equipment shall comply with
                   Subpart S of this Part, except as otherwise required by
                   this section.

1910.94 - Ventilation

94(c)(3)(iii)(a) - Overspray filters in (spray booths) shall be non-
combustible or, if combustible, not in excess of class 2 filters as listed by UL.

1910.106 - Flammable and Combustible Liquids

     106(b)(2)(iv)(f) - Tanks and pressure vessels storing class IB and IC
                        liquids shall have venting device or approved
                        flame arresters.
     106(b)(4)(iv)(d) - Each opening for manual gaging in a tank installed
                        inside a building shall have a check valve or
                        other approved device.
     106(d)(4)(i) - Openings to inside storage rooms (for containers and
                    portable storage) shall have approved self-closing
                    fire doors.
106(d)(7)(ii) - When provided, sprinklers shall be approved.
     106(f)(8) - The design of fire-control devices (small hose,
                 portable fire extinguishers) to be in accordance with
                 approved engineering standards.
     106(g)(3)(ii) - Approved dispensing units at automotive service stations
                     may be located inside of buildings.
                     The dispensing area to be provided with approved
                     mechanical or gravity ventilation system. When
                     dispensing units are below grade, approved mechanical
                     ventilation to be used, and dispensing area protected
                     by approved automatic sprinkler system.
     106(g)(3)(iv)(c) - Class I liquids to be dispensed by approved pumps
                        taking suction through top of container or approved
                        self-closing faucets.
     106(g)(3)(vi)(a) - Dispensers for Class I liquids to have listed manual
                        or automatic-closing type hose nozzle valves.
106(g)(3)(vi)(b) - Automatic-closing type valves may use approved latch-

open device.
     106(g)(4)(i)(b) - Dispensing at marine service stations to be by
                       approved dispensing units w/wo integral pumps.
     106(g)(9) - Each service station to have fire extinguisher with approved
                 classification of 6 B, C.
     106(h)(4)(ii)(b) - Approved flexible connectors (piping, valves, and
                        fittings) may be used (in processing plants).
                        Approved hose may be used at transfer stations.
     106(h)(6)(i) -  Approved portable fire extinguishers of appropriate
                     size, type, and number to be provided.
     106(h)(6)(ii)(d) - Approved automatic sprinkler system or equivalent
                        extinguishing system may be used.  If special
                        extinguishing system (e.g., foam, CO2, dry chemical)
                        is provided, approved equipment shall be used. . .

1910.107 - Spray Finishing Using Flammable and Combustible Materials

     107(b)(5)(vi) - Clean filters or filter to have combustibility not in
                     excess of class 2 filters as listed by UL.
     107(e)(3) - Approved portable tanks or approved safety cans to be used
                 for handling flammable or combustible liquids.
     107(h)(2) - Fixed electrostatic apparatus and devices used with
                 coating operations to be approved types.
     107(h)(12) - All spraying areas to have automatic sprinklers or other
                  approved automatic extinguishing equipment (fixed CO2 or
                  dry chemical system).
     107(i)(3) - Electrostatic hand spray apparatus and devices to be
                 approved.
     107(l)(7)(i) - Electrostatic fluidized beds and associated equipment
                    to be approved.

1910.108 - Dip Tanks Containing Flammable or Combustible Liquids

     108(g) - Areas in vicinity of dip tanks to have approved manual fire
              extinguishers suitable for flammable and combustible liquid
              fires.
     108(h)(1)(vii) - The drain valve of the dip tank to be operated
                      automatically with approved heat actuated devices.

1910.109 - Explosives and Blasting Agents

     109(d)(2)(iii)(a) - Each motor vehicle for transporting explosives to
                         have. . .(approved) extinguishers having a rating of
                         at least 10 B C.

