[Federal Register Volume 69, Number 88 (Thursday, May 6, 2004)]
[Proposed Rules]
[Pages 25470-25478]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-10277]



[[Page 25469]]

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Part II





Department of Transportation





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Research and Special Programs Administration



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49 CFR Parts 171, 172, 173, 175, and 178



Hazardous Materials Regulations: Transportation of Compressed Oxygen, 
Other Oxidizing Gases and Chemical Oxygen Generators on Aircraft; 
Proposed Rule

  Federal Register / Vol. 69, No. 88 / Thursday, May 6, 2004 / Proposed 
Rules  

[[Page 25470]]


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DEPARTMENT OF TRANSPORTATION

Research and Special Programs Administration

49 CFR Parts 171, 172, 173, 175, and 178

[Docket No. RSPA-04-17664 (HM-224B)]
RIN 2137-AD33


Hazardous Materials Regulations: Transportation of Compressed 
Oxygen, Other Oxidizing Gases and Chemical Oxygen Generators on 
Aircraft

AGENCY: Research and Special Programs Administration (RSPA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: RSPA proposes to amend the Hazardous Materials Regulations to 
require that cylinders of compressed oxygen and packages of chemical 
oxygen generators be placed in an outer packaging that meets certain 
flame penetration and thermal resistance requirements when transported 
aboard an aircraft. RSPA is also proposing to: (1) Revise the pressure 
relief device setting limit on cylinders of compressed oxygen 
transported aboard aircraft; (2) limit the types of cylinders 
authorized to transport compressed oxygen aboard aircraft; (3) prohibit 
the transportation of all oxidizing gases, other than compressed oxygen 
aboard cargo and passenger aircraft; and (4) convert most of the 
provisions of an oxygen generator approval into the HMR. This proposal 
would increase the level of safety associated with transportation of 
these materials aboard aircraft. This proposal was developed jointly 
with the Federal Aviation Administration (FAA).

DATES: Submit your comments on or before August 13, 2004.

ADDRESSES: You may submit comments by any of the following methods:
     Web site: http://dms.dot.gov. Follow the instructions for 
submitting comments on the DOT electronic docket site.
     Fax: 1-202-493-2251.
     Web site: http://regulations.gov. Follow instructions for 
submitting comments.
     Mail: Docket Management System; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-402, 
Washington, DC 20590-001.
     Hand Delivery: To the Docket Management System; Room PL-
401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., 
Washington, DC between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal Holidays.
    Instructions: You must include the agency name and docket number 
RSPA-04-17664 (HM-224B) or the Regulatory Identification Number (RIN) 
for this notice at the beginning of your comment. For detailed 
instructions on submitting comments and additional information on the 
rulemaking process, see the Public Participation section of this 
document. Note that all comments received will be posted without change 
to http://dms.dot.gov including any personal information provided. 
Please see the Privacy Act section of this document.

FOR FURTHER INFORMATION CONTACT: John A. Gale, Office of Hazardous 
Materials Standards, telephone (202) 366-8553, Research and Special 
Programs Administration, U.S. Department of Transportation, 400 Seventh 
Street, SW., Washington, DC 20590-0001 or David Catey, Office of Flight 
Standards, (202) 267-3732, Federal Aviation Administration, U.S. 
Department of Transportation, 800 Independence Avenue, SW., Washington 
DC 20591.

SUPPLEMENTARY INFORMATION:

I. Background

    The National Transportation Safety Board found that one of the 
probable causes of the May 11, 1996 crash of ValuJet Airlines flight 
No. 596 was a fire in the airplane's cargo compartment that was 
initiated and enhanced by the actuation of one or more chemical oxygen 
generators that were being improperly carried as cargo. Following that 
tragedy, in which 110 lives were lost, the Department of Transportation 
has:

--Prohibited the transportation of chemical oxygen generators 
(including personal-use chemical oxygen generators) on board passenger-
carrying aircraft and the transportation of spent chemical oxygen 
generators on both passenger-carrying and cargo-only aircraft, 61 FR 
26418 (May 24, 1996), 61 FR 68952 (Dec. 30, 1996), 64 FR 45388 (Aug. 
19, 1999);
--Issued standards governing the transportation of chemical oxygen 
generators on cargo-only aircraft (and by motor vehicle, rail car and 
vessel), including the requirement for an approval issued by RSPA, 62 
FR 30767 (June 5, 1997), 62 FR 34667 (June 27, 1997);
--Upgraded fire safety standards for Class D cargo compartments on 
aircraft to require a smoke or fire detection system and a means of 
suppressing a fire or minimizing the available oxygen, on certain 
transport-category aircraft, 63 FR 8033 (Feb. 17, 1998); and
--Imposed additional requirements on the transportation of cylinders of 
compressed oxygen by aircraft and prohibited the carriage of chemical 
oxidizers in inaccessible aircraft cargo compartments that do not have 
a fire or smoke detection and fire suppression system, 64 FR 45388 
(Aug. 19, 1999).

    In the August 19, 1999 final rule (in Docket No. HM-224A), we 
(RSPA) amended the HMR to: (1) Allow a limited number of cylinders 
containing medical-use oxygen to be carried in the cabin of a 
passenger-carrying aircraft, 49 CFR 175.10(b); (2) limit the number of 
oxygen cylinders that may be carried as cargo in compartments that lack 
a fire suppression system and require that cylinders be stowed 
horizontally on the floor or as close as practicable to the floor of 
the cargo compartment or unit load device, 49 CFR 175.85(h) & (i); and 
(3) require each cylinder of compressed oxygen (in the passenger cabin 
or a cargo compartment) to be placed in an overpack or outer packaging 
that meets the performance criteria of Air Transport Association 
Specification 300 for Type I (ATA 300) shipping containers, 49 CFR 
172.102, special provision A52. Based on the comments submitted in that 
proceeding and our assessment of alternatives, RSPA did not adopt the 
proposal in the notice of proposed rulemaking in docket No. HM-224A to 
prohibit all transportation of compressed oxygen on passenger-carrying 
aircraft.
    Rigid ATA 300 shipping containers are resilient, durable packaging 
that provides protection from shock and vibration and can be reused for 
at least 100 round trips. In the preamble to the August 19, 1999 final 
rule, we explained that testing conducted by FAA indicated that the ATA 
300 container provides an ``incremental'' level of thermal protection 
for oxygen cylinders, by increasing the time before a cylinder exposed 
to a fire would release its contents. However, FAA's testing also 
indicated that the risk posed by a compressed oxygen cylinder in a 
cargo compartment can be further reduced, or even eliminated, if the 
cylinder is placed in an overpack or outer packaging that provides more 
thermal protection and flame resistence than the ATA 300 containers 
presently in use. Accordingly, we announced that we were ``considering 
a requirement that an oxygen cylinder may be carried in an inaccessible 
cargo compartment on an aircraft only when the cylinder is placed

[[Page 25471]]

in an outer packaging or overpack meeting certain flame penetration 
resistance, thermal protection, and integrity standards.'' 64 FR at 
45393.

