Document ID: FAA-2012-0311-0001
Agency: faa
Document Type: Rule
Title: Special Conditions: Boeing Model 787 Series Airplanes; Single-place Side-facing Seats with Inflatable Lapbelts
Posted Date: 2012-03-23T04:00Z

[Federal Register Volume 77, Number 57 (Friday, March 23, 2012)]
[Rules and Regulations]
[Pages 16910-16914]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-6957]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2012-0311; Special Conditions No. 25-458-SC]

Special Conditions: Boeing Model 787 Series Airplanes; Single-
place Side-facing Seats With Inflatable Lapbelts

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for the Boeing Model 787 
series airplanes. These airplanes have a novel or unusual design 
feature associated with single-place side-facing seats with inflatable 
lapbelts. The applicable airworthiness regulations do not contain 
adequate or appropriate safety standards for this design feature. These 
special conditions contain the additional safety standards that the 
Administrator considers necessary to establish a level of safety 
equivalent to that established by the existing airworthiness standards.

DATES: The effective date of these special conditions is March 12, 
2012. We must receive your comments by April 23, 2012.

ADDRESSES: Send comments identified by docket number FAA-2012-0311 
using any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/ and follow the online instructions for sending 
your comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC, 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE., Washington, DC, between 8 a.m. and 5 p.m., 
Monday through Friday, except federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: The FAA will post all comments it receives, without change, to 
http://www.regulations.gov/, including any personal information the 
commenter provides. Using the search function of the docket Web site, 
anyone can find and read the electronic form of all comments received 
into any FAA docket, including the name of the individual sending the 
comment (or signing the comment for an association, business, labor 
union, etc.). DOT's complete Privacy Act Statement can be found in the 
Federal Register published on April 11, 2000 (65 FR 19477-19478), as 
well as at http://DocketsInfo.dot.gov/.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except federal holidays.

FOR FURTHER INFORMATION CONTACT: Jeff Gardlin, FAA, Airframe and Cabin 
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft 
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-2136; facsimile 425-227-1149.

SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and 
opportunity for prior public comment on, these special conditions are 
impracticable because these procedures would significantly delay 
delivery of the affected aircraft. In addition, the substance of these 
special conditions has been subject to the public-comment process in 
several prior instances with no substantive comments received. The FAA 
therefore finds that good cause exists for making these special 
conditions effective upon issuance.

Comments Invited

    We invite interested people to take part in this rulemaking by 
sending written comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data.
    We will consider all comments we receive by the closing date for 
comments. We may change these special conditions based on the comments 
we receive.

Background

    On March 28, 2003, Boeing Commercial Airplanes applied for an FAA 
type certificate for its new Model 787 series airplane (hereafter 
referred to as ``787''). The 787 is an all-new, twin-engine jet 
transport airplane with a two-aisle cabin which is currently approved 
under Type Certificate No. T000215E. The maximum takeoff weight is 
476,000 pounds, with a maximum passenger count of 381. These airplanes 
have a novel or unusual design feature associated with single-place 
side-facing seats with inflatable lapbelts. The inflatable lapbelt is 
designed to limit occupant forward excursion in the event of an 
accident. This will reduce the potential for head injury, thereby 
reducing the Head Injury Criteria (HIC) measurement. The inflatable 
lapbelt behaves similarly to an automotive airbag, but in this case the 
airbag is integrated into the lapbelt, and inflates away from the 
seated occupant. While airbags are now standard in the automotive 
industry, the use of an inflatable lapbelt is novel for commercial 
aviation.
    Title 14, Code of Federal Regulations (14 CFR) 121.311(j) requires 
that no person may operate a transport category airplane type 
certificated after January 1, 1958, and manufactured on or after 
October 27, 2009, in passenger-carrying operations, after October 27, 
2009, unless all passenger and flight attendant side-facing seats on an 
airplane operated under part 121 rules meet the

