[Federal Register Volume 62, Number 161 (Wednesday, August 20, 1997)]
[Proposed Rules]
[Pages 44374-44384]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-21739]


      

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Part V





Department of Transportation





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Research and Special Programs Administration



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49 CFR Parts 171, 172, and 175



Prohibition of Oxidizers Aboard Aircraft; Proposed Rule

Federal Register / Vol. 62, No. 161 / Wednesday, August 20, 1997 / 
Proposed Rules

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DEPARTMENT OF TRANSPORTATION

Research and Special Programs Administration

49 CFR Parts 171, 172, and 175

[Docket No. HM-224A; Notice No. 97-8]
RIN 2137-AC92


Prohibition of Oxidizers Aboard Aircraft

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

ACTION: Supplemental notice of proposed rulemaking.

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SUMMARY: On December 30, 1996, RSPA proposed to amend the Hazardous 
Material Regulations to prohibit the carriage of oxidizers, including 
compressed oxygen, aboard all passenger-carrying aircraft. The effect 
of this prohibition would be to limit oxidizers to accessible locations 
on cargo aircraft. The December 30, 1996 notice of proposed rulemaking 
analyzed Class D cargo compartments and indicated that a supplemental 
notice would be published to analyze Class B and C compartments. This 
supplemental notice specifically analyzes the prohibition of oxidizers 
in other than Class D cargo compartments. The proposed requirements 
would apply to foreign and domestic aircraft entering, leaving, or 
operating within the United States. The purpose of these proposals is 
to enhance air transportation safety.

DATES: Comments must be received by October 20, 1997.

ADDRESSES: Address comments to the Dockets Unit, Research and Special 
Programs Administration, U.S. Department of Transportation, room 8421, 
400 Seventh Street, SW., Washington, DC 20590-0001. Comments should 
identify the docket number and be submitted in five copies. Persons 
wishing to receive confirmation of receipt of their comments should 
include a self-addressed, stamped postcard. The Dockets Unit is located 
in the Department of Transportation headquarters building (Nassif 
Building) at the above address on the eighth floor. Public dockets may 
be reviewed there between the hours of 8:30 a.m. and 5:00 p.m., Monday 
through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Diane LaValle, Office of Hazardous 
Materials Standards, (202) 366-8553, Research and Special Programs 
Administration, U.S. Department of Transportation, 400 Seventh Street 
SW., Washington DC 20590-0001; or Gary Davis, Office of Flight 
Standards, (202) 267-8166, Federal Aviation Administration, U.S. 
Department of Transportation, 800 Independence Avenue, SW., Washington 
DC 20591.

SUPPLEMENTARY INFORMATION:

I. Background

    On December 30, 1996, RSPA published a notice of proposed 
rulemaking (NPRM) in the Federal Register (61 FR 68955) proposing to 
amend the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180) 
to prohibit the carriage of oxidizers, including compressed oxygen, in 
passenger-carrying aircraft. This proposal also would have the effect 
of limiting packages of oxidizers that are allowed on cargo aircraft to 
locations accessible to crew members (see Sec. 175.85(b)). In the 
December 30, 1996 NPRM, RSPA analyzed the prohibition of oxidizers in 
Class D cargo compartments only, and it proposed a new Sec. 175.85(d) 
to prohibit loading or transporting in a Class D compartment any 
package containing a hazardous material for which an Oxidizer or Oxygen 
label is required. RSPA also stated that it planned to issue a 
supplemental NPRM further analyzing the prohibition of oxidizers aboard 
passenger-carrying aircraft in Class B and C cargo compartments. This 
is the supplemental NPRM to which RSPA referred. If the proposal to 
completely prohibit the transportation of oxidizers on passenger-
carrying aircraft and limit their transportation on cargo aircraft to 
accessible locations is adopted, by adding the word ``Forbidden'' in 
Column 9A of the Hazardous Materials Table in Sec. 172.101 for those 
materials for which an Oxidizer or Oxygen label is required, RSPA would 
not adopt the proposed Sec. 175.85(d), which would prohibit the 
carriage of these materials in Class D compartments only.
    The December 30, 1996 NPRM also proposed several amendments to 
provisions in the HMR concerning chemical oxygen generators. These 
proposed amendments were discussed in Part VII of the preamble to the 
December 30, 1996 NPRM and, in summary, would: (1) Add a shipping 
description for ``Oxygen generator, chemical,'' consistent with the 
recent adoption of this shipping description by the International Civil 
Aviation Organization (ICAO); (2) indicate in Secs. 172.101 (the 
Hazardous Materials Table) and 171.11 that chemical oxygen generators 
may not be transported aboard passenger-carrying aircraft or in 
inaccessible cargo compartments in cargo aircraft; (3) indicate in 
Secs. 171.11, 171.12, and 171.12a that there are no exceptions from HMR 
requirements for classification, approval and description of oxygen 
generators when shipping to, from or within the U.S. under the 
provisions of international or Canadian regulations; (4) specify 
packaging requirements for shipment of chemical oxygen generators; and, 
(5) eliminate an exception in Sec. 175.10(a)(24) pertaining to personal 
chemical oxygen generators carried by passengers in checked baggage.
    RSPA received requests from two airline industry associations to 
withdraw the proposed rule and not issue the supplemental NPRM. These 
requests are denied. RSPA also received several requests to extend the 
comment period on the December 30, 1996 NPRM for either 60 or 90 days. 
These requests were not granted. However, RSPA has accepted all late-
filed comments to the NPRM and, by issuing this supplemental NPRM, RSPA 
is effectively extending until October 20, 1997 the period for comments 
on the proposal in the December 30, 1996 NPRM to prohibit the 
transportation of oxidizers, including compressed oxygen, on board 
passenger-carrying aircraft. RSPA is denying the requests for an 
extension of time to comment on the proposals in the December 30, 1996 
NPRM pertaining to chemical oxygen generators, other than for the 
proposed removal of Sec. 175.10(a)(24). Sufficient time has been 
provided to comment on the generator-related proposals, and RSPA issued 
a final rule on these proposals which was published in the Federal 
Register (62 FR 30767) on June 5, 1997. Also, RSPA issued an extension 
of effective date and corrections to the June 5, 1997 final rule on 
June 27, 1997 (62 FR 34667).
    On May 31, 1996, the National Transportation Safety Board (NTSB) 
issued two recommendations to RSPA, the following of which is pertinent 
to this discussion:

    In cooperation with the Federal Aviation Administration, 
prohibit the transportation of oxidizers and oxidizing materials 
(e.g., nitric acid) in cargo compartments that do not have fire or 
smoke detection systems. (Class I, Urgent Action) (A-96-30)

    This NPRM was developed by RSPA in cooperation with the FAA. The 
actions proposed herein go beyond the NTSB recommendation and are based 
on a preliminary assessment by RSPA and the FAA of the hazards posed by 
oxidizers aboard aircraft. In its recommendation, NTSB cited three 
previous incidents in which oxidizers caused fires aboard aircraft. In 
each of these incidents, there were apparent or known serious 
violations of the HMR.