II. Summary of This NPRM

    This rulemaking proposes requirements for such an outer packaging 
for the transportation of compressed oxygen cylinders and chemical 
oxygen generators aboard an aircraft because additional testing by FAA 
indicates that additional protection is necessary for both. The 
proposed flame penetration standards for this outer packaging are those 
contained in Part III of Appendix F to 14 CFR part 25 (Test Method to 
Determine Flame Penetration Resistance of Cargo Compartment Liners). 
This flame penetration standard specifies that the test specimen be 
exposed to a flame temperature of 1,700 [deg]F for five minutes. In 
order to pass the test there must be no flame penetration and the peak 
temperature 4 inches above the specimen must not exceed 400 [deg]F. The 
proposed thermal protection standards, to be added in Appendix D to 49 
CFR part 178, would specify that, when exposed to a temperature of at 
least 400 [deg]F for three hours, a cylinder must remain below the 
temperature at which its pressure relief device (PRD) would activate, 
and a chemical oxygen generator must not actuate. If the requirements 
for improved outer packagings are adopted, we would remove the present 
limitation on the number of cylinders of compressed oxygen that may be 
transported in a cargo compartment that is not equipped with a fire 
suppression system, in 49 CFR 175.85(i)(1) and (3).
    In addition, we are proposing to: (1) Revise the PRD setting on 
cylinders of compressed oxygen to better prevent a cylinder from 
releasing its contents when exposed to a fire; (2) limit the types of 
cylinders in which compressed oxygen may be transported aboard an 
aircraft to minimize the number of PRD settings; (3) prohibit the 
transportation of cylinders containing other oxidizing gases aboard 
passenger-carrying and cargo aircraft, because a fire in a cargo 
compartment could overcome a fire suppression system when intensified 
by these materials; and (4) incorporate into the HMR many of the 
current provisions RSPA includes in approvals authorizing the 
transportation of chemical oxygen generators aboard cargo-only 
aircraft.

III. Proposed Amendments to the HMR

A. Outer Packaging for Compressed Oxygen Cylinders and Oxygen 
Generators

    When installed on an aircraft or provided during flight for the use 
of passengers or crew members, compressed oxygen in cylinders and 
oxygen generators are subject to requirements in FAA's regulations in 
title 14 of the Code of Federal Regulations, and are not subject to the 
HMR. When transported as cargo, cylinders of compressed oxygen and 
oxygen generators are subject to requirements in the HMR. Air carriers 
routinely transport their own oxygen cylinders and oxygen generators as 
replacement items for use on other aircraft. Some also transport 
cylinders for their passengers or other customers. Commenters to Docket 
HM-224A identified a continuing need for the transportation of oxygen 
cylinders as cargo on both passenger and cargo-only aircraft.
    In testing conducted by FAA in 1999, cylinders of compressed oxygen 
released their contents at temperatures well below those that aircraft 
cargo compartment liners and structures are designed to withstand. When 
the surface temperature of a cylinder of compressed oxygen reaches 
approximately 300 [deg]F, the increase in internal pressure causes the 
cylinder's pressure relief device to open and release oxygen. If oxygen 
vents directly into a fire, it can significantly increase the risks 
posed by the fire. FAA also found that use of an outer packaging may 
significantly lengthen the time that a cylinder will retain its 
contents when exposed to fire or heat. Some outer packagings meeting 
the ATA specification Category I extended the time by up to 60 minutes 
or more. However, the ATA standard does not specifically address 
thermal protection or flame penetration. An outer packaging that is 
designed to provide both thermal protection and flame penetration could 
provide even more protection. A copy of the test report is available 
for review in the public docket.
    In additional tests conducted in 2002, FAA determined that a sodium 
chlorate oxygen generator will initiate and release oxygen at a minimum 
temperature of 600 [deg]F. However, due to uncertainties with other 
designs and the physical properties of sodium chlorate, the FAA has 
recommended that oxygen generators not be exposed to temperatures above 
400 F. A copy of this test report is also available in the public 
docket.
    An unprotected oxygen cylinder or oxygen generator can quickly and 
violently release its contents when exposed to temperatures that can be 
expected from an aircraft cargo compartment fire. Thus, we are 
proposing to require that cylinders of compressed oxygen and chemical 
oxygen generators be transported in an outer packaging that: (1) Meets 
the same flame penetration resistance standards as required for cargo 
compartment sidewalls and ceiling panels in transport category 
airplanes; and (2) provides certain thermal protection capabilities so 
as to retain its contents during an otherwise controllable cargo 
compartment fire. The outer packaging standard that is being proposed 
addresses two safety concerns: (1) Protecting a cylinder and a oxygen 
generator that could be exposed directly to flames from a fire; and (2) 
protecting a cylinder and a oxygen generator that could be exposed 
indirectly to heat from a fire. These performance requirements must 
remain in effect for the entire service life of the outer packaging.
    These regulations would require that an outer packaging for an 
oxygen cylinder and a package containing an oxygen generator meet the 
standards in Part III of Appendix F to 14 CFR Part 25, Test Method to 
Determine Flame Penetration Resistance of Cargo Compartment Liners. In 
order to comply with the requirements of the flame penetration 
resistance test, a flat 16 by 24 inch test specimen must be constructed 
that represents the outer package design. At least three specimens of 
outer packaging materials and each different design feature must be 
tested. Each specimen tested must simulate the outer packaging, 
including any design features, such as handles, latches, seams, hinges, 
etc., the failure of which would affect the capability of the outer 
packaging to prevent actuation of the oxygen cylinder pressure relief 
mechanisms or actuation of the oxygen generator. Each specimen must be 
placed in the horizontal ceiling position of the test apparatus, and 
must prevent flame penetration for a period of 5 minutes and the 
maximum allowable temperature at a point 4 inches above the test 
specimen, centered over the burner cone, may not exceed 400 [deg]F. 
Typically, the outer packaging closure mechanism, seam or hinges are 
tested independently in a longitudinal fashion, centered over the 
burner flame. See ``Burnthrough Test Procedures for Cargo Liner Design 
Features,'' DOT/FAA/CT-TN 88/33. Thus, an outer packaging's materials 
of construction would be required to prevent penetration by a