[[Page 16911]]

requirements of 14 CFR 25.562 in effect on or after June 16, 1988.
    Amendment 25-15 to part 25, dated October 24, 1967, introduced the 
subject of side-facing seats and a requirement that each occupant in a 
side-facing seat must be protected from head injury by a safety belt 
and a cushioned rest that will support the arms, shoulders, head, and 
spine.
    Subsequently, Amendment 25-20 to part 25, dated April 23, 1969, 
clarified the definition of side-facing seats to require that each 
occupant of a seat that makes more than an 18 degree angle with the 
vertical plane containing the airplane centerline, must be protected 
from head injury by a safety belt and an energy absorbing rest that 
will support the arms, shoulders, head, and spine, or by a safety belt 
and shoulder harness that will prevent the head from contacting any 
injurious object. The FAA concluded that an 18-degree angle would 
provide an adequate level of safety based on tests that were performed 
at that time and thus adopted that standard.
    Part 25 was amended June 16, 1988, by Amendment 25-64, to revise 
the emergency landing conditions that must be considered in the design 
of the airplane. Amendment 25-64 revised the static load conditions in 
Sec.  25.561, and added a new Sec.  25.562 that required dynamic 
testing for all seats approved for occupancy during takeoff and 
landing. The intent of Amendment 25-64 is to provide an improved level 
of safety for occupants on transport category airplanes. Because most 
seating is forward-facing on transport category airplanes, the pass/
fail criteria developed in Amendment 25-64 focused primarily on these 
seats. As a result, the FAA issued Policy Memorandums ANM-03-115-30 and 
PS-ANM-100-2000-00123 to provide the additional guidance necessary to 
demonstrate the level of safety required by the regulations for side-
facing seats.
    The 787, operated under part 121, must meet all of the requirements 
of Sec.  25.562 for passenger and flight attendant seats. Therefore it 
is in the interest of installers to show full compliance to Sec.  
25.562, so that an operator under part 121 may be able to use the 
aircraft without having to do additional certification work. It is also 
noted that some foreign civil airworthiness authorities have invoked 
these same operator requirements in the form of airworthiness 
directives.
    Section 25.785 requires that occupants be protected from head 
injury by either the elimination of any injurious object within the 
striking radius of the head, or by padding. Traditionally, this has 
required a set back of 35 inches from any bulkhead or other rigid 
interior feature or, where not practical, specified types of padding. 
The relative effectiveness of these means of injury protection was not 
quantified. With the adoption of Amendment 25-64 to part 25, 
specifically Sec.  25.562, a new standard that quantifies required head 
injury protection was created.
    Section 25.562 specifies that each seat type design approved for 
crew or passenger occupancy during takeoff and landing must 
successfully complete dynamic tests or be shown to be compliant by 
rational analysis based on dynamic tests of a similar type seat. In 
particular, the regulations require that persons not suffer serious 
head injury under the conditions specified in the tests, and that 
protection must be provided or the seat be designed so that the head 
impact does not exceed a HIC of 1000 units. While the test conditions 
described for HIC are detailed and specific, it is the intent of the 
requirement that an adequate level of head injury protection be 
provided for passengers in a severe crash.
    Because Sec. Sec.  25.562 and 25.785 and associated guidance do not 
adequately address side-facing seats with inflatable lapbelts, the FAA 
recognizes that appropriate pass/fail criteria need to be developed 