[[Page 44375]]

Although RSPA and FAA are not aware of any fire aboard an aircraft 
having been caused directly by transport of oxidizers in conformance 
with the HMR, RSPA and FAA agree that oxidizers may pose an 
unacceptable risk when transported aboard passenger-carrying aircraft 
and when transported aboard cargo aircraft in locations inaccessible to 
crew members.
    Both the NTSB's recommendation and this proposed rule address risks 
that do not depend on or involve any violation of requirements 
currently in the HMR regarding the transportation of oxidizers. For 
that reason, RSPA and FAA disagree with opinions that better 
enforcement of the HMR would be sufficient to eliminate the risks 
present in transporting oxidizers on board passenger-carrying aircraft.

II. Oxidizers Under the HMR

    Under the HMR, an oxidizer (Division 5.1) is a material that may, 
generally by yielding oxygen, cause or enhance the combustion of other 
materials (see 49 CFR 173.127). Hydrogen peroxide, swimming pool 
chlorine, bleach and oxygen are examples of commonly used oxidizers. 
Liquid and solid materials in Division 5.1 are subdivided into Packing 
Groups I, II, or III, a relative ranking corresponding to high, 
moderate or low risks posed by the material. Packing groups are 
assigned to specifically named materials in the Sec. 172.101 Hazardous 
Materials Table (Table). For generic entries, such as ``Oxidizing 
solid, n.o.s.'' (``n.o.s.'' means ``not otherwise specified''), packing 
groups are assigned on the basis of test results. Certain gases (Class 
2), most notably oxygen, are also oxidizers under the HMR and, even 
though they are not classed as such, they are required to be identified 
with the OXIDIZER or OXYGEN label.

III. Oxidizers Aboard Aircraft

    Liquid oxidizers in Packing Group I are very reactive and have the 
ability to initiate and substantially intensify fires. These materials 
currently are forbidden for transportation by passenger-carrying 
aircraft. Some are also forbidden for transportation by cargo aircraft, 
and others are permitted only in restricted quantities aboard cargo-
only aircraft when loaded in a manner which renders them accessible to 
a crew member during flight. Liquid or solid oxidizers that will 
initiate a fire are not permitted on passenger-carrying aircraft. 
However, gaseous oxygen is permitted on passenger-carrying aircraft; 
combustible materials can be readily ignited, by impact, high 
temperature, or flame, if exposed to gaseous oxygen.
    In the absence of a fire caused by another source, oxidizers 
currently authorized for air transportation and offered in conformance 
with the HMR present minimal risks to aircraft, crew and passengers. 
Most oxidizers will not initiate fires when spilled or released, but 
they will intensify fires originating from other sources. The potential 
hazard posed by these oxidizers in an aircraft cargo compartment is 
that, if a fire were to occur elsewhere in the compartment, the fire 
may involve the oxidizer, and most oxidizers would then provide an 
oxygen-enriched environment which could intensify the fire and override 
the safety features of the compartment.
    When transported by aircraft, an oxidizer is subject to per package 
quantity limits specified in the Hazardous Materials Table, and to 
aircraft quantity limits specified in Sec. 175.75. For oxidizers 
forbidden aboard a passenger-carrying aircraft but permitted aboard a 
cargo aircraft, packages must be labeled (see Sec. 172.101(j)(4)) with 
the Cargo Aircraft Only label specified in Sec. 172.448 and, under the 
provisions of Sec. 175.85(b), must be loaded in a manner so that they 
are accessible to a crew member during flight.

IV. Prohibition of Oxidizers on Passenger-carrying Aircraft and in 
Inaccessible Locations on Cargo Aircraft

    In the December 30, 1996 NPRM, RSPA proposed to prohibit the 
loading or transportation aboard a passenger-carrying aircraft of any 
package for which an Oxidizer or Oxygen label (see Secs. 172.405 and 
172.426) is required under subpart E of part 172. Consistent with that 
proposal, in this supplemental NPRM, RSPA proposes to revise Column 9A 
of the Hazardous Materials Table, pertaining to quantity limitations on 
passenger aircraft, to read ``Forbidden'' for every shipping 
description that requires an Oxidizer or an Oxygen label. For oxidizers 
currently authorized for transportation aboard both passenger-carrying 
aircraft and cargo aircraft, the effect of this action would be that 
packages now would be labeled (see Sec. 172.101(j)(4)) with the Cargo 
Aircraft Only label specified in Sec. 172.448 and would be subject to 
the provisions of Sec. 175.85(b). Paragraph (b) of Sec. 175.85 
restricts hazardous materials that are forbidden aboard passenger-
carrying aircraft, but authorized aboard cargo aircraft, to locations 
where ``a crew member or other authorized person can see, handle, and 
where size and weight permit, separate such packages from other cargo 
during flight.'' This means that oxidizers also will be forbidden to be 
transported on a cargo aircraft in an inaccessible cargo compartment 
(e.g., a Class C or D cargo compartment) or in an accessible cargo 
compartment in a manner which renders the oxidizer inaccessible.
    There are certain hazardous materials which may be listed in the 
Hazardous Materials Table as ``Forbidden'' on passenger-carrying 
aircraft but which may be permitted on passenger-carrying aircraft 
under the provisions of exceptions elsewhere in the HMR, such as for 
compressed oxygen as proposed in this notice. RSPA is proposing a minor 
change to Sec. 175.85(b) to clarify that any package bearing a Cargo 
Aircraft Only label must be stowed accessibly on cargo aircraft, even 
though there may be specific exceptions elsewhere in the regulations 
which allow the material on passenger-carrying aircraft under certain 
conditions.
    The December 30, 1996 NPRM discussed the classification of cargo 
compartments into five categories, Classes A, B, C, D, and E (see 14 
CFR 25.857), as defined for transport category aircraft in FAA's 
Federal Aviation Regulations (FAR). Although these categories are also 
referenced in the following paragraphs and elsewhere in this preamble, 
it should be noted that the proposals in this supplemental NPRM address 
all aircraft without regard to whether they are transport category 
aircraft or not. Thus, this proposal would prohibit oxidizers in cargo 
compartments of all transport category and nontransport category 
aircraft used in passenger-carrying service.

Class B Compartments on Passenger-Carrying Aircraft

    A Class B compartment is one: (1) To which any part of the 
compartment is accessible in flight to a crew member with a hand held 
fire extinguisher; (2) from which no hazardous quantities of smoke, 
flames, or extinguishing agent will enter any compartment occupied by 
the crew or passengers when the compartment is being accessed; and (3) 
in which an approved smoke detector or fire detector system is 
installed. Under the provisions of 49 CFR 175.85 (a) and (b), hazardous 
materials transported in a Class B compartment must be inaccessible to 
passengers but accessible to crew members.
    In the event of a fire in a Class B cargo compartment, protective 
breathing equipment should protect crew members from smoke and fumes. 
However, supplemental oxygen breathing systems for passengers are 
designed to provide a combination of supplemental oxygen and ambient 
cabin

[[Page 44376]]

air for use in emergency decompression situations. These breathing 
systems are not designed to protect passengers from smoke and fumes, 
and passengers would continue to inhale some amount of ambient air in 
the cabin. According to FAA, a fire fed by a secondary source of oxygen 
would create additional smoke and fume risks to passengers that would 
not otherwise be present in fires that are not fed by a secondary 
source of oxygen. Dangerous or even fatal levels of smoke and fumes are 
more likely to develop and migrate to the passenger cabin when a fire 
is fed by a secondary source of oxygen.
    According to the FAA, even if a halon fire-suppressant system is 
present, although effective against most fires, it may not be effective 
against an oxidizer-fed fire. If a water fire extinguisher is used, it 
may not have a sufficient quantity of water to extinguish a fire that 
continues to reignite because it is being fed by an oxygen source. 
Although all areas of a Class B compartment must be accessible to the 
contents of a hand-held fire extinguisher, oxidizers stowed in a 
compartment where other materials are burning may be difficult or 
impossible to remove or otherwise keep away from the fire.