[[Page 25472]]

flame of 1,700 [deg]F for five minutes, in accordance with part III of 
appendix F paragraph (f)(5) of 14 CFR part 25.
    In addition, we propose to require that a cylinder of compressed 
oxygen remain below the temperature at which its pressure relief device 
would activate, and that an oxygen generator not actuate, when exposed 
to a temperature of at least 400 [deg]F for three hours. The 400 [deg]F 
temperature is the estimated mean temperature of a cargo compartment 
during a halon-suppressed fire.\1\ Three hours and 27 minutes is the 
maximum estimated diversion time for an aircraft flying a southern or 
oceanic route. Data collected during the FAA tests indicates that, on 
average, a 3AA oxygen cylinder with a pressure relief device (PRD) set 
at cylinder test pressure will open when the cylinder reaches a 
temperature of approximately 300 [deg]F. This result agrees with 
calculations performed by RSPA. In analyzing PRD function, RSPA 
calculated that a 3HT cylinder with a PRD set at 90% of cylinder test 
pressure will vent at temperatures greater than 220 [deg]F. In order to 
assure an adequate safety margin for all authorized cylinders, 
including 3HT cylinders, we are proposing that cylinders of compressed 
oxygen contained in an outer packaging not reach an external 
temperature of 93 [deg]C (199 [deg]F) when exposed to a 400 [deg]F 
temperature for three hours. A thermal resistance test for packagings 
for oxygen cylinders and oxygen generators would be added in appendix D 
to part 178.
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    \1\ The FAA is currently evaluating other non-ozone-depleting 
suppression agents that could eventually be used in cargo 
compartments. Some of these agents can maintain an adequate level of 
safety in the compartment, but the mean temperature may be slightly 
higher than 400 [deg]F, which is the level found during typical 
halon-suppressed fires. If an alternate agent is used, the oven soak 
temperature level may need to be adjusted accordingly.
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    In addition to meeting the flame penetration and thermal resistance 
protection requirements, we would continue to require that the outer 
packaging for compressed oxygen cylinders meet certain performance 
criteria. That requirement is currently based on ATA Specification 300. 
However, in order to provide greater flexibility in the design of these 
packagings, we are proposing to allow the outer packaging to be built 
either to the ATA Specification 300 standard or to a UN standard at the 
Packing Group II performance level. In addition, in order to clarify 
our original intent in adopting the ATA Specification 300, and in order 
to ensure an adequate level of safety, we are proposing to authorize 
only rigid outer packagings.
    Because of the added safety margin associated with these improved 
outer packagings, we are proposing to remove the limits in Sec.  
175.85(i) on the number of oxygen cylinders that may be transported in 
cargo compartments that are not equipped with fire/smoke detection and 
fire suppression systems. In addition, to provide industry with 
sufficient time to retrofit or replace existing outer packagings we 
propose an effective date of one year after publication of the final 
rule as the mandatory date to comply with the new thermal resistance 
and flame penetration resistance standards for outer packagings for 
oxygen cylinders and oxygen generators transported on board aircraft.
    Transport category airplane cargo compartments are classified under 
14 CFR 25.857. Classifications vary based on accessibility to 
crewmembers during flight and methods implemented to mitigate fire 
hazards (cargo liner, fire/smoke detection, fire suppression, and 
control of air flow). These compartments must meet the requirements of 
Sec. Sec.  25.855 and 25.858, as appropriate. There are no 
airworthiness standards pertaining to the classification of cargo 
compartments for other category airplanes certificated under 14 CFR.

B. Pressure Relief Device Settings and Authorized Cylinders for 
Compressed Oxygen

    In this NPRM, we are proposing a new limit on the pressure relief 
device settings on cylinders containing compressed oxygen when 
transported aboard aircraft. These changes will help ensure that the 
cylinder contents are not released into an aircraft cargo compartment 
in the event of a fire. In order to accomplish this, we must limit the 
PRD to a setting that will prevent it from releasing at temperatures 
that the cylinder will experience while protected by the outer 
packaging. PRD requirements for DOT specification cylinders are found 
in the Compressed Gas Association (CGA) Pamphlet S-1.1. On high 
pressure oxygen cylinders, the authorized PRD's are CG-4 and CG-5 
combination rupture disk/fusible plug devices, and CG-1 rupture disk 
devices. According to CGA Pamphlet S-1.1, the burst pressure of the 
disks must be no greater than the minimum cylinder test pressure. CGA 
Pamphlet S-1.1 does not set a lower burst limit on the disks; 
therefore, cylinders could be equipped with CG-1 rupture disks that 
could release product at any elevated temperature. RSPA believes the 
current CGA Pamphlet S-1.1 pamphlet requirements did not consider 
exposure of cylinders to aircraft cargo compartment fires. In this NPRM 
we propose that oxygen cylinders be equipped with PRD's that have a set 
pressure equal to cylinder test pressure with allowable tolerances of -
10 to plus zero percent. This is the same tolerance required by the CGA 
S-1.1 pamphlet for all rupture disks.
    Currently, in accordance with Sec.  173.302a(a)(2), DOT 3HT 
cylinders must be equipped with rupture disks that have a rated 
bursting pressure which does not exceed 90 percent of the cylinder test 
pressure. Under the current rule, there is no lower limit on the 
required PRD setting. The rupture disks for DOT 3HT cylinders are set 
at a lower pressure than for other cylinders because the DOT 3HT 
cylinder has a lower safety factor (ratio of burst to service pressure) 
than other seamless cylinders. For oxygen transported in DOT 3HT 
specification cylinders, we propose that the PRD have a rated burst 
pressure of 90% of the cylinder test pressure with allowable tolerances 
of -10 to plus zero percent.
    In a letter to RSPA, an industry representative states that for 
medical oxygen cylinders the common practice is for companies to use a 
PRD with the rated rupture disc burst pressure at the cylinder test 
pressure. The companies use the setting at test pressure rather than at 
a lower pressure in order to prevent losing product through an early 
release of the PRD. In most cases, the proposed PRD setting at 100% of 
test pressure will not impose a burden on the industry. RSPA 
understands that there may be circumstances for which the new 
requirement may result in a burden. Comments are requested from 
companies that may be affected by this proposal.
    In this NPRM, we are also proposing that the cylinders authorized 
for the transportation of compressed oxygen aboard aircraft be limited 
to DOT specifications 3A, 3AA, 3AL, and 3HT. According to the 
information available to RSPA at this time, these are the most commonly 
used cylinders for this service. In some cases, such as the DOT 
specification 39 cylinder, the PRD setting requirements are different 
than for the most commonly used cylinders. To avoid a situation where 
there are numerous PRD setting requirements for oxygen cylinders aboard 
aircraft, we propose to limit the authorized cylinders to the four 
specifications listed above.