that do fully address the safety concerns specific to occupants of 
these seats. These criteria were to be implemented via special 
conditions.
    The inflatable lapbelt has two potential advantages over other 
means of head impact protection. First, it can provide significantly 
greater protection than would be expected with energy-absorbing pads, 
and second, it can provide essentially equivalent protection for 
occupants of all stature. These are significant advantages from a 
safety standpoint, since such devices will likely provide a level of 
safety that exceeds the minimum standards of the CFR. Conversely, 
inflatable lapbelts in general are active systems and must be relied 
upon to activate properly when needed, as opposed to an energy-
absorbing pad or upper torso restraint that is passive, and always 
available. Therefore, the potential advantages must be balanced against 
this and other potential disadvantages in order to develop standards 
for this design feature.
    The FAA has considered the installation of inflatable lapbelts to 
have two primary safety concerns: First, that they perform properly 
under foreseeable operating conditions, and second, that they do not 
perform in a manner or at such times as would constitute a hazard to 
the airplane or occupants. This latter point has the potential to be 
the more rigorous of the requirements, owing to the active nature of 
the system.
    The inflatable lapbelt will rely on electronic sensors for 
signaling and a stored gas canister for inflation. These same devices 
could be susceptible to inadvertent activation, causing deployment in a 
potentially unsafe manner. The consequences of inadvertent deployment 
as well as failure to deploy must be considered in establishing the 
reliability of the system. Boeing must substantiate that the effects of 
an inadvertent deployment in flight either would not cause injuries to 
occupants or that such deployment(s) meet the requirement of Sec.  
25.1309(b). The effect of an inadvertent deployment on a passenger or 
crewmember that might be positioned close to the inflatable lapbelt 
should also be considered. The person could be either standing or 
sitting. A minimum reliability level will have to be established for 
this case, depending upon the consequences, even if the effect on the 
airplane is negligible.
    The potential for an inadvertent deployment could be increased as a 
result of conditions in service. The installation must take into 
account wear and tear so that the likelihood of an inadvertent 
deployment is not increased to an unacceptable level. In this context, 
an appropriate inspection interval and self-test capability are 
considered necessary. Other outside influences are lightning and high 
intensity radiated fields (HIRF). Existing regulations regarding 
lightning, Sec.  25.1316, and existing HIRF special condition for the 
787 series airplanes, Special conditions No. 25-354A-SC, are 
applicable. Finally, the inflatable lapbelt installation should be 
protected from the effects of fire, so that an additional hazard is not 
created by, for example, a rupture of the pyrotechnic squib.
    In order to be an effective safety system, the inflatable lapbelt 
must function properly and must not introduce any additional hazards to 
occupants as a result of its functioning. There are several areas where 
the inflatable lapbelt differs from traditional occupant protection 
systems, and requires special conditions to ensure adequate 
performance.
    Because the inflatable lapbelt is essentially a single use device, 
there is the potential that it could deploy under crash conditions that 
are not sufficiently severe as to require head injury protection from 
the inflatable lapbelt. Since an actual crash is frequently composed of 
a series of impacts before the airplane comes to rest, this could