Class C Compartments

    A Class C compartment is not accessible during flight but has: (1) 
An approved smoke detector or fire detector system; (2) an approved 
built-in fire-extinguishing system; (3) means to control ventilation 
and drafts so that the extinguishing agent can control a fire that may 
start within the compartment; and (4) means to exclude hazardous 
quantities of smoke, flames or extinguishing agent from any compartment 
occupied by crew or passengers.
    While Class C cargo compartments have safety features that can 
control most types of fires, RSPA and FAA believe that an oxygen-fed 
fire can overcome these safety features and pose an unacceptable risk 
in the aviation environment. Moreover, an oxygen-fed fire in a Class C 
compartment may present a greater risk than a fire in a Class B 
compartment. Unlike a Class B compartment that a crew member can 
physically enter, a Class C compartment is not physically accessible to 
crew members. Thus, for a Class C compartment, there is no possibility 
for a crew member to remove an oxidizer from the area of the fire or to 
attack the fire with a hand-held extinguisher.
    A fire that is fed by a secondary source of oxygen increases the 
risk that flames, toxic smoke or fumes may cause injury or death. It 
also increases the risk that control of the aircraft will be lost. This 
may be caused by damage to the aircraft's flight control cables, 
hydraulic systems, electrical systems or structure, or entry of fire 
and smoke into the aircraft's cabin. For the reasons set forth above, 
RSPA is proposing to prohibit the transportation of oxidizers aboard 
passenger-carrying aircraft and in inaccessible locations aboard cargo 
aircraft.

V. Exceptions for Carriage of Oxygen on Passenger-carrying Aircraft

    RSPA is proposing to add a special provision in Sec. 172.102 and to 
the Hazardous Materials Table entry for ``Oxygen, compressed,'' to 
clarify that certain exceptions are provided in Sec. 175.10 for 
carriage of oxygen on passenger-carrying aircraft. These exceptions, 
some of which are in the HMR at present and some of which are proposed 
in this notice, are discussed in the following paragraphs.

Oxygen for Use of Passengers During Flight

    The proposed prohibition against transportation of oxidizers as 
cargo would not affect the existing exception in 49 CFR 175.10(a)(7) 
for operator-supplied oxygen for a passenger's use during flight or the 
exception in 49 CFR 175.10(a)(14) for a transport incubator unit 
necessary to protect life, or an organ preservation unit necessary to 
protect human organs.
    As proposed in the December 30, 1996 NPRM, RSPA is proposing an 
editorial change to Sec. 175.10(a)(7) to clarify that this exception 
applies only to oxygen furnished by an aircraft operator for medical 
use of an onboard passenger and does not allow the aircraft operator to 
transport medical oxygen cylinders as cargo in order to move them to 
the locations where they will be needed, at a later time, for use by 
passengers. This proposal is included in the regulatory text of this 
supplemental NPRM for convenience of the reader.

Personal Use Chemical Oxygen Generators in Checked Baggage

    As proposed in the December 30, 1996 NPRM, RSPA is proposing in 
this supplemental NPRM to remove the exception provided in 
Sec. 175.10(a)(24) for small personal chemical oxygen generators in 
checked baggage. See the December 30, 1996 NPRM for additional 
discussion of this proposal.

Aircraft Operators' and Passengers' Own Oxygen Cylinders

    In this supplemental NPRM, RSPA is proposing provisions by which an 
aircraft operator may transport limited numbers of the operator's own 
cylinders (e.g., replacements for cylinders required aboard an aircraft 
or cylinders being returned for maintenance) containing compressed 
oxygen aboard passenger-carrying aircraft and by which an air carrier 
may transport a cylinder belonging to a passenger needing oxygen at 
destination for personal medical use.
    As indicated in the December 30, 1996 NPRM, FAA supports a complete 
removal of oxidizers from passenger-carrying aircraft but also believes 
that, if it is necessary to allow a passenger to transport his or her 
own oxygen cylinder for use at destination, it is far safer to stow the 
cylinder in the passenger cabin, under the control of and accessible to 
the airline crew, than in an inaccessible cargo compartment. FAA does 
not believe that oxygen should be carried in inaccessible cargo 
compartments. FAA believes that, if an oxygen cylinder is involved in a 
fire, the release of oxygen will intensify the fire and a fire that 
might otherwise be survivable has an increased risk of becoming fatal. 
Thus, FAA believes that it would be safer to carry personal medical 
oxygen cylinders in the cabin because the crew could quickly remove the 
cylinders from any fire area in the cabin. This is in contrast to the 
complete inability of the crew to remove compressed oxygen from an 
inaccessible cargo compartment.
    RSPA believes that oxygen can be safely transported aboard 
passenger-carrying aircraft and that there is a continuing need, for 
reasons of safety, service to passengers and potential cost impacts of 
a total prohibition, to permit an airline to transport its own oxygen 
cylinders and to transport a cylinder belonging to a passenger needing 
oxygen at destination for personal medical use. RSPA's proposal 
provides airlines a means of using their own passenger-carrying 
aircraft to position oxygen cylinders needed by passengers on 
subsequent flights or to place oxygen cylinders used on aircraft, such 
as those used for the flight crew's personal breathing equipment or 
emergency-use medical oxygen. Although oxygen cylinders required on 
aircraft by FAA regulations are not subject to the HMR, replacements 
carried aboard aircraft are. This proposed exception will provide an 
alternative to cargo aircraft or surface transportation for 
prepositioning essential supplies of oxygen.