C. Other Oxidizing Gases Aboard Aircraft

    We are also proposing to prohibit the transportation of all 
oxidizing gases,

[[Page 25473]]

except compressed oxygen, aboard cargo and passenger aircraft. These 
affected materials are covered under the shipping descriptions ``Air, 
refrigerated liquid, (cryogenic liquid),'' ``Carbon dioxide and oxygen 
mixtures, compressed,'' ``Nitrous oxide,'' ``Nitrogen trifluoride, 
compressed'', ``Compressed gas, oxidizing, n.o.s.,'' and ``Liquified 
gas, oxidizing, n.o.s.'' We believe that cylinders of these oxidizing 
gases could also, if exposed to a fire, intensify a fire to the extent 
that the fire could overcome the compartment's halon fire suppression 
system and cause severe damage to the aircraft. However, unlike 
compressed oxygen, we have no information to support the need to allow 
these materials to continue to be transported aboard aircraft.

D. Chemical Oxygen Generator Approval

    The June 5, 1997, final rule under Docket HM-224A amended the HMR 
by (1) adding a specific shipping description to the Hazardous 
Materials Table for chemical oxygen generators; and (2) requiring 
approval of a chemical oxygen generator, and its packaging, when the 
chemical oxygen generator is to be transported, by any mode, with its 
means of initiation attached. There are currently over 180 holders of 
the chemical oxygen generator approval. (62 FR 30767) We now believe 
that those aspects of the approval that deal with safety controls, 
packaging and marking can be incorporated into the HMR, thus 
eliminating the need for many persons to be holders of the approval. We 
will still require approval of a chemical oxygen generator; however, 
this approval process would be limited to those persons who manufacture 
oxygen generators and not distributors or persons who re-ship them. 
Therefore, we are proposing to add a new Sec.  173.168 that would 
specify: (1) The number and type of means that must be incorporated 
into an oxygen generator design in order to prevent actuation; (2) that 
the oxygen generator must be capable of withstanding a 1.8 meter drop 
with no loss of contents or actuation; (3) packaging requirements; (4) 
shipping paper requirements; and (5) marking requirements for those 
oxygen generators that are installed in a piece of equipment which is 
sealed or otherwise difficult to determine if an oxygen generator is 
present. In addition, we are proposing to specify in the HMR that a 
chemical oxygen generator that has past the manufacturer's expiration 
date is forbidden for transportation by aircraft. Through the approval 
process, RSPA had not allowed the transportation of expired oxygen 
generators aboard aircraft. With the elimination of the approval, for 
other than oxygen generator manufactures, we believe it is now 
necessary to specify this restriction in the HMR.

IV. Effects on Individuals With Disabilities

    Under separate RSPA and FAA rules [49 CFR 175.10(a)(7), and 14 CFR 
121.574 and 135.91, respectively], which this proposal would not amend, 
passengers may not carry their own oxygen aboard aircraft for use 
during flight. Air carriers are permitted to provide oxygen for 
passenger use in accordance with specified requirements in the 
aforementioned rules, although some air carriers may choose not to 
provide this service for their passengers. RSPA seeks comment on 
whether the new proposed provisions placed on carriage of air carriers' 
own oxygen cylinders will significantly interfere with carriers' 
ability to provide this service, or increase the costs of this service, 
to passengers.
    The Office of the Secretary, RSPA and FAA have initiated a project 
separate from this rulemaking action to explore whether safe 
alternatives exist for accommodating passenger needs in regard to use 
of medical oxygen. This project may result in proposals to amend the 
relevant portions of the HMR and FAA regulations, as well as those of 
the Office of the Secretary implementing the Air Carrier Access Act of 
1986 (49 U.S.C. 41705), which prohibits discrimination in regard to air 
traveler access on the basis of disability.

V. Request for Comments

    We ask you to address the following questions, to the extent you 
are able, in your comments on the proposals in this NPRM:
    1. How well do the test protocols followed by FAA approximate the 
conditions of real-life incidents?
    2. How many different types of outer packagings meeting the 
proposed thermal resistance and flame penetration resistance 
requirements would be needed for oxygen service and/or oxygen generator 
service? How many outer packagings of each type would be needed?
    3. Are the cylinders in service sufficiently uniform to permit 
development of a limited number of standardized outer packagings?
    4. Is it practical to retrofit existing outer packagings and what 
would be the costs of the retrofit?
    5. What would be the estimated cost for an outer packaging that 
meets the proposed thermal and flame penetration resistance 
requirements? What is the average cost of currently used outer 
packagings?
    6. Are there other means of providing an equivalent level of safety 
that RSPA should consider in formulating a final rule?
    7. Will the one-year implementation date provide sufficient time 
for development, manufacture, and staging of the proposed outer 
packagings? Can the proposed regulation be implemented over a shorter 
time period?
    8. Should the HMR incorporate different outer packaging standards 
based on the type of cargo compartment in which the cylinder will be 
transported? What should those standards be?
    9. Should the HMR incorporate different outer packaging standards 
based on whether transport is on passenger or cargo aircraft? What 
should the exposure temperature capability be?
    10. Should an exposure temperature greater than 400 [deg]F be used 
for the thermal resistance test to accommodate variance in fire 
suppression agents? What should the temperature be?
    11. How many cylinders would be affected by the proposal to require 
pressure relief devices to have a rated burst pressure of the cylinder 
test pressure minus 10%, plus 0%? What would be the cost of this 
requirement?
    12. Should the flame penetration standard, currently contained in 
14 CFR part 25 be incorporated by reference into the HMR or should it 
be duplicated in the HMR?
    13. Is there a need for other oxidizing gases to be transported 
aboard an aircraft? Which gases? What performance standards should 
apply to outer packagings for such gases?
    14. Will the costs imposed by this rulemaking cause you, an airline 
operator, to discontinue providing oxygen service to persons with 
disabilities?
    15. Will this proposal increase the current charges that are 
imposed on persons needing supplemental oxygen during flight? If so, 
what will be the increase in the fee?

VI. Regulatory Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and Procedures

    This proposed rule, if adopted, would be considered a significant 
regulatory action under section 3(f) of Executive Order 12866 and, 
therefore, was reviewed by the Office of Management and Budget. This 
rule would also be significant under the Regulatory Policies and 
Procedures of the Department of Transportation (44 FR 11034). A copy of 
the preliminary regulatory evaluation is

[[Page 25474]]

available for review in the public docket.