1910.110 - Storage and Handling of Liquefied Petroleum Gases

     110(b)(2)(i) - Each system using DOT containers to have approved
                    container valves, connectors, manifold valve assemblies,
                    and regulators.
     110(b)(2)(ii) - Each system. . .using containers of 2000 gals. or less
                     water capacity. . .shall consist of a container assembly
                     and one or more regulators, and may include other parts.
                     The system as a unit or the container assembly as a
                     unit, and the regulator or regulators, to be
                     individually listed.
     110(b)(2)(iii) - In systems using containers of over 2000 gals. water
                      capacity, each regulator, container valve, excess flow
                      valve, gaging device, and relief valve on or at the
                      container to be listed.
     110(b)(20)(i) - . . .new commercial and industrial gas consuming
                          appliances shall be approved.
     110(b)(20)(iii) - Unattended heaters used inside buildings for the
                       purpose of animal or poultry production to be equipped
                       with an approved device designed to shut off the flow
                       of gas to the main burners, and pilot if used, in the
                       of flame extinguishment.
     110(c)(5)(i)(g)(1) - (With cylinder systems used inside of buildings)
                          hose and hose connections to be listed.
     110(c)(5)(i)(h) - Portable heaters, including salamanders, to be
                       equipped with an approved automatic device to shut off
                       the flow of gas to the main burner, and pilot if used,
                       in the event of flame extinguishment.
     110(d)(3)(iii) - (With systems using non-DOT containers) all openings in
                      a container to be equipped with automatic excess flow
                      valves, with some exceptions.:
     110(d)(3)(iv) - An excess flow valve is not required in the withdrawal
                     service line providing the following are complied with,
                     among which is:
     110(d)(3)(iv)(e) - An approved pressure-reducing regulator is directly
                        attached to the outlet of the shutoff valve . . .
     110(d)(3)(viii) - Containers of 125 gals. water capacity. . . to be
                       provided with an approved device for liquid
                       evacuation. . .
     110(d)(7)(x) - (With permanently installed, interconnected containers)
                    flexible connections. . . shall be approved.
     110(d)(7)(xi) - Container assemblies listed for interchangeable
                     installation above or under ground. . .
     110(e)(5)(ii) - (With LPG as a motor fuel) the filling connection shall
                     be fitted with an approved double back-pressure check
                     valve. . .
     110(e)(5)(iii) - . . .filling connections equipped with approved
                      automatic back-pressure check valves, and safety relief
                      valves, all connections to containers. . . shall be
                      equipped with approved automatic excess flow valves. .
     110(e)(5)(iv)(e)(1) - (With removable fuel containers) . . . an approved
                           automatic quick-closing coupling. . .
     110(e)(9)(i) - Approved automatic pressure reducing equipment shall be
                    installed. . .
110(e)(9)(ii) - An approved automatic shutoff valve shall be provided. .
     110(f)(5)(iv) - Each opening from (special) storage rooms to other parts
                     of the building shall be protected by a (listed) 1 1/2
                     hour (B) fire door. . .
1910.111 - Storage and Handling of Anhydrous Ammonia
111(b)(1) - Each appurtenance to be approved. . .
     [111(a)(2)(i) - "Appurtenances"--All devices such as pumps, compressors,
                     safety relief devices, liquid-level gaging devices,
                     valves and pressure gages.]

1910.157 - Portable Fire Extinguishers

     157(c)(2) - Only approved portable fire extinguishers shall be used to
                 meet the requirements of this section.

1910.159 - Automatic Sprinkler Systems

     159(c)(1)(ii) - Only approved equipment and devices to be used in the
                     design and installation of automatic sprinkler systems
                     used to comply with this standard.
159(c)(8)(i) - Only approved sprinklers are used on systems.

1910.160 - Fixed Extinguishing Systems, General

     160(a)(1) - This section applies to all fixed extinguishing systems. . .
                 except automatic sprinkler systems.
     160(b)(1) - Fixed extinguishing system components and agents to be
                 designed and approved for use on the specific fire hazards
                 they are expected to control or extinguish.
     160(b)(13) - Automatic detection equipment to be approved. . . in
                  accordance with 1910.164 - Fire Detection Systems.

1910.161 - Fixed Extinguishing Systems, Dry Chemical

     161(a) - This section applies to all fixed extinguishing systems using
              dry chemical as the extinguishing agent, installed to meet a
              particular OSHA standard.  These systems to also comply with
              1910.160 - Fixed Extinguishing Systems, General.

1910.162 - Fixed Extinguishing Systems, Gaseous Agent

     162(a)(1) - This section applies to all fixed extinguishing systems
                 using a gas as an extinguishing agent, installed to meet a
                 particular OSHA standard.  These systems to also comply with
                 1910.160.
     162(b)(1) - (All gaseous extinguishing) agents used for initial supply
                 and replenishment to be of the type approved for the
                 system's application.

1910.163 - Fixed Extinguishing Systems, Water Spray and Foam

     163(a) - This section applies to all fixed extinguishing systems using
              water or foam solution, installed to meet a particular OSHA
              standard.  These systems to also comply with 1910.60.

1910.164 - Fire Detection Systems

     164(a) - Section applies to all automatic fire detection systems
              installed to meet the requirements of a particular OSHA
              standard.
     164(b) - All (fire detection) devices and equipment to be approved for
              the purpose for which they are intended.