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    At present, a passenger who needs supplemental oxygen may ship it 
in conformance with the HMR when it is offered and accepted as air 
cargo by an airline that is capable and willing to transport hazardous 
materials and has procedures for handling hazardous materials which 
have been approved by the FAA under existing rules (e.g., 14 CFR 
121.25, 121.135, 135.21, and 135.23). It may be carried as cargo (i.e., 
as freight rather than as checked baggage) on the same aircraft 
carrying the passenger. The advantage is that the passenger would have 
that oxygen available for use at destination without having to arrange 
with an oxygen supplier, if one services the destination airport, to 
charge the passenger's cylinder or provide a supplier-owned charged 
cylinder upon arrival.
    Under this proposed rule, carriage of oxygen in cargo compartments 
on passenger-carrying aircraft would no longer be permitted. However, 
the exception proposed in Sec. 175.10(b) would permit an airline to 
carry a passenger's oxygen cylinder on the same aircraft as the 
passenger in the same manner as the airline carries its own cylinders. 
The oxygen cylinder would not be available to the passenger during 
flight; only oxygen furnished by the aircraft operator under the 
provisions of 49 CFR 175.10(a)(7) would be available for use during 
flight.
    Based on FAA's assessment of the potential hazards of compressed 
oxygen in a cargo compartment, RSPA is proposing much more restrictive 
provisions for its carriage on passenger-carrying aircraft than 
currently apply, particularly that the oxygen be carried only in the 
cabin of the aircraft. The aircraft operator would be limited to no 
more than six of its own cylinders and no more than one cylinder 
belonging to each passenger needing the oxygen at destination, and 
would have to overpack each cylinder in a fire-resistant metal or 
plastic case. A passenger's cylinder would be limited in rated capacity 
to 850 liters (30 cubic feet) or less of oxygen.
    In addition to being labeled for the oxygen hazard (i.e., with 
either Oxygen or Non-Flammable Gas and Oxidizer labels, as specified in 
subpart D of Part 172), each cylinder and overpack would be required to 
be labeled with a Cargo Aircraft Only label to ensure that the overpack 
does not get placed in any cargo compartment on a passenger-carrying 
aircraft or in an inaccessible compartment or location when transported 
on cargo aircraft. The overpack would be marked with the proper 
shipping name and identification number (i.e., Oxygen, Compressed, 
UN1072), and with the statement ``Passenger cabin acceptable per 49 CFR 
175.10'' to explain the apparent discrepancy concerning appearance of a 
Cargo Aircraft Only label on an overpack in the cabin of a passenger-
carrying aircraft.
    Prior to placing a cylinder in an overpack, the aircraft operator 
would be required to check that the cylinder's valves are closed and 
the cylinder is free of flammable contaminants. The aircraft operator 
would then stow the overpack in the passenger cabin in accordance with 
procedures approved by the FAA and notify the pilot-in-command as to 
the presence and location of the cylinder. Air carriers currently are 
required to have FAA-approved procedures in operations manuals, plans 
or specifications if they carry hazardous materials.
    RSPA currently permits the carriage of oxygen cylinders in 
passenger compartments by several aircraft operators under the 
provisions of an exemption, DOT-E 10114. The purpose of the exemption 
is to facilitate the predeployment, and return for maintenance, of 
cylinders owned and maintained by an aircraft operator for use by 
passengers needing oxygen during flight. The provisions of the 
exemption serve as a basis for this rulemaking proposal and, although 
not authorized under the exemption, have been expanded to cover 
carriage by an aircraft operator of a passenger's own cylinder. RSPA 
anticipates that the exemption would no longer be necessary if this 
proposal becomes a final rule.

VI. Effects on Individuals With Disabilities

    RSPA and FAA believe that exceptions for shipment and use of oxygen 
proposed in 49 CFR 175.10(b) eliminate any negative effects this 
rulemaking may have on passengers who need supplemental breathing 
oxygen when they disembark from aircraft at their destination and on 
the ability of airlines to preposition or stage oxygen at various 
locations for use by passengers. RSPA is interested in receiving 
comments from oxygen users, air carriers, and suppliers of oxygen about 
these effects and whether the proposed provisions for carriage of 
oxygen in passenger cabins are a safe and feasible alternative to a 
total prohibition.
    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 not 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 to passengers. Also, compressed oxygen, while 
regulated as a hazardous material, is different in form from other 
oxidizers which are usually liquids and solids. RSPA requests comments 
as to whether there is any evidence (e.g., accident or incident 
information, studies, etc.) to suggest that gaseous oxygen in 
cylinders, as distinct from chemical oxidizers, poses or has created 
significant safety problems while being transported in cargo 
compartments.
    FAA, RSPA, and the Office of the Secretary are initiating a project 
separate from this rulemaking action to explore whether safe 
alternatives exist for accommodating passenger needs in regard to use 
of oxygen. This project could 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.

VII. Spent Oxygen Generators

    RSPA is proposing to prohibit the transportation by aircraft of 
spent chemical oxygen generators (i.e., generators in which the means 
of initiation and the chemical core have been expended) and to regulate 
them as Class 9 materials when transported by other than aircraft. This 
proposal was not in the December 30, 1996 NPRM.
    Spent chemical oxygen generators currently may be regulated as 
hazardous wastes because of the residual materials contained therein. 
They may also pose a hazard in transportation by containing unburned 
oxidizing materials.
    Regardless of the degree of hazard posed by the chemical contents, 
it can be difficult to confirm that a generator truly is spent. Human 
error in assessing whether such devices are, in fact, empty can result 
in a catastrophe. RSPA and FAA believe that lessening the possibility 
that this type of human error may occur outweighs any interest or need 
for transporting spent chemical oxygen generators by aircraft.
    Based on the foregoing, RSPA is proposing to add to the Hazardous 
Materials Table (HMT) an entry for spent chemical oxygen generators. A

[[Page 44378]]

new shipping description, ``Oxygen generator, chemical, spent, 9, 
NA3356, III'' would be added. The entry would be preceded by a plus 
(``+'') in Column 1 to fix the proper shipping name, hazard class and 
packing group for the entry without regard to whether the material 
meets the definition of Class 9 or Packing Group III. Special provision 
61 would be added in Column 7 to specify the conditions under which an 
oxygen generator is considered ``spent.'' For transportation aboard 
passenger-carrying and cargo aircraft, Columns 9a and 9b would read 
``Forbidden.'' RSPA also proposes to amend Secs. 171.11, 171.12 and 
171.12a, consistent with its proposal in the December 30, 1996 NPRM, to 
indicate that there are no exceptions from HMR requirements for 
classification, description, and packaging of spent chemical oxygen 
generators when shipping to, from or within the U.S. under the 
provisions of international or Canadian regulations.

VIII. Cost/Benefit Analysis

Analysis of Costs

    The preliminary regulatory evaluation ``Prohibition of Oxidizers 
and Oxidizing Materials as Cargo in Aircraft'' (June 1997) developed in 
support of this supplemental NPRM revises the earlier estimate of 10-
year costs associated with the December 30, 1996 proposal to prohibit 
oxidizers in Class D cargo compartments from $25 million ($17 million, 
discounted) to $18 million ($12 million, discounted). This supplemental 
NPRM would impose additional costs on air carriers by prohibiting 
oxidizers in Class B and C cargo compartments on passenger aircraft and 
all inaccessible compartments in cargo-only aircraft. The additional 
cost of compliance (in the form of lost revenue) to air carriers 
imposed by this proposal is estimated to be $17 million ($12 million, 
discounted), in 1996 dollars, over the next 10 years.
    RSPA and FAA are aware that the estimated cost associated with the 
proposed prohibition on oxidizers does not include any reduction in 
variable operating costs, such as fuel savings, that may result due to 
less weight being carried aboard the aircraft. In addition, this cost 
estimate may not represent a net loss to the aviation industry, as RSPA 
and FAA expect much of the affected traffic would shift to cargo-only 
operators. Overall cost to the aviation industry may, therefore, be 
less than the 10-year costs estimated for this proposed rule.
    RSPA and FAA have not identified any cost impacts to cargo aircraft 
carriers, but recognize there could, nonetheless, be potential 
logistical impacts. Occasionally, hazardous materials are tendered for 
shipment that are not compatible and must be separated during 
transport. Currently, these materials may be transported in separate 
compartments. Therefore, the proposed rule may have an impact upon 
cargo airlines because of the airline's inability to transport 
incompatible hazardous materials on the same flight. As a result, one 
of the hazardous materials tendered to the airline for transport may 
experience a delay. RSPA solicits information from cargo-only aircraft 
operators that may incur this, or other, costs due to implementation of 
the proposed rule.
    RSPA and FAA expect that the total compliance cost to the aviation 
industry attributed to this proposed rule would be borne by operators 
of passenger-carrying aircraft.
    This supplemental NPRM expands, also, the prohibition of carriage 
of chemical oxygen generators aboard passenger-carrying aircraft by 
proposing to prohibit the shipment of spent chemical oxygen generators 
on aircraft. Because a spent chemical oxygen generator has no residual 
or economic value, and there is no urgent need to ship it by aircraft, 
RSPA and FAA determined there is essentially no adverse cost impact 
associated with the proposed prohibition.
    RSPA has received comments on the potential costs of the NPRM. 
These comments and cost-related comments to this supplemental NPRM will 
be taken into account in developing a final regulatory evaluation prior 
to issuance of a final rule.

