At 3:40 a.m. on November 29, 1988, the Kansas City, MO Fire Department received an alarm indicating there was a fire at a highway construction project. The dispatcher directed Pumper 41 to respond to the truck fire. He added: “Pumper 41, use caution on your call. There’s information there may be explosives. It’s in a construction area…” Pumper 41 arrived at 0346 and found two separate fires, one involving a pickup truck and the other involving a trailer. There was another trailer parked less than 100 feet away.  Pumper 41 requested another pumper. The second pumper arrived at 0352 and began to fight the fire involving the trailer. The first company extinguished the fire in the pickup truck and proceeded to the other fire to assist the second company. At 4:08 a.m. a catastrophic explosion occurred. All six firefighters assigned to both companies were killed.  Approximately 40 minutes later, a second explosion occurred, followed by several minor explosions.

The explosions broke windows far from the site and were heard through a wide area. There were two large craters found where the two trailers had been. The first trailer explosion created a swimming pool-like crater, with a “deep part” 80 feet in diameter and eight feet deep connected to a smaller crater 20 feet in diameter and six feet deep. The second trailer explosion created a crater approximately 100 feet in diameter and eight feet deep.

The trailers contained over 20,000 pounds of ammonium nitrate/fuel oil (ANFO) mixture. There were no DOT placards visible nor were there any other markings on the trailers. In 1994 OSHA issued a regulation requiring employers who receive a shipment of hazardous materials that is required to be placarded to retain all required DOT markings including placards.

On November 17, 1990, as a direct result of this accident, Congress enacted the Hazardous Materials Transportation Uniform Safety Act of 1990 (HMTUSA), Public Law 101-615. HMTUSA mandated that the Secretaries of Labor, Transportation and the Treasury cooperate with each other to ensure that placards and labels required on hazardous materials and explosives, both in transportation and at stationary facilities, be retained until such materials have been removed to the extent that they no longer pose a safety risk. In response to the congressional mandate, OSHA issued a proposed rule to address HMTUSA requirements on September 10, 1993.

OSHA issued the final rule that requires employers who receive a package, transport vehicle, freight container, motor vehicle or rail freight car which contains a hazardous material and which is required to be marked, placarded, or labeled in accordance with the U.S. Department of Transportation's (DOT) Hazardous Materials Regulations, to retain the markings, placards, and labels on the package, transport vehicle, freight container, motor vehicle or rail freight car. Such markings, placards and labels generally must be retained on packages until the packaging is sufficiently cleaned of residue and purged of vapors to remove any potential hazards and retained on transport vehicles, freight containers, motor vehicles or rail freight cars until hazardous material which requires the marking or placarding is removed therefrom.

The rule was issued pursuant to section 6(b) of the Occupational Safety and Health Act of 1970 (the Act) and in accordance with section 29 of Public Law 101-615, the Hazardous Materials Transportation Uniform Safety Act of 1990 (HMTUSA).

Effective Date: This final rule took effect on October 17, 1994.


SUPPLEMENTARY INFORMATION: Public Law 101-615, the Hazardous Materials Transportation Uniform Safety Act of 1990 (HMTUSA), 104 Stat. 3244, was enacted by Congress on November 17, 1990. Section 29 of HMTUSA reads as follows:

Not later than 18 months after the date of enactment of this Act, the Secretary of Labor, in consultation with the Secretary of Transportation and the Secretary of the Treasury, shall issue under section 6(b) of the Occupational Safety and Health Act of 1970 (29 U.S.C. 655(b)) standards requiring any employer who receives a package, container, motor vehicle, rail freight car, aircraft, or vessel which contains a hazardous material and which is required to be marked, placarded, or labeled in accordance with regulations issued under the Hazardous Materials Transportation Act to retain the markings, placards, and labels, and any other information as may be required by such regulations on the package, container, motor vehicle, rail freight car, aircraft, or vessel, until the hazardous materials have been removed therefrom.

The Congressional rationale for this requirement was provided in Senate Report No. 101-449, (p. 16), as follows:

In November 1988, six Kansas City firemen were killed when the arson-caused fire they were fighting caused the violent explosion of an unmarked truck-trailer parked at a highway construction site. Because the trailer's hazardous materials placards had been removed, the firemen were unaware of the danger it posed. The Secretaries of Labor, Transportation and the Treasury should cooperate in order to ensure that placards and labels required on hazardous materials and explosives, both in transportation and at stationary facilities, be retained until such materials have been removed to the extent that they no longer pose a safety risk.