1910.165 - Employee Alarm Systems

     165(c)(1) - All devices, components, combinations of devices or systems
                 constructed . . .to comply with this standard to be
                 approved.  Steam whistles, air horns, strobe lights or
                 similar lighting devices, or tactile devices meeting the
                 requirements of this section are considered to meet the
                 requirement for approval.

1910.178 - Powered Industrial Trucks

     178(a)(3) - Approved trucks shall bear a label or some other identifying
                 mark indicating approval by the testing laboratory.
     178(a)(7) - . . ."approved truck" or "approved industrial truck" means a
                 truck that is listed or approved for fire safety
                 purposes for the intended use by an NRTL.
      178(d) - Power-operated industrial trucks originally approved for use
               of gasoline, when converted to LPG, may be used in those
               locations where certain type trucks have been previously
               specified.
     178(m)(11) - Only approved industrial trucks shall be used in hazardous
                  locations.
     178(q)(12) - Industrial trucks originally approved for gasoline fuel may
                  be converted to LPG fuel. . .Such conversion equipment
                  shall be approved.

1910.180 - Crawler Locomotive and Truck Cranes

     180(i)(4)(i) - Refueling with small portable containers to be done with
                    an approved safety type can equipped with an automatic
                    closing cap and flame arrester.

1910.181 - Derricks

     181(j)(4)(i) - Refueling. . .with approved safety type containers
                    equipped with automatic closing cap and flame arrester.

1910.253 - Oxygen-Fuel Gas Welding and Cutting

     253(a)(2) - Under no condition shall acetylene be. . .piped (except
                 in approved cylinder manifolds). . .
     253(a)(3) - Only approved apparatus such as torches, regulators or
                 pressure-reducing valves, acetylene generators and
                 manifolds shall be used.
     253(c)(1)(i) - Manifolds (fuel gas) shall be approved either
                    separately for each component part or as an assembled
                    unit.
     253(c)(1)(v) - High-pressure fuel gas manifolds to be provided with
                    approved pressure-regulating devices.
     253(c)(2)(i) - Manifolds (oxygen) shall be approved either
                    separately for each component part or as an assembled
                    unit.
     253(c)(2)(vi) - High-pressure oxygen manifolds to be provided with
                     approved pressure-regulating devices.
     253(c)(4)(v) - Portable outlet headers for fuel-gas service to be
                    provided with an approved hydraulic back-pressure
                    valve. . .unless an approved pressure-reducing
                    regulator, an approved back-flow check valve, or an
                    approved hydraulic back-pressure valve is installed
                    at each outlet.
     253(c)(5)(11) - All manifolds and parts used in methods of
                     manifolding to be used only for the gas or gases for
                     which they are approved.
     253(c)(5)(iii) - When acetylene cylinders are coupled, approved flash
                      arresters shall be installed between the cylinder and
                      the coupler block.
     253(e)(1) - Equipment shall be installed and used only in the service
                 for which it is approved. . .
253(e)(3)(ii) - Approved protective equipment. . .
     253(e)(3)(ii)(c)(2) - Backflow protection to be provided by an
                           approved device that will prevent O2 from
                           flowing into the fuel system or the reverse.
     253(e)(3)(ii)(c)(3) - Flash-back protection shall be provided by
                           an approved device that will prevent flame from
                           passing into the fuel-gas system.
     253(e)(3)(ii)(c)(4) - Back-pressure protection to be provided by an
                           approved pressure-relief device. . .
     253(f)(2)(i) - The total hourly output of a generator not to exceed
                    rate for which it is approved and marked.
     253(f)(4)(i)(e) - Unless otherwise specifically approved, generators
                       not to fitted with continuous drain connections
                       leading to sewers. . .
     253(f)(4)(iv)(a) - The compressor or booster system to be of an
                        approved type.
     253(f)(5)(i)(a) - All portable generators to be of a type approved
                       for portable use.
     253(f)(6)(i)(i) - Windows in partitions shall be wired glass and
                       approved metal frames with fixed sash.

1910.265 - Sawmills

     265(d)(2)(iv)(c) - Boat fuel to be transported and stored in approved
                        safety containers.
     265(i) - The requirements of Subpart L of this part to be complied with
              in providing the necessary fire protection for sawmills.

1910.266 - Pulpwood Logging

     266(c)(4)(iii) - An approved fire extinguisher to be provided
                      at locations where machines are operating and/or on
                      each vehicle.
     266(c)(4)(iv) - Fuel to be stored only in approved well-marked
                     containers. . .

APPENDIX B

General Reference to Certification

SUBPART S - ELECTRICAL

1910.303 - General Requirements
          303(a) Approval. The conductors or equipment required or permitted
                           by this subpart shall be acceptable only if
                           approved.