Analysis of Benefits

    Notwithstanding current regulatory restrictions, hazardous 
materials, including oxidizers, are occasionally improperly carried in 
airplane cargo compartments through inadvertent or deliberate package 
mislabeling. Over the past 10 years, there are only two documented 
incidents where oxidizers (of types other than chemical oxygen 
generators) were known to be present in the cargo compartment of a U.S. 
air carrier when a fire occurred. Those incidents resulted only in 
minor injuries and damage, though damage from one of the fires extended 
outside the cargo compartment. RSPA and FAA believe, however, that the 
risk of fire as evidenced by the number of actual fires that have 
occurred justifies this proposed prohibition on the carriage of 
oxidizers in inaccessible cargo compartments.
    One analytical tool commonly used in the statistical analysis of 
rare events is the Poisson probability distribution. This tool provides 
a means to statistically estimate the probability of the occurrence of 
rare and random events based on an observed rate of occurrence. In the 
case of cargo compartment fires in the presence of oxidizers, the 
observed mean is two over 10 years. The Poisson probability 
distribution with a mean of two suggests there is a small chance (14 
percent) that there would be no oxidizer fires in the next decade based 
on the past accident history. However, there is an 86 percent 
probability of one or more such fires. In addition, there is a 14 
percent probability that there would be four or more fires with 
oxidizers present.
    Any one of these probable events could be more serious than the two 
reported incidents. According to the FAA, fire aboard an aircraft is 
one of the greatest threats to safety that can happen in air 
transportation. For example, an Air Canada flight from Dallas in 1983 
made an emergency landing at the Greater Cincinnati International 
Airport because of a fire of undetermined origin. As soon as the 
airplane stopped, it was evacuated. However, 23 passengers were unable 
to exit the aircraft before the interior was engulfed in a flash fire. 
In 1983 a British Airtours flight was aborted during takeoff and 55 of 
the 137 persons onboard were unable to evacuate before a fire engulfed 
and destroyed the aircraft.
    With respect to spent chemical oxygen generators, the Poisson 
probability distribution with a mean of four suggests, in the absence 
of any regulatory action, that there is only a 2 percent probability of 
no chemical oxygen generator fire in the next decade, based on actual 
incident and accident history. But, there is a 98 percent probability 
there will be one or more such fires in the same time period. In the 
absence of a regulatory prohibition on their carriage, there is a 57 
percent probability of four or more incidents and accidents in the next 
10 years, as there were in the last 10 years, involving chemical oxygen 
generators.
    To determine the potential benefits that would result from this 
proposed rule, RSPA and FAA estimated the average costs associated with 
potential future fire accidents involving ``spent'' chemical oxygen 
generators. In the May 11, 1996 incident, there were 110 casualties and 
a McDonnell Douglas DC-9-32 was destroyed. The monetary value of this 
loss was ascertained in several steps. First, a critical economic value 
of $2.7 million was applied to each human casualty. This computation 
resulted in an estimate of $297 million ($2.7 million x 110). Next the 
value of

[[Page 44379]]

the destroyed aircraft was estimated to be $6 million. If this 
rulemaking prevents one such catastrophic incident over the next 10 
years, the expected value of potential safety benefits would be $303 
million ($213 million, discounted).
    This supplemental NPRM reduces the chance that a cargo compartment 
fire will be enhanced by an oxidizer, thereby increasing the likelihood 
that a cargo compartment fire would be successfully contained or 
extinguished. One measure of calculating whether the proposed 
prohibition on oxidizers is cost-beneficial is to determine if it would 
prevent incidents that otherwise would claim at least thirteen lives 
over the next 10 years. RSPA and FAA are confident this proposed 
prohibition has the potential to achieve that level of benefits.

Relation to FAA Rulemaking on Cargo Compartments

    The FAA has proposed to upgrade fire safety standard for cargo or 
baggage compartments by eliminating Class D compartments and requiring 
their conversion to the equivalent of Class C or Class E compartments. 
The NPRM is entitled ``Revised Standards for Cargo or Baggage 
Compartments in Transport Category Airplanes,'' 62 FR 32412 (June 13, 
1997). While the benefits of these two proposed rules would overlap 
somewhat, each of them will also provide benefits that the other would 
not. The FAA's proposed rule addresses the risks of any fire in an 
inaccessible cargo compartment that lacks fire or smoke detection and 
suppression (including a situation when no oxidizer is present). This 
proposed rule addresses the risks of transporting an oxidizer on board 
a passenger-carrying aircraft (even when carried in a compartment with 
fire or smoke detection and suppression equipment). FAA has determined 
that both initiatives would yield benefits that justify their costs, 62 
FR 32420, but interested parties are invited to submit comments on the 
potential for overlap in the benefits of these two proposed rules.

Comparison of Costs and Benefits

    The proposed restrictions contained in the NPRM and this 
supplemental NPRM would impose an estimated 10-year cost of $35 million 
($24 million, discounted) by prohibiting the shipment of oxidizers on 
passenger-carrying aircraft, and no identified costs by prohibiting the 
shipment of spent oxygen generators on passenger-carrying aircraft. 
While RSPA and FAA have been unable to estimate quantitative potential 
safety benefits for prohibiting the shipment of oxidizers, the high 
level of risk created by the presence of those hazardous materials 
aboard aircraft warrants adoption of the prohibitions. Preventing one 
catastrophic incident like the May 11, 1996 ValuJet accident, would 
result in calculated safety benefits of $303 million ($213 million, 
discounted over ten years).