B. Executive Order 13132

    This proposed rule has been analyzed in accordance with the 
principles and criteria contained in Executive Order 13132 
(``Federalism''). This proposed rule would preempt State, local and 
Indian tribe requirements, but does not propose any regulation that has 
direct effects on the States, the relationship between the national 
government and the States, or the distribution of power and 
responsibilities among the various levels of government. Therefore, the 
consultation and funding requirements of Executive Order 13132 do not 
apply.
    The Federal hazardous materials transportation law, 49 U.S.C. 5101-
5127, contains an express preemption provision (49 U.S.C. 5125(b)) that 
preempts State, local, and Indian tribe requirements on certain covered 
subjects. Covered subjects are:
    (1) The designation, description, and classification of hazardous 
materials;
    (2) The packing, repacking, handling, labeling, marking, and 
placarding of hazardous materials;
    (3) The preparation, execution, and use of shipping documents 
related to hazardous materials and requirements related to the number, 
contents, and placement of those documents;
    (4) The written notification, recording, and reporting of the 
unintentional release in transportation of hazardous material; and
    (5) The design, manufacture, fabrication, marking, maintenance, 
recondition, repair, or testing of a packaging or container 
represented, marked, certified, or sold as qualified for use in 
transporting hazardous material.
    This proposed rule addresses item 5 above and would preempt any 
State, local, or Indian tribe requirements not meeting the 
``substantially the same'' standard.
    Federal hazardous materials transportation law provides at Sec.  
5125(b)(2) that, if DOT issues a regulation concerning any of the 
covered subjects, DOT must determine and publish in the Federal 
Register the effective date of Federal preemption. The effective date 
may not be earlier than the 90th day following the date of issuance of 
the final rule and not later than two years after the date of issuance. 
RSPA proposes that the effective date of Federal preemption will be 90 
days from publication of a final rule in this matter in the Federal 
Register.

C. Executive Order 13175

    This proposed rule has been analyzed in accordance with the 
principles and criteria contained in Executive Order 13175 
(``Consultation and Coordination with Indian Tribal Governments''). 
Because this proposed rule, if adopted, would not have tribal 
implications and does not impose direct compliance costs, the funding 
and consultation requirements of Executive Order 13175 do not apply.

D. Regulatory Flexibility Act

    The Regulatory Flexibility Act of 1980 establishes ``as a principle 
of regulatory issuance that agencies shall endeavor, consistent with 
the objective of the rule and of applicable statutes, to fit regulatory 
and informational requirements to the scale of the business, 
organizations, and governmental jurisdictions subject to regulation.'' 
To achieve that principal, the Act requires agencies to solicit and 
consider flexible regulatory proposals and to explain the rationale for 
their actions. The Act covers a wide-range of small entities, including 
small businesses, not-for-profit organizations and small governmental 
jurisdictions.
    Agencies must perform a review to determine whether a proposed or 
final rule will have a significant economic impact on a substantial 
number of small entities. If the determination is that it will, the 
agency must prepare a regulatory flexibility analysis (RFA) as 
described in the Act.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the 1980 Act provides that 
the head of the agency may so certify and an RFA is not required. The 
certification must include a statement providing the factual basis for 
this determination, and the reasoning should be clear.
    The Small Business Administration recommends that ``small'' 
represent the impacted entities with 1,500 or fewer employees. For this 
proposed rule, small entities are part 121 and part 135 air carriers 
with 1,500 or fewer employees that are approved to carry hazardous 
materials. DOT identified 729 air carriers that meet this definition. 
DOT contacted several of these entities to estimate the number of 
containers that each small air carrier uses to transport oxygen 
cylinders aboard aircraft in other than the passenger cabin. From 
conversations with container manufacturers, DOT learned that 
approximately ten small air carriers transport compressed oxygen 
cylinders. DOT also believes that each of the ten small air carriers 
would need approximately 5 compressed oxygen containers to comply with 
the proposed rule. DOT also estimates that each of ten small carriers 
would need approximately 5 oxygen generator containers to comply with 
the proposed rule.

                                  Table 2.--Incremental Costs per Small Entity
----------------------------------------------------------------------------------------------------------------
                                                                                      Capital
                      Cost per small entity                        NPV of costs      recovery       Annualized
                                                                   over 15 years      factor           costs
----------------------------------------------------------------------------------------------------------------
Baseline Costs..................................................          $2,937         0.10979            $322
Proposed Costs..................................................          10,104         0.10979           1,109
Incremental Costs...............................................           7,167         0.10979             787
----------------------------------------------------------------------------------------------------------------

    After calculating the prorated annualized costs per entity using 
the same assumptions that were used in the cost section, the DOT has 
determined that the incremental cost impact per small entity would be 
$787 (Table 2), which RSPA considers is ``de minimus'' for a small 
business (See the regulatory evaluation in the public docket). The 
baseline costs per small entity shown in Table 2 are generated from 
appendix C by adding the baseline discounted costs of oxygen cylinders 
and chemical oxygen generator overpacks. Similarly, proposed costs in 
Table 2 are generated by adding discounted costs of the proposed rule 
for oxygen cylinder and chemical oxygen generator overpacks in Table 2. 
Annualized costs are calculated by applying a capital recovery factor 
to total incremental costs.
    Besides small airlines, there may also be small entities that are 
distributors or other types of companies that transport oxygen 
cylinders and/or chemical oxygen generators on aircraft. DOT does not 
believe that any other small entities transport oxygen cylinders. 
However

[[Page 25475]]

there may be small entities besides airlines that distribute on 
airlines chemical oxygen generators and will be affected by this rule. 
RSPA welcomes cost information from these small entities.
    Thus, RSPA has determined that this proposed rule would not have a 
significant impact on a substantial number of small entities. RSPA 
calls for comments on this analysis.

E. Unfunded Mandates Reform Act of 1995

    This proposed rule, if adopted, would not impose unfunded mandates 
under the Unfunded Mandates Reform Act of 1995. It would not result in 
costs of $100 million or more, in the aggregate, to any of the 
following: State, local, or Native American tribal governments, or the 
private sector. This NPRM is the least burdensome alternative that 
achieves the objective of the rule.

F. Paperwork Reduction Act

    This proposed rule may result in an information collection and 
recordkeeping burden increase under OMB Control Number 2137-0572, due 
to proposed changes in package design and testing requirements for 
compressed oxygen and oxygen generators. There will be an editorial 
change with no change in burden under OMB Control Number 2137-0557, due 
to proposed changes in section designations regarding approval 
requirements for oxygen generators. RSPA currently has an approved 
information collection under OMB Control Number 2137-0557, ``Approvals 
for Hazardous Materials'' with 25,605 burden hours which expires on 
December 31, 2005, and OMB Control Number 2137-0572, ``Testing 
Requirements for Non-Bulk Packaging'' with 30,000 burden hours which 
expires on September 30, 2004.
    Section 1320.8(d), title 5, Code of Federal Regulations requires 
that RSPA provide interested members of the public and affected 
agencies an opportunity to comment on information collection and 
recordkeeping requests. This notice identifies a new information 
collection request that RSPA will submit to OMB for approval based on 
the requirements in this proposed rule.
    RSPA has developed revised burden estimates to reflect changes in 
this proposed rule. RSPA estimates that, based on the proposals to in 
this rule, the current information collection burden for ``Testing 
Requirements for Non-Bulk Packaging'' will be as follows: ``Testing 
Requirements for Non-Bulk Packaging''
    OMB Number: 2137-0572.
    Total Annual Number of Respondents: 5,010.
    Total Annual Responses: 15,500.
    Total Annual Burden Hours: 32,500.
    Total Annual Burden Cost: $812,500.00.
    Requests for a copy of this information collection should be 
directed to Deborah Boothe or T. Glenn Foster, Office of Hazardous 
Materials Standards (DHM-10), Research and Special Programs 
Administration, Room 8422, 400 Seventh Street, SW., Washington, DC 
20590-0001, Telephone (202) 366-8553.
    Written comments should be addressed to the Dockets Unit as 
identified in the ADDRESSES section of this rulemaking. We must receive 
comments regarding information collection burdens prior to the close of 
the comment period identified in the DATES section of this rulemaking. 
Under the Paperwork Reduction Act of 1995, no person is required to 
respond to an information collection unless it displays a valid OMB 
control number.