In response to the Congressional mandate, OSHA issued a proposed rule on September 10, 1993 to address the requirements of HMTUSA (58 FR 47690). A 30-day period was provided during which interested parties were invited to submit comments and information relative to the proposed rule. All comments submitted were collected in Docket No. H-022I, Exhibit No. 5, and prefixed with "Ex. 5" or "Ex. L5" (the latter denotes comments received after the close of the comment period). All comments received were reviewed and considered in developing this final rule. Most commenters supported OSHA's proposal; however, certain issues were raised that persuaded OSHA to modify the final standard in some respects or otherwise provide further clarification.

As with the proposed rule, OSHA believes that this final rule will impose no significant compliance burdens on industry. This was also substantiated in comments to the record.

Congress was specific in its mandate to OSHA for this rule, and the rule itself is limited to implementing the Congressional mandate. In this final rule, OSHA has slightly elaborated on the statutory language to the extent necessary to ensure that its requirements are clear and do not impose undue burdens on affected employers vis-a-vis other federal regulations. This regulation is essentially a continuation of the DOT's Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Employers may wish to consult those regulations in regard to complying with this section.


Discussion of Comments to NPRM and Summary and Explanation of the Final Rule

OSHA received 45 comments in response to its Notice of Proposed Rulemaking on the Retention of Markings and Placards. The NPRM requested specific information on costs, current practices with respect to the retention of DOT markings, placards and labels and any foreseeable problems in achieving the requirements of the proposed rule.

Most commenters supported the Agency's approach in responding to the congressional mandate for this action. However, some commenters pointed out potential sources of confusion for affected employers if appropriate modifications were not made to the final rule. Other commenters expressed a need for clarification of certain aspects of the proposal, particularly those relating to the scope of the standard and the relationship between DOT-required labeling and that required by OSHA's Hazard Communication Standard (HCS) at 29 CFR 1910.1200.

Only minimal information was submitted regarding costs. However, of those commenters who responded to this question, the majority agreed with OSHA's assessment that the rule would have only minimal economic impact. The commenters who stated that the costs would not be insignificant appeared to base their findings on what OSHA believes was a misunderstanding of the intent of the proposed rule.

Major Issues Raised

A. Scope

The NPRM did not make a distinction as to the size of packagings of hazardous materials for which employers would be required to retain the necessary DOT marking, label or placard. A significant number of commenters, however, pointed out that without restricting the regulation to bulk packaging, employers would be faced with confusing, redundant, and sometimes, inconsistent labeling requirements between DOT and OSHA's HCS. (There was no criticism about the retention provisions for transport vehicles, freight containers, motor vehicles or rail freight cars.) The HCS requires, in 29 CFR 1910.1200 (f), that manufacturers, importers, and distributors label, tag, or mark any containers of hazardous materials leaving the workplace with the identity of the hazardous material, appropriate hazard warnings and the name and address of the chemical manufacturer, importer or other responsible party. The HCS further requires that such labels, tags and markings be affixed in a manner that does not conflict with the HMR. Consequently, the HCS warning labels, tags or markings do not appear on the outer packagings of combination packagings (e.g., bottles in a box). The inner packagings are required to be labeled in accordance with the HCS, while the outside packaging is marked or labeled in accordance with the HMR. However, in some cases the DOT label and marking may appear on the same non-bulk packages as those required to be labeled under the HCS. This situation caused concern among commenters who questioned the need to retain DOT labels and marking where labeling was already required under HCS.

OSHA has crafted language which it concludes fulfills the intent of the statute, is protective of employees and meets the concerns of the commenters. All bulk packages must at all times retain their DOT marking until they are cleaned or purged. Such packages are often reshipped and the large size of the DOT marking is a safety advantage. DOT markings must be retained on non-bulk packages which will be reshipped. Clearly, the DOT marking is needed for reshipment.

However, OSHA concludes that the OSHA HCS label is fully protective for all employees and emergency responders for non-bulk packages which will not be reshipped. That label was designed to protect against all types of hazards. OSHA concludes therefore that it will be sufficient if an HCS label is on a non-bulk package when it is out of transportation, will not be reshipped and is at its final location at a factory or other worksite. This should respond to the commenters who feared that retaining both HCS and DOT labels at that stage might confuse their employees.