IX. Request for Additional Comments

    RSPA requests that interested parties provide additional 
information concerning the costs and benefits of this proposed action. 
RSPA also requests information concerning the hazards posed by 
oxidizers in aircraft cargo compartments that have fire detection or 
suppression systems. RSPA requests that shippers and carriers, 
including foreign carriers, provide detailed cost information to RSPA 
as to the type and amounts of any costs that may result from the 
proposed prohibition of oxidizers on passenger-carrying aircraft.
    In evaluating the costs and benefits of the proposed rule, RSPA and 
FAA have assumed that cargo aircraft operators would not incur any 
costs because of their ability to transport oxidizers in accessible 
cargo compartments of an aircraft. In addition, RSPA and FAA have 
assumed that there would be little or no impact on shippers of 
oxidizers because of the availability of other means of transportation 
(e.g., cargo aircraft or highway transportation).
    RSPA and FAA have not assessed the costs associated with 
prohibiting the shipment of oxygen cylinders on passenger-carrying 
aircraft. Although the proposed exceptions in Sec. 175.10(b) serve to 
mitigate any adverse impacts, there may be some costs to air carriers 
if they routinely use passenger-carrying aircraft to transport, as 
cargo, oxygen cylinders which are normally installed or required on 
aircraft and must be periodically retested or refilled, or which are 
prepositioned for use by passengers on subsequent flights. Therefore, 
RSPA requests information concerning the costs and benefits of 
prohibiting cylinders containing oxygen, aboard passenger-carrying 
aircraft. Please provide detailed information as to the manner by which 
costs may be incurred. In particular, RSPA requests information on (1) 
the number of cylinders of oxygen which are transported each day on 
passenger-carrying aircraft; (2) the typical size of these cylinders; 
(3) other means of transportation that are available; and (4) the cost 
differences to the airlines for using other means of transportation.
    RSPA requests comments concerning any hardships that may be caused 
in remote areas, such as Alaska, where frequent cargo-only air service 
may not be available, and suggestions for limiting this hardship.
    By limiting the prohibition on oxidizers to packages required to be 
labeled Oxidizer and Oxygen, the prohibition would not apply to 
oxidizers renamed ``consumer commodity'' and reclassed as ORM-D under 
the provisions of Sec. 173.152, or as consumer commodities, Class 9, as 
permitted under Sec. 171.11. RSPA requests comments regarding whether 
it would be appropriate to extend this prohibition to consumer 
commodities which are oxidizers or whether more restrictive packaging, 
per package quantity limits, or aircraft quantity limits should be 
imposed on these materials.

X. Study To Assess the Risks Associated With Transportation of 
Hazardous Materials in Aircraft Cargo Compartments

    RSPA, in coordination with FAA, has initiated a study to assess the 
risks associated with the transportation of hazardous materials in 
aircraft cargo compartments. As beginning steps, RSPA assembled a panel 
of experts and held meetings in Cambridge, Massachusetts on October 22 
and 23, 1996, and in Washington, D.C. on June 10 through 12, 1997, for 
purposes of identifying accident scenarios, probabilities of 
occurrence, and expected consequences. In attendance at the meetings 
were representatives from the NTSB, FAA, Air Transport Association of 
America, Chemical Manufacturers Association, Air Line Pilots 
Association, International Air Line Passenger Association and several 
aircraft manufacturers. Based on the outcome of this study, RSPA may 
initiate rulemaking to prohibit or further limit the transportation of 
other types of hazardous materials on aircraft.

XI. Regulatory Analyses and Notices

Executive Order 12866 and DOT Regulatory Policies and Procedures

    This proposed rule is considered a significant regulatory action 
under section 3(f) of Executive Order 12866 and was reviewed by the 
Office of Management and Budget. The rule is considered significant 
under the regulatory policies and procedures of the Department of 
Transportation (44 FR 11034). A preliminary regulatory evaluation is 
available for review in the public docket. A summary of the costs and 
benefits of this supplemental NPRM is set forth in Section VIII of this 
preamble.

[[Page 44380]]

Executive Order 12612

    This proposed rule has been analyzed in accordance with the 
principles and criteria contained in Executive Order 12612 
(``Federalism''). The Federal hazardous materials transportation law 
(49 U.S.C. 5101-5127) contains an express preemption provision that 
preempts State, local, and Indian tribe requirements on certain covered 
subjects. Covered subjects are:
    (A) The designation, description, and classification of hazardous 
material;
    (B) The packing, repacking, handling, labeling, marking, and 
placarding of hazardous material;
    (C) The preparation, execution, and use of shipping documents 
pertaining to hazardous material and requirements respecting the 
number, content, and placement of such documents;
    (D) The written notification, recording, and reporting of the 
unintentional release in transportation of hazardous material; or
    (E) The design, manufacturing, fabrication, marking, maintenance, 
reconditioning, repairing, or testing of a package or container which 
is represented, marked, certified, or sold as qualified for use in the 
transportation of hazardous material.

Because RSPA lacks discretion in this area, preparation of a federalism 
assessment is not warranted.
    Title 49 U.S.C. 5125(b)(2) provides that DOT must determine and 
publish in the Federal Register the effective date of Federal 
preemption. That 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. This proposed rule would require 
oxidizers to be transported in certain types of cargo compartments 
aboard aircraft. RSPA solicits comments on whether the proposed rule 
would have any effect on State, local or Indian tribe requirements and, 
if so, the most appropriate effective date of Federal preemption.

Regulatory Flexibility Act

    The Regulatory Flexibility Act of 1980 (RFA) was enacted by 
Congress to ensure that small entities (small business and small not-
for-profit organizations which are independently owned and operated, 
and small government jurisdictions) are not unnecessarily and 
disproportionately burdened by Federal regulations. The RFA requires 
regulatory agencies to review rules which may have ``a significant 
economic impact on a substantial number of small entities.'' Since this 
proposed rule would primarily impact those entities operating under 14 
CFR part 121, RSPA and FAA adopted the Federal Aviation Administration 
(FAA) Order 2100.14A (Regulatory Flexibility Criteria and Guidance) as 
the standard by which the potential impact on small entities would be 
determined. The potential impact on small entities is the cost (revenue 
losses) incurred by carriers that currently transport oxidizers and 
spent chemical oxygen generators. There is very little data to 
determine the proposed rule's economic impact on entities other than 
those operating under 14 CFR part 121 (e.g., part 135 operators). 
Therefore, RSPA requests comments on the economic impact, if any, of 
this proposed rule on other entities.
    According to FAA Order 2100.14A, a substantial number of small 
entities is defined as a number which is not less than eleven and which 
is more than one-third of the small entities subject to a proposed or 
existing rule. A significant economic impact refers to the annualized 
threshold assigned to each entity group potentially impacted by 
rulemaking actions. For this proposed rule, the small entities are 
eight 14 CFR part operators (scheduled and non-scheduled) that carry 
hazardous materials. The annualized significant economic impact 
threshold for non-scheduled aircraft operators is estimated to be 
$4,900. Similarly, the annualized significant economic impact threshold 
for scheduled aircraft operators is estimated to be $70,100 (operators 
with less than 60 passenger seats) and $125,500 (operators with more 
than 60 passenger seats).
    A small entity is defined in the FAA Order 2100.14A as an operator 
of aircraft for hire with nine or fewer aircraft owned but not 
necessarily operated. RSPA and FAA identified a total of eight 
operators that meet this definition. Those operators comprise two 
groups: (1) Non-scheduled small part 121 operators and (2) scheduled 
small part 121 operators.
    To determine the impact of the proposed rule on these small 
entities, RSPA and FAA estimated the annualized cost impact on each of 
those small entities within the two groups. The annualized cost impact 
per small entity is based on the annual number of ton miles for 
oxidizer shipments times the respective revenue-per-ton-mile estimate.
Small Entities, Non-scheduled
    RSPA and FAA determined there are six non-scheduled part 121 
aircraft operators that meet the definition of a small entity. Of the 
six small entities within this group, only two would have annualized 
costs that exceed the significant economic impact threshold of $4,900. 
While one-third of the above aircraft operators would incur significant 
economic costs, a substantial number of them would not be impacted 
because their number is less than eleven.
Small Entities, Scheduled
    RSPA and FAA also determined that there are two part 121 scheduled 
aircraft operators that meet the definition of a small entity. The ten-
year estimated cost of compliance for the scheduled entity with less 
than 60 passenger seats would be $60,000 ($42,200, discounted). 
Similarly, for the entity with more than 60 passenger seats, the ten-
year cost of compliance would be $9,800 ($6,900, discounted). Over a 
ten-year period, the annualized potential cost of compliance for the 
entity with less than 60 passenger seats and the entity with more than 
60 passenger seats would be $6,000 and $1,000, respectively. These 
annualized cost of compliance estimates are far less than their 
respective significant economic thresholds of $70,100 and $125,500.
    Based upon the above, I certify that this proposed rule would not 
have a significant economic impact on a substantial number of small 
entities. While the proposed rule would have a significant economic 
impact on two of the eight small entities examined in this analysis, it 
would not impact a substantial number of those small entities.