[[Page 16912]]

render the inflatable lapbelt useless if a larger impact follows the 
initial impact. This situation does not exist with energy absorbing 
pads or upper torso restraints, which tend to provide continuous 
protection regardless of severity or number of impacts in a crash 
event. Therefore, the inflatable lapbelt installation should provide 
protection when it is required, by not expending its protection during 
a less severe impact. Also, it is possible to have several large impact 
events during the course of a crash, but there is no requirement for 
the inflatable lapbelt to provide protection for multiple impacts.
    Since each occupant's restraint system provides protection for that 
occupant only, the installation must address seats that are unoccupied. 
It will be necessary to show that the required protection is provided 
for each occupant regardless of the number of occupied seats, and 
considering that unoccupied seats may have lapbelts that are active.
    The inflatable lapbelt should be effective for a wide range of 
occupants. The FAA has historically considered the range from the fifth 
percentile female to the ninety-fifth percentile male as the range of 
occupants that must be taken into account. In this case, the FAA is 
proposing consideration of a broader range of occupants, due to the 
nature of the lapbelt installation and its close proximity to the 
occupant. In a similar vein, these persons could have assumed the brace 
position, for those accidents where an impact is anticipated. Test data 
indicate that occupants in the brace position do not require 
supplemental protection, and so it would not be necessary to show that 
the inflatable lapbelt will enhance the brace position. However, the 
inflatable lapbelt must not introduce a hazard in that case when 
deploying into the seated, braced occupant.
    Another area of concern is the use of seats, so equipped, by 
children whether lap-held, in approved child safety seats, or occupying 
the seat directly. Although specifically prohibited by the FAA 
operating regulations, the use of the supplementary loop belt (``belly 
belt'') may be required by other civil aviation authorities, and should 
also be considered with the end goal of meeting those regulations. 
Similarly, if the seat is occupied by a pregnant woman, the 
installation needs to address such usage, either by demonstrating that 
it will function properly, or by adding appropriate limitation on 
usage.
    Since the inflatable lapbelt will be electrically powered, there is 
the possibility that the system could fail due to a separation in the 
fuselage. Since this system is intended as crash/post-crash protection 
means, failure to deploy due to fuselage separation is not acceptable. 
As with emergency lighting, the system should function properly if such 
a separation occurs at any point in the fuselage.
    Since the inflatable lapbelt is likely to have a large volume 
displacement, the inflated bag could potentially impede egress of 
passengers. Since the bag deflates to absorb energy, it is likely that 
an inflatable lapbelt would be deflated at the time that persons would 
be trying to leave their seats. Nonetheless, it is considered 
appropriate to specify a time interval after which the inflatable 
lapbelt may not impede rapid egress. Ten seconds has been chosen as a 
reasonable time since this corresponds to the maximum time allowed for 
an exit to be openable (Sec.  25.809). In actuality, it is unlikely 
that an exit would be prepared by a flight attendant this quickly in an 
accident severe enough to warrant deployment of the inflatable lapbelt, 
and the inflatable lapbelt is expected to deflate much quicker than ten 
seconds.
    In addition, during the development of the inflatable lapbelt, the 
manufacturer was unable to develop a fabric that would meet the 
inflation requirements for the bag and the flammability requirements of 
Part I(a)(1)(ii) of appendix F to part 25. The fabrics that were 
developed that meet the flammability requirement did not produce 
acceptable deployment characteristics. However, the manufacturer was 
able to develop a fabric that meets the less stringent flammability 
requirements of Part I(a)(1)(iv) of appendix F to part 25 and has 
acceptable deployment characteristics.
    Part I of appendix F to part 25 specifies the flammability 
requirements for interior materials and components. There is no 
reference to inflatable restraint systems in appendix F, because such 
devices did not exist at the time the flammability requirements were 
written. The existing requirements are based on both material types, as 
well as use, and have been specified in light of the state-of-the-art 
of materials available to perform a given function. In the absence of a 
specific reference, the default requirement would be for the type of 
material used to construct the inflatable restraint, which is a fabric 
in this case. However, in writing special conditions, the FAA must also 
consider the use of the material, and whether the default requirement 
is appropriate. In this case, the specialized function of the 
inflatable restraint means that highly specialized materials are 
needed. The standard normally applied to fabrics is a 12-second 
vertical ignition test. However, materials that meet this standard do 
not perform adequately as inflatable restraints. Since the safety 
benefit of the inflatable restraint is very significant, the 
flammability standard appropriate for these devices should not screen 
out suitable materials, thereby effectively eliminating use of 
inflatable restraints. The FAA will need to establish a balance between 
the safety benefit of the inflatable restraint and its flammability 
performance. At this time, the 2.5-inch per minute horizontal test is 
considered to provide that balance. As the state-of-the-art in 
materials progresses (which is expected), the FAA may change this 
standard in subsequent special conditions to account for improved 
materials.
    Finally, it should be noted that the special conditions are 
applicable to single-place side-facing seats with an inflatable lapbelt 
system installed. The special conditions are not an installation 
approval. Therefore, while the special conditions relate to each such 
system installed, the overall installation approval is a separate 
finding, and must consider the combined effects of all such systems 
installed.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Boeing Commercial Airplanes 
must show that the 787 series airplanes meet the applicable provisions 
of part 25, as amended by Amendments 25-1 through 25-120, 25.125, 25-
125, and 25-128 with the following exception: Sec.  25.1309 remains at 
Amendment 25-119 for cargo fire protection systems.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the 787 series airplanes because of a 
novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same novel or 
unusual design feature, the special conditions would also apply to the 
other model.
    In addition to the applicable airworthiness regulations and special 
conditions, the 787 series airplanes must comply with the fuel vent and 
exhaust emission requirements of 14 CFR part 34 and the noise 
certification requirements of 14 CFR part 36; and the FAA must issue a 
finding of regulatory

[[Page 16913]]

adequacy under Sec.  611 of Public Law 92-574, the ``Noise Control Act 
of 1972.''
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type-
certification basis under Sec.  21.17(a)(2).