G. Environmental Assessment

    The National Environmental Policy Act of 1969 (NEPA), as amended 
(42 U.S.C. 4321-4347) requires Federal agencies to consider the 
consequences of major Federal actions and prepare a detailed statement 
on actions significantly affecting the quality of the human 
environment. RSPA developed an assessment to consider the effects of 
these revisions on the environment and determine whether a more 
comprehensive environmental impact statement may be required. We have 
tentatively concluded that there are no significant environmental 
impacts associated with this proposed rule. Interested parties, 
however, are invited to review the Preliminary Environmental Assessment 
available in the docket and to comment on what environmental impact, if 
any, the proposed regulatory changes would have.

H. Regulation Identifier Number (RIN)

    A regulation identifier number (RIN) is assigned to each regulatory 
action listed in the Unified Agenda of Federal Regulations. The 
Regulatory Information Service Center publishes the Unified Agenda in 
April and October of each year. The RIN number contained in the heading 
of this document can be used to cross-reference this action with the 
Unified Agenda.

I. Privacy Act

    Anyone is able to search the electronic form of all comments 
received into any of our dockets by the name of the individual 
submitting the comment (or signing the comment, if submitted on behalf 
of an association, business, labor union, etc.). You may review DOT's 
complete Privacy Act Statement in the Federal Register published on 
April 11, 2000 (Volume 65, Number 70; Pages 19477-78) or you may visit 
http://dms.dot.gov.

J. International Trade Impact Assessment

    The Trade Agreement Act of 1979 prohibits Federal agencies from 
engaging in any standards or related activities that create unnecessary 
obstacles to the foreign commerce of the United States. Legitimate 
domestic objectives, such as safety, are not considered unnecessary 
obstacles. The statute also requires consideration of international 
standards and where appropriate, that they be the basis for U.S. 
standards.
    The proposed rule is not expected to affect trade opportunities for 
U.S. firms doing business overseas or for foreign firms doing business 
in the United States. Furthermore, the proposed rule is consistent with 
the terms of several trade agreements to which the United States is a 
signatory, such as the Trade Agreement Act of 1979 (19 U.S.C. 2501 et 
seq.), incorporating the Agreement on Trade in Civil Aircraft (31 
U.S.T. 619) and the Agreement on Technical Barriers to Trade 
(Standards) (19 U.S.C. 2531). The proposed rule is also consistent with 
49 U.S.C. 40105, formerly 1102 (a) of the Federal Aviation Act of 1958, 
as amended, which requires the RSPA to exercise and perform its powers 
and duties consistently with any obligation assumed by the United 
States in any agreement that may be in force between the United States 
and any foreign country or countries.

List of Subjects

49 CFR Part 171

    Exports, Hazardous materials transportation, Hazardous waste, 
Imports, Reporting and recordkeeping requirements.

49 CFR Part 172

    Education, Hazardous materials transportation, Hazardous waste, 
Labeling, Markings, Packaging and containers, Reporting and 
recordkeeping requirements.

49 CFR Part 173

    Hazardous materials transportation, Packaging and containers, 
Radioactive materials, Reporting and recordkeeping requirements, 
Uranium.

[[Page 25476]]

49 CFR Part 175

    Air Carriers, Hazardous materials transportation, Radioactive 
materials, Reporting and recordkeeping requirements.

49 CFR Part 178

    Hazardous materials transportation, Motor vehicle safety, Packaging 
and containers, Reporting and recordkeeping requirements.
    In consideration of the foregoing, we propose to amend 49 CFR 
chapter I as follows:

PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS

    1. The authority citation for part 171 is revised to read as 
follows:

    Authority: 49 U.S.C. 5101-5127; 44701; 49 CFR 1.53.

    2. In Sec.  171.11, paragraph (d)(16) is revised to read as 
follows:


Sec.  171.11  Use of ICAO Technical Instructions.

* * * * *
    (d) * * *
    (16) A package containing Oxygen, compressed, must be packaged as 
required by Parts 173 and 178 of this subchapter.
* * * * *

PART 172--HAZARDOUS MATERIALS TABLE, SPECIAL PROVISIONS, HAZARDOUS 
MATERIALS COMMUNICATIONS, EMERGENCY RESPONSE INFORMATION, AND 
TRAINING REQUIREMENTS

    3. The authority citation for part 172 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.


Sec.  172.101  [Amended]

    4. In the Hazardous Materials Table in Sec.  172.101, for the 
shipping name ``Air, refrigerated liquid, (cryogenic liquid),'' Column 
(9B) is revised to read ``Forbidden.''
    5. In the Hazardous Materials Table in Sec.  172.101, for the 
shipping names ``Carbon dioxide and oxygen mixtures, compressed,'' 
``Compressed gas, oxidizing, n.o.s.,'' ``Liquified gas, oxidizing, 
n.o.s.,'' ``Nitrogen trifluoride,'' and ``Nitrous Oxide,'' Columns (9A) 
and (9B) are revised to read ``Forbidden,''.
    5a. In the Hazardous Materials Table in Sec.  172.101, for the 
shipping name ``Oxygen, compressed'', in column (7), Special Provision 
``A52'' is removed.
    6. In the Hazardous Materials Table in Sec.  172.101, for the 
shipping name ``Oxygen generator, chemical,'' in Column (7), Special 
Provisions ``60, A51'' is removed and Column (8B) is revised to read 
``168.''


Sec.  172.102  [Amended]

    7. In Sec.  172.102, in paragraph (c)(1), Special Provisions ``60'' 
is removed.
    8. In Sec.  172.102, in paragraph (c)(2), Special Provisions 
``A51'' and ``A52'' are removed.

PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND 
PACKAGINGS

    9. The authority citation for part 173 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127, 44701; 49 CFR 1.45, 1.53.

    10. Section 173.168 is added to read as follows:


Sec.  173.168  Chemical oxygen generators.