Paperwork Reduction Act

    This supplemental notice of proposed rulemaking does not impose any 
new information collection requirements.

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.

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, Marking, Packaging and

[[Page 44381]]

containers, Reporting and recordkeeping requirements.

49 CFR Part 175

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

    In consideration of the foregoing, 49 CFR parts 171, 172, and 175 
are proposed to be amended as follows:

PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS

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

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

    2. In Sec. 171.11, paragraph (d)(15) is revised and paragraph 
(d)(16) is added to read as follows:


Sec. 171.11  Use of ICAO Technical Instructions.

* * * * *
    (d) * * *
    (15) An oxygen generator (chemical) must be classed, approved, and 
described in accordance with the requirements of this subchapter and an 
oxygen generator, chemical, spent, must be classed, described and 
packaged in accordance with the requirements of this subchapter.
    (16) A package containing a hazardous material for which an 
Oxidizer or Oxygen label is required under part 172, subpart E, of this 
subchapter, may not be offered for transportation or transported in a 
passenger-carrying aircraft except as specified in this subchapter.
    3. In Sec. 171.12, paragraph (b)(18) is revised to read as follows:


Sec. 171.12  Import and export shipments.

* * * * *
    (b) * * *
    (18) An oxygen generator (chemical) must be classed, approved, and 
described in accordance with the requirements of this subchapter and an 
oxygen generator, chemical, spent, must be classed, described and 
packaged in accordance with the requirements of this subchapter.
* * * * *
    4. In Sec. 171.12a, paragraph (b)(17) is revised to read as 
follows:


Sec. 171.12a  Canadian shipments and packagings.

* * * * *
    (b) * * *
    (17) An oxygen generator (chemical) must be classed, approved, and 
described in accordance with the requirements of this subchapter and an 
oxygen generator, chemical, spent, must be classed, described and 
packaged in accordance with the requirements of this subchapter.

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

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

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

    6. In the Sec. 172.101 Hazardous Materials Table, the following 
entry is added in appropriate alphabetical order:


Sec. 172.101  Purpose and use of hazardous materials table.

* * * * *

[[Page 44382]]



                                                                           Section 172.101.--Hazardous Materials Table                                                                          
                                                                                                                                                                                                
                                                                                                        (8) Packaging authorizations       (9) Quantity limitations         (10) Vessel stowage 
                Hazardous materials   Hazard                                                                   (Sec.  173.***)       ------------------------------------      requirements     
    Symbols       descriptions and   class or    Identification          PG         Label     Special  ------------------------------                                    -----------------------
                  proper shipping    division        numbers                        codes   provisions                Non-                Passenger      Cargo aircraft                         
                       names                                                                            Exceptions    bulk     Bulk     aircraft/rail         only           Location     Other 
(1)             (2)................       (3)  (4)...............  (5)...........      (6)         (7)        (8A)     (8B)     (8C)  (9A)............  (9B)............  (10A)........    (10B)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                
                                       *                  *                  *                  *                  *                  *                  *                                      
+               Oxygen generator,           9  NA3356............  III...........        9          61        None      213     None  Forbidden.......  Forbidden.......  A............         
                 chemical, spent.                                                                                                                                                               
                                                                                                                                                                                                
                                       *                  *                  *                  *                  *                  *                  *                                      
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 44383]]

Sec. 172.101  [Amended]

    7. In addition, in the Sec. 172.101 Hazardous Materials Table, 
Column (9A) is amended by removing the existing language and adding the 
word ``Forbidden'' for the following entries:

Aluminum nitrate
Ammonium dichromate
Ammonium nitrate fertilizers
Ammonium nitrate fertilizers; uniform non-segregating mixtures of 
ammonium nitrate with added matter which is inorganic and chemically 
inert towards ammonium nitrate, with not less than 90 percent 
ammonium nitrate and not more than 0.2 percent combustible material 
(including organic material calculated as carbon), or with more than 
70 percent but less than 90 percent ammonium nitrate and not more 
than 0.4 percent total combustible material
Ammonium nitrate mixed fertilizers
Ammonium nitrate, with not more than 0.2 percent of combustible 
substances, including any organic substance calculated as carbon, to 
the exclusion of any other added substance
Ammonium perchlorate (PG II)
Ammonium persulfate
Barium bromate
Barium chlorate
Barium hypochlorite with more than 22 percent available chlorine
Barium nitrate
Barium perchlorate
Barium permanganate
Barium peroxide
Beryllium nitrate
Bromate, inorganic, aqueous solution, n.o.s.
Bromate, inorganic, n.o.s.
Calcium chlorate
Calcium chlorate aqueous solution
Calcium chlorite
Calcium hypochlorite, dry or Calcium hypochlorite mixtures dry  with 
more than 39 percent available chlorine (8.8 percent available 
oxygen)
Calcium hypochlorite, hydrated or Calcium hypochlorite, hydrated 
mixtures, with not less than 5.5 percent but not more than 10 
percent water
Calcium hypochlorite mixtures, dry, with more than 10 percent but 
not more than 39 percent available chlorine
Calcium nitrate
Calcium perchlorate
Calcium permanganate
Calcium peroxide
Cesium nitrate or Caesium nitrate
Chlorate and borate mixtures (PG II and III)
Chlorate and magnesium chloride mixtures (PG II and III)
Chlorates, inorganic, aqueous solution, n.o.s.
Chlorates, inorganic, n.o.s.
Chlorites, inorganic, n.o.s.
Chromic acid, solid
Chromium nitrate
Chromium trioxide, anhydrous
Compressed gas, oxidizing, n.o.s.
Copper chlorate
Corrosive liquids, oxidizing, n.o.s. (PG II)
Corrosive solids, oxidizing, n.o.s. (PG I and II)
Dichloroisocyanuric acid, dry or Dichloroisocyanuric acid salts
Didymium nitrate
Ferric nitrate
Guanidine nitrate
Hydrogen peroxide and peroxyacetic acid mixtures, stabilized  with 
acids, water and not more than 5 percent peroxyacetic acid
Hydrogen peroxide, aqueous solutions  with not less than 8 percent 
but less than 20 percent hydrogen peroxide (stabilized as necessary)
Hydrogen peroxide, aqueous solutions  with not less than 20 percent 
but not more than 40 percent hydrogen peroxide (stabilized as 
necessary)
Hypochlorites, inorganic, n.o.s.
Lead dioxide
Lead nitrate
Lead perchlorate, solid
Lead perchlorate, solution
Liquefied gas, oxidizing, n.o.s.
Lithium hypochlorite, dry or Lithium hypochlorite mixtures, dry
Lithium nitrate
Lithium peroxide
Magnesium bromate
Magnesium chlorate
Magnesium nitrate
Magnesium perchlorate
Magnesium peroxide
Manganese nitrate
Medicines, oxidizing substance, solid n.o.s.
Nickel nitrate
Nickel nitrite
Nitrates, inorganic, aqueous solution, n.o.s. (PG II and III)
Nitrates, inorganic, n.o.s. (PG II and III)
Nitrites, inorganic, aqueous solution, n.o.s. (PG II and III)
Nitrites, inorganic, n.o.s.
Nitrous oxide, compressed
Oxidizing liquid, corrosive, n.o.s. (PG II and III)
Oxidizing liquid, n.o.s. (PG I, II and III)
Oxidizing liquid, toxic, n.o.s. (PG II and III)
Oxidizing solid, corrosive, n.o.s. (PG I, II and III)
Oxidizing solid, n.o.s. (PG I, II, and III)
Oxidizing solid, toxic, n.o.s. (PG I, II, and III)
Oxygen, compressed
Perchlorates, inorganic, aqueous solution, n.o.s. (PG II and III)
Perchlorates, inorganic, n.o.s. (PG II and III)
Permanganates, inorganic, aqueous solution, n.o.s.
Permanganates, inorganic, n.o.s. (PG II and III)
Peroxides, inorganic, n.o.s. (PG II and III)
Persulfates, inorganic, aqueous solution, n.o.s.
Persulfates, inorganic, n.o.s.
Potassium bromate
Potassium chlorate
Potassium chlorate, aqueous solution (PG II and III)
Potassium nitrate
Potassium nitrate and sodium nitrite mixtures
Potassium nitrite
Potassium perchlorate, solid
Potassium perchlorate, solution
Potassium permanganate
Potassium persulfate
Silver nitrate
Sodium bromate
Sodium chlorate
Sodium chlorate, aqueous solution (PG II and III)
Sodium chlorite
Sodium nitrate
Sodium nitrate and potassium nitrate mixtures
Sodium nitrite
Sodium perchlorate
Sodium permanganate
Sodium peroxoborate, anhydrous
Sodium persulfate
Strontium chlorate
Strontium nitrate
Strontium perchlorate
Strontium peroxide
Thallium chlorate
Thallium nitrate
Toxic liquids, oxidizing, n.o.s. (PG II)
Toxic solids, oxidizing, n.o.s. (PG I and II) mono- (Trichloro) 
tetra-(monopotassium dichloro)-penta-s-triazinetrione, dry (with 
more than 39 percent available chlorine)
Trichloroisocyanuric acid, dry
Urea hydrogen peroxide
Zinc ammonium nitrite
Zinc bromate
Zinc chlorate
Zinc nitrate
Zinc permanganate
Zinc peroxide
Zirconium nitrate


Sec. 172.101  [Amended]

    8. In addition, in the Sec. 172.101 Hazardous Materials Table, for 
the entry ``Oxygen, compressed'', in Column (7), special provision 
``A52'' is added.
    9. In Sec. 172.102, special provision ``61'' is added in 
appropriate numerical sequence to paragraph (c)(1) and special 
provision ``A52'' is added in appropriate alphanumerical sequence to 
paragraph (c)(2), to read as follows:


Sec. 172.102  Special provisions.

* * * * *
    (c) * * *
    (1) * * *

Code/Special Provisions

* * * * *
    61  A chemical oxygen generator is spent if its means of 
ignition and its chemical core have been expended.
* * * * *
    (2) * * *

Code/Special Provisions

* * * * *
    A52  Oxygen, compressed, may be offered for transportation and 
transported on a passenger-carrying aircraft in accordance with the 
provisions of Sec. 175.10(a)(7), (a)(14), or (b) of this subchapter.
* * * * *

PART 175--CARRIAGE BY AIRCRAFT

    9a. The authority citation for part 175 continues to read as 
follows:

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

    10. In Sec. 175.10, paragraph (b) is added to read as follows:

[[Page 44384]]

Sec. 175.10  Exceptions.

* * * * *
    (b) A cylinder containing compressed oxygen, belonging to an 
aircraft operator or a passenger needing the oxygen for personal 
medical use at destination, may be carried in the cabin of a passenger-
carrying aircraft in accordance with procedures approved by the FAA and 
specified in the carrier's operations specifications, manual or plan, 
as appropriate, and the following provisions:
    (1) No more than six cylinders belonging to the aircraft operator 
and, in addition, no more than one cylinder (with a rated oxygen 
capacity of 850 liters (30 cubic feet) or less) per passenger needing 
the oxygen, may be transported on an aircraft under the provisions of 
paragraph (b);
    (2) Each cylinder must conform to the provisions of this subchapter 
with regard to packaging specifications, fill limits, maintenance 
requirements, marking and labeling;
    (3) Each cylinder shall be examined by the aircraft operator to 
ensure that all valves are closed and the cylinder is free of flammable 
contaminants on all exterior surfaces;
    (4) Each cylinder shall be placed in a metal or plastic overpack 
which--
    (i) Is capable of meeting the self extinguishing requirements of 14 
CFR 25.853;
    (ii) Provides protection to the cylinder and valves;
    (iii) Is marked ``Oxygen, Compressed'', ``UN1072'', and ``Passenger 
cabin acceptable per 49 CFR 175.10''; and
    (iv) Is labeled Cargo Aircraft Only and either Oxygen or Non-
Flammable Gas and Oxidizer, in accordance with subpart D of part 172 of 
this subchapter;
    (5) The aircraft operator shall securely stow the overpack in the 
cabin of the aircraft in accordance with the operator's operations 
procedures and shall notify the pilot-in-command as specified in 
Sec. 175.33; and
    (6) Shipments under this paragraph (b) are not subject to--
    (i) The prohibition in Sec. 172.101 of this subchapter against 
carriage of compressed oxygen on passenger-carrying aircraft;
    (ii) Subpart C and, for passengers only, subpart H of part 172 of 
this subchapter;
    (iii) Section 173.25 of this subchapter; or
    (iv) Section 175.85.


Sec. 175.10  [Amended]

    11. In addition in Sec. 175.10, in paragraph (a)(7) the wording ``a 
passenger'' in the first sentence is revised to read ``an onboard 
passenger'' and paragraph (a)(24) is removed and reserved.
    12. In Sec. 175.85, paragraph (b) is revised to read as follows:


Sec. 175.85  Cargo location.

* * * * *
    (b) Each package bearing a Cargo Aircraft Only label or which 
otherwise contains a hazardous material acceptable only for cargo 
aircraft must be loaded in such a manner that a crew member or other 
authorized person can see, handle and when size and weight permit, 
separate such packages from other cargo during flight.
* * * * *

    Issued in Washington, DC on August 12, 1997, under the authority 
delegated in 49 CFR part 106.
A.I. Roberts,
Associate Administrator for Hazardous Materials Safety.
[FR Doc. 97-21739 Filed 8-19-97; 8:45 am]
BILLING CODE 4910-60-P