Novel or Unusual Design Features

    The 787 series airplanes incorporate the following novel or unusual 
design features: Boeing Commercial Airplanes is installing single-place 
side-facing seats with inflatable lapbelts on certain seats of 787 
series airplanes, in order to reduce the potential for head and neck 
injury in the event of an accident. The inflatable lapbelt works 
similar to an automotive airbag, except that the airbag is integrated 
with the lapbelt of the restraint system.
    The CFR states the performance criteria for head injury protection 
in objective terms. However, none of these criteria are adequate to 
address the specific issues raised concerning single-place side-facing 
seats with inflatable lapbelts. The FAA has therefore determined that, 
in addition to the requirements of part 25, special conditions are 
needed to address requirements particular to installation of single-
place side-facing seats with inflatable lapbelts.
    Accordingly, in addition to the passenger injury criteria specified 
in Sec.  25.785, these special conditions are adopted for the 787 
series airplanes equipped with single-place side-facing seats with 
inflatable lapbelts. Other conditions may be developed, as needed, 
based on further FAA review and discussions with the manufacturer and 
civil aviation authorities.

Discussion

    From the standpoint of a passenger safety system, the inflatable 
lapbelt is unique in that it is both an active and entirely autonomous 
device. While the automotive industry has good experience with airbags, 
the conditions of use and reliance on the inflatable lapbelt as the 
sole means of injury protection are quite different. In automobile 
installations, the airbag is a supplemental system and works in 
conjunction with an upper torso restraint. In addition, the crash event 
is more definable and of typically shorter duration, which can simplify 
the activation logic. The airplane operating environment is also quite 
different from automobiles and includes the potential for greater wear 
and tear, and unanticipated abuse conditions (due to galley loading, 
passenger baggage, etc.); airplanes also operate where exposure to high 
intensity electromagnetic fields could affect the activation system.
    The following special conditions can be characterized as addressing 
either the safety performance of the system, or the system's integrity 
against inadvertent activation. Because a crash requiring use of the 
inflatable lapbelts is a relatively rare event, and because the 
consequences of an inadvertent activation are potentially quite severe, 
these latter requirements are probably the more rigorous from a design 
standpoint.

Applicability

    As discussed above, these special conditions are applicable to the 
787 series airplane. Should Boeing Commercial Airplanes apply at a 
later date for a change to the type certificate to include another 
model incorporating the same novel or unusual design feature, the 
special conditions would apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on 787 series of airplanes. It is not a rule of general applicability.
    The substance of these special conditions has been subjected to the 
notice and comment period in several prior instances and has been 
derived without substantive change from those previously issued. It is 
unlikely that prior public comment would result in a significant change 
from the substance contained herein. Therefore, because a delay would 
significantly affect the certification of the airplane, which is 
imminent, the FAA has determined that prior public notice and comment 
are unnecessary and impracticable, and good cause exists for adopting 
these special conditions upon issuance. The FAA is requesting comments 
to allow interested persons to submit views that may not have been 
submitted in response to the prior opportunities for comment described 
above.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Special Conditions

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type certification basis for Boeing Model 787 series airplanes.
    1. Existing Criteria: All injury protection criteria of Sec.  
25.562(c)(1) through (c)(6) apply to the occupant of a side facing 
seat. Head Injury Criterion (HIC) assessments are only required for 
head contact with the seat and/or adjacent structures.
    2. Body-to-Wall/Furnishing Contact: Under the load condition 
defined in Sec.  25.562(b)(2), the seat must be installed aft of a 
structure such as an interior wall or furnishing that will support the 
pelvis, upper arm, chest, and head of an occupant seated next to the 
structure. A conservative representation of the structure and its 
stiffness must be included in the tests.
    3. Thoracic Trauma: Under the load condition defined in Sec.  
25.562(b)(2), Thoracic Trauma Index (TTI) injury criterion must be 
substantiated by dynamic test or by rational analysis based on previous 
test