    An oxygen generator, chemical (defined in Sec.  171.8 of this 
subchapter) may be transported only under the following conditions:
    (a) Approval. A chemical oxygen generator that is shipped with a 
means of initiation attached must be classed and approved by the 
Associate Administrator for Hazardous Materials Safety in accordance 
with the procedures specified in Sec.  173.56 of this subchapter. The 
approval number must be placed on the shipping paper, in association 
with the basic description required by Sec.  172.202(a) of this 
subchapter, required to accompany a chemical oxygen generator in 
transportation.
    (b) Impact resistance. A chemical oxygen generator, without any 
packaging, must be capable of withstanding a 1.8 meter drop onto a 
rigid, non-resilient, flat and horizontal surface, in the position most 
likely to cause damage, actuation or loss of contents.
    (c) Protection against inadvertent activation. A chemical oxygen 
generator must incorporate one of the following means of preventing 
inadvertent actuation:
    (1) For a chemical oxygen generator that is not installed in 
protective breathing equipment (PBE):
    (i) Mechanically actuated devices:
    (A) Two pins, installed so that each is independently capable of 
preventing the actuator from striking the primer;
    (B) One pin and one retaining ring, each installed so that each is 
independently capable of preventing the actuator from striking the 
primer; or
    (C) A cover securely installed over the primer and a pin installed 
so as to prevent the actuator from striking the primer and cover.
    (ii) Electrically actuated devices: The electrical leads must be 
mechanically shorted and the mechanical short must be shielded in metal 
foil.
    (iii) Devices with a primer but no actuator: A chemical oxygen 
generator that has a primer but no actuating mechanism must have a 
protective cover over the primer to prevent actuation from external 
impact.
    (2) A chemical oxygen generator installed in a PBE must contain a 
pin installed so as to prevent the actuator from striking the primer, 
and be placed in a protective bag, pouch, case or cover such that the 
protective breathing equipment is fully enclosed in such a manner that 
the protective bag, pouch, case or cover prevents unintentional 
actuation of the oxygen generator.
    (d) Packaging. A chemical oxygen generator and a chemical oxygen 
generator installed in equipment, (e.g., a PBE) must be placed in a 
rigid packaging that--
    (1) Conforms to the requirements of either:
    (i) Part 178, subparts L and M, of this subchapter at the Packing 
Group I or II performance level; or
    (ii) The performance criteria in Air Transport Association (ATA) 
Specification No. 300 for a Category I Shipping Container.
    (2) With its contents, is capable of meeting the following 
additional requirements when transported by cargo-only aircraft:
    (i) The Flame Penetration Resistance Test in Part III of Appendix F 
to 14 CFR Part 25, modified as follows:
    (A) At least three specimens of the outer packaging materials must 
be tested;
    (B) Each test must be conducted on a flat 16 inch x 24 inch test 
specimen mounted in the horizontal ceiling position of the test 
apparatus to represent the outer packaging design;
    (C) Testing must be conducted on all design features (latches, 
seams, hinges, etc.) affecting the ability of the overpack to safely 
prevent the passage of fire in the horizontal ceiling position; and
    (D) There must be no flame penetration of any specimen within 5 
minutes after application of the flame source and the maximum allowable 
temperature at a point 4 inches above the test specimen, centered over 
the burner cone must not exceed 205 [deg]C (400 [deg]F).
    (ii) The Thermal Resistance Test specified in Appendix D to part 
178 of this subchapter.
    (iii) Prevents all of the following conditions from occurring when 
one generator in the package is actuated:

[[Page 25477]]

    (A) Actuation of other generators in the package;
    (B) Ignition of the packaging materials; and
    (C) A temperature above 100 [deg]C (212 [deg]F) on the outside 
surface temperature of the package.
    (iv) Has all its features in good condition, including all latches, 
hinges, seams, and other features, and is free from perforations, 
cracks, dents, or other abrasions that may negatively affect the flame 
penetration resistance and thermal resistance, verified by a visual 
inspection of the package before each shipment.
    (e) Equipment marking. The outside surface of a chemical oxygen 
generator must be marked to indicate the presence of an oxygen 
generator (e.g., ``oxygen generator, chemical''). The outside surface 
of equipment containing a chemical oxygen generator that is not readily 
apparent (e.g., a sealed passenger service unit) must be clearly marked 
to indicate the presence of the oxygen generator (example: ``Oxygen 
Generator Inside'').
    (f) Items forbidden in air transportation.
    (1) A chemical oxygen generator is forbidden for transportation on 
board a passenger-carrying aircraft.
    (2) A chemical oxygen generator is forbidden for transportation by 
both passenger-carrying and cargo-only aircraft after (i) the 
manufacturer's expiration date, or (ii) the contents of the generator 
have been expended.
    11. In Sec.  173.302a, paragraph (e) is added to read as follows:


Sec.  173.302a  Additional requirements for shipment of nonliquefied 
(permanent) compressed gases in specification cylinders.

* * * * *
    (e) Oxygen, compressed. A cylinder containing compressed oxygen is 
authorized for transportation by aircraft only when it meets the 
following requirements:
    (1) Only DOT specification 3A, 3AA, 3AL, and 3HT cylinders are 
authorized.
    (2) Cylinders must be equipped with a pressure relief device (PRD) 
in accordance with Sec.  173.301(f) except that the rated burst 
pressure of a rupture disc for DOT 3A, 3AA, and 3AL cylinders must be 
100% of the cylinder minimum test pressure and DOT 3HT cylinders must 
be equipped with a rupture disc type PRD only. The allowable tolerance 
of a PRD must be -10 to zero percent of the cylinder minimum test 
pressure.
    (3) The cylinder must be placed in a rigid outer packaging that--
    (i) Conforms to the requirements of part 178 of this subchapter at 
the Packing Group I or II performance level or to the performance 
criteria in Air Transport Association (ATA) Specification 300 for a 
Category I Shipping Container;
    (ii) Is capable of passing, as demonstrated by design testing, the 
Flame Penetration Resistance Test in Part III of Appendix F to 14 CFR 
Part 25, modified as follows:
    (A) At least three specimens of oxygen cylinder outer packaging 
materials must be tested;
    (B) Each test must be conducted on a flat 16 inch x 24 inch test 
specimen mounted in the horizontal ceiling position of the test 
apparatus to represent the overpack design;
    (C) Testing must be conducted on all design features (latches, 
seams, hinges, etc.) affecting the ability of the overpack to safely 
prevent the passage of fire in the horizontal ceiling position; and
    (D) There must be no flame penetration of any specimen within 5 
minutes after application of the flame source and the maximum allowable 
temperature at a point 4 inches above the test specimen, centered over 
the burner cone must not exceed 205 [deg]C (400 [deg]F); and
    (iii) Prior to each shipment, passes a visual inspection that 
verifies that all features of the packaging are in good condition, 
including all latches, hinges, seams, and other features, and is free 
from perforations, cracks, dents, or other abrasions that may 
negatively affect the flame penetration resistance and thermal 
resistance performance characteristics of the container.
    (4) The cylinder and the outer packaging must be capable of 
passing, as demonstrated by design testing, the Thermal Resistance Test 
specified in Appendix D to part 178 of this subchapter.
    (5) The cylinder and the outer packaging must both be marked and 
labeled in accordance with part 172, subparts D and E of this 
subchapter.
    (6) A cylinder of compressed oxygen that has been furnished by an 
aircraft operator to a passenger in accordance with 14 CFR 121.574 is 
excepted from the outer packaging requirements of paragraph (e)(3).