Additional concerns were expressed regarding the labeling of inner packagings of combination packagings.

It was not OSHA's intention to require labeling of containers that were not originally required to be labeled in accordance with the DOT's HMR. As previously stated, this final rule requires employers to retain labels on packages, this rulemaking does not require employers to label the packages. Inner packagings removed from an outer packaging that is required to be marked or labeled under DOT's HMR are not required to have the DOT marking or label affixed. However, those inner packages are required to have the OSHA HCS label. If the inner packages are to be reshipped, they would, of course, need the appropriate DOT label. In addition, packages which are excepted from the DOT's marking, labeling or placarding requirements, are not required under the DOT's HMR to be marked, labeled or placarded when stored at the workplace, but they would be required to be labeled under the OSHA HCS.

One commenter pointed out that sometimes employers receive hazardous materials which have the DOT-required labels affixed and subsequently store them at remote sites in trailers that are not intended for transportation and therefore are not required to be placarded (Ex. 5-2). The situation that the commenter raises is a small part of a much broader problem. OSHA believes that the communication of hazards at all storage locations (e.g. trailers, warehouses and storage tanks) is an important area for consideration. However, this issue is not within the scope of the statute directing this rulemaking.

In another matter related to the scope of this rule, the American Trucking Association requested a clarification as to whether the rule placed an obligation on operators of transport vehicles (5-22). Similarly, the Agricultural Retailers Association (Ex. L5-37) wanted assurance that the responsibility for retaining DOT placards, markings and labels transfers to the receiving employer. In response to both concerns, the final rule applies to the employer who receives the containers of hazardous materials and not the person responsible for transporting such material unless the material is still under the control of the transporter at its final destination when it is out of transportation.


B. Discrepancy Between DOT and OSHA Definitions of Flammable and Combustible

A number of commenters raised the issue of the discrepancy between DOT and OSHA with respect to the definitions of flammable and combustible liquids. Commenters correctly stated that OSHA defines a flammable liquid as one with a flashpoint less than 100 deg. F. and a combustible liquid as one with a flashpoint between 100 deg. F and 200 deg. F. Commenters stated that DOT defines a flammable liquid as a material with a flashpoint of below 141 deg. F. and a combustible liquid as a material with a flash point greater than 141 deg. F but below 200 deg. F. OSHA has conferred with the DOT on this issue and was informed that while these statements are correct, DOT does allow in 49 CFR 173.150 (f), for domestic transportation, flammable liquids with a flash point greater than 100 deg. F to be reclassed as a combustible liquid. A combustible liquid is not required to be labeled under DOT's HMR and, therefore, the provisions of this rule regarding the retention of required DOT labels would not apply. OSHA believes that this clarification should satisfy the concerns of commenters who raised the issue of combustible and flammable liquids being defined differently by OSHA and DOT. However, the broader issue of different definitions presents other technical, policy and legal issues and involves many institutions nationally and internationally. These issues cannot be properly addressed nor be solved in this rulemaking.


C. Duration Required for Retention of Hazard Warnings

Paragraph (a)(1) of the proposed standard required that markings, placards and labels remain on the package, freight container, etc. of hazardous material until the hazardous materials are removed therefrom so that they no longer pose a health or safety risk. A number of comments suggested that the language in this provision was ambiguous and employers would be uncertain as to when DOT labels, placards and markings could be removed without being in violation of the rule. Various suggestions were offered regarding how to clarify this issue, ranging from deleting paragraph (a)(1) to allowing removal of the markings and placards as long as no more than a de minimis amount of the hazardous material remains in a container (Ex 5-10).

In the final standard OSHA has amended the language in paragraphs (a) and (b) so that it is now clear. Employers need only retain the DOT label, marking or placard until such time as the packaging which contained the hazardous material is sufficiently cleaned of residue and purged of vapor to remove any potential hazard. Paragraph (b), which requires the retention of markings and placards on transport vehicles, etc., states that markings and placards may be removed from transport vehicles if the transport vehicle no longer contains hazardous material subject to the marking or placarding requirements of the DOT's HMR. In the alternative, employers will be in compliance if they choose to retain the appropriate DOT hazard warning on packaging containing only the residue of the hazardous chemical in the same manner as when it contained a greater quantity of the hazardous material.

In the case where an outside package, (including transport vehicles), contains smaller packages of hazardous materials, DOT hazard warnings need be retained on the outside packaging only until the inner packages are removed. However, if a contained package leaks into the outer packaging, the cleaning and purging requirement applies.


D. Other Issues

The Edison Electric Institute (Ex 5-26) requested an exemption from this standard for Nuclear Regulatory Commission licensees whose radioactive material handling practices are already regulated by the NRC. This request was made on the basis of a Memorandum of Understanding (MOU) between the NRC and OSHA which gives the NRC jurisdiction in regulating most situations involving hazards that may be associated with NRC-licensed nuclear facilities, including worksite conditions which affect the safety of radioactive materials and thus the health and safety of workers.

The MOU, however, is not relevant in this case since OSHA is not regulating radioactive materials themselves but is only requiring an extension of DOT requirements. Since the DOT requirements already apply to employers handling radioactive materials, this standard does not represent any change. Therefore, including an exemption in the standard is not appropriate.

There was some confusion regarding paragraph (a)(2) of the proposed rule which required that markings, placards and labels be maintained in a manner that ensures the legend is visible. In effect, all that was intended by this provision was to assure that the label, placard, or marking be kept sufficiently clean (unobscured by dust, dirt, mud, etc.) that it would be easily seen in the event of an emergency or as necessary to prevent a hazardous situation. The provision was never intended to place restrictions on how or where DOT-labeled materials should be stored. However, since one commenter objected to the use of the term "legend," the provision has been revised as paragraph (c) in the final rule to read: "Such markings, placards and labels shall be maintained in a manner that assures they are readily visible." This does not mean that non-bulk packages with DOT labels that are stored in a warehouse (e.g. cartons containing 4-gallon cans of a hazardous material) have to be arranged in a manner which allows every label to be in view at all times. Rather it requires that where DOT hazard warnings are required to be retained, that such warnings are maintained in a manner that ensures that the message which the hazard warning is intended to convey is not compromised. In other words, at least some labeling should be visible for each type of hazardous material.

Additional minor changes were also suggested that OSHA agrees are appropriate for completeness and has incorporated in the final rule. Specifically, the title of the final rule has been amended to include the term "label." The terms "aircraft" and "vessel" have been deleted from the regulatory text as there are no specific DOT requirements to affix warning labels to an aircraft or vessel. The term "container" was also changed to "freight container" as Ex. 5-33 suggested. The section has been editorially revised in order to be more consistent with the DOT's HMR and in order that the section is more readily understandable. For example, the requirements for packages versus transport vehicles have been separated into two separate paragraphs.

In a similar matter concerning the authority granted the Agency by the HMTUSA legislation, at least one commenter (Ex. 5-4) suggested that since the real issue addressed in the legislation was hazard communication, the requirement to retain DOT hazard warnings should have been integrated in the Hazard Communication Standard in lieu of issuing a separate regulation. OSHA, however, believes that Congress was quite specific in its instructions to the Secretary of Labor that this requirement apply to DOT regulations and that it be addressed as a separate rule. Paragraph (d) does, however, make this final rule better integrated with the Hazard Communication Standard.

Finally, Amoco (Ex. 5-21) raised the issue of whether the rule would apply to an employer's current inventory of DOT-labeled materials and whether changes to the existing markings and labels would be required. In response to this comment, the Agency is allowing 90 days following publication of the final rule in the Federal Register for employers to come into compliance. The rule requires no changes in the content of the label. However, OSHA is providing what it believes is sufficient time for employers to replace labels, markings or placards that may have been removed, or to empty containers of hazardous materials. Once the effective date of the rule has passed, employers will be subject to OSHA citations if packages, transport vehicles, freight containers, etc. of hazardous materials covered by DOT's HMR are present in the workplace, do not have the appropriate DOT hazard warning and violate the standard. It is not possible for OSHA compliance officers to readily know the date transport vehicles or packages were received and DOT warnings were removed. The 90-day period is a realistic time in which to replace removed placards, markings or labels or to empty containers.

Because Congress has directed that OSHA issue this regulation for all employers covered by the OSH Act, this notice includes separate but identical standards for general industry (1910.1201), construction (1926.60), shipyards (1915.100), marine terminals (1917.29) and longshoring (1918.100). The general industry standard will also be added to the list of Part 1910 standards which apply to agricultural operations, as a new paragraph (a)(7) of 1928.21.

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