PART 175--CARRIAGE BY AIRCRAFT

    12. The authority citation for part 175 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.

    13. In Sec.  175.10, paragraphs (b)(2), (b)(3) and (b)(5)(i) are 
revised to read as follows:


Sec.  175.10  Exceptions.

* * * * *
    (b) * * *
    (2) The rated capacity of each cylinder may not exceed 1,000 L (34 
cubic feet);
    (3) Each cylinder must conform to the provisions of this subchapter 
and be placed in:
    (i) An outer packaging that conforms to the performance criteria of 
Air Transport Association (ATA) Specification 300 for a Category I 
Shipping Container; or
    (ii) A metal, plastic or wood outer packaging that conforms to a UN 
standard at the Packing Group II performance level.
* * * * *
    (5) * * *
    (i) Section 173.302(e) of this subchapter, subpart C of part 172 of 
this subchapter, and, for passengers only, subpart H of part 172 of 
this subchapter.
* * * * *
    14. In Sec.  175.85, paragraph (h) is revised and paragraph (i) is 
removed to read as follows:


Sec.  175.85  Cargo location.

* * * * *
    (h) Except for Oxygen, compressed, no person may load or transport 
a hazardous material for which an OXIDIZER label is required under this 
subchapter in an inaccessible cargo compartment that does not have a 
fire or smoke detection system and a fire suppression system.

PART 178--SPECIFICATIONS FOR PACKAGINGS

    15. The authority citation for part 178 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.

    16. A new appendix D to part 178 is added to read as follows:

Appendix D to Part 178--Thermal Resistance Test

    1. Scope. This test method evaluates the thermal resistance 
capabilities of an outer packaging for a cylinder of compressed 
oxygen and an oxygen generator. When exposed to a temperature of 205 
[deg]C ( 400 [deg]F) for a period of not less than three hours, the 
outer surface of the enclosed cylinder may not exceed a temperature 
of 93 [deg]C (199 [deg]F) and the enclosed oxygen generator must not 
actuate.
    2. Apparatus.
    2.1 Test Oven. The oven must be large enough in size to fully 
house the test outer package without clearance problems. The test 
oven must be capable of reaching a minimum steady state temperature 
of 205 [deg]C (400 [deg]F) and must be capable of raising the 
temperature at a rate no less than 28 [deg]C (50 [deg]F) per minute.

[[Page 25478]]

    2.2 Thermocouples. At least three thermocouples must be used to 
monitor the temperature inside the oven and an additional three 
thermocouples must be used to monitor the temperature of the 
cylinder. The thermocouples must be \1/16\ inch, ceramic packed, 
metal sheathed, type K (Chromel-Alumel), grounded junction with a 
nominal 30 American wire gauge (AWG) size conductor. The 
thermocouples measuring the temperature inside the oven must be 
placed at varying heights to ensure even temperature and proper 
heat-soak conditions. For the thermocouples measuring the 
temperature of the cylinder: (1) two of them must be placed on the 
outer cylinder side wall at approximately 2 inches (5cm) from the 
top and bottom shoulders of the cylinder; and (2) one must be placed 
on the cylinder valve body near the pressure relief device.
    2.3 Instrumentation. A calibrated recording device or a 
computerized data acquisition system with an appropriate range 
should be provided to measure and record the outputs of the 
thermocouples.
    3. Test Specimen.
    3.1 Specimen Configuration. Each outer package material type and 
design must be tested, including any features such as handles, 
latches, fastening systems, etc., that may compromise the ability of 
the outer package to provide thermal protection.
    3.2 Test Specimen Mounting. The tested outer package must be 
supported at the four corners using fire brick or other suitable 
means. The entire bottom surface of the outer package must be 
exposed to allow exposure to heat.
    4. Preparation for Testing.
    4.1 The cylinder must be empty of all gas and configured as when 
filled with a valve and pressure relief device. The oxygen generator 
must be filled and packaged in the manner that it will be 
transported.
    4.2 Place the package onto supporting bricks or a stand inside 
the test oven, making certain that suitable clearance is available 
on all sides of the outer package.
    4.3 Pass the thermocouple wires through an access port in the 
test oven to the appropriate data collection apparatus to 
continuously monitor the oven temperature.
    5. Test Procedure.
    5.1 Close oven door and check for proper reading on 
thermocouples.
    5.2 Raise the temperature of the oven at a rate no less than 28 
[deg]C (50 [deg]F) per minute to a minimum temperature of 205 [deg]C 
(400 [deg]F). Maintain a minimum oven temperature of 205 [deg]C (400 
[deg]F) for at least three hours. Exposure time begins when the oven 
steady state temperature reaches a minimum of 205 [deg]C (400 
[deg]F).
    5.3 At the conclusion of the three-hour period, the outer 
package may be removed from the oven and allowed to cool naturally.
    6. Report.
    6.1 Report a complete description of the material being tested, 
including the manufacturer, size of cylinder, etc.
    6.2 Record any observations regarding the behavior of the test 
specimen during exposure, such as smoke production, delamination, 
resin ignition, and time of occurrence of each event.
    6.3 Report the temperature and time history of the cylinder 
temperature during the entire test for each thermocouple location. 
Temperature measurements must be recorded at intervals of not more 
than five (5) minutes. Report the maximum temperatures achieved at 
all three thermocouple locations and the corresponding time.
    7. Requirements.
    7.1 For a cylinder, the outer package must provide adequate 
protection such that the outer surface of the cylinder and valve 
does not exceed a temperature of 93[deg]C (199[deg]F ) at any of the 
three points where the thermocouples are located.
    7.2 For an oxygen generator, the outer packaging must provide 
adequate protection such that the oxygen generator does not actuate.

    Issued in Washington, DC, on April 28, 2004, under authority 
delegated in 49 CFR part 106.
Robert A. McGuire,
Associate Administrator for Hazardous Materials Safety.

[FR Doc. 04-10277 Filed 5-5-04; 8:45 am]
BILLING CODE 4910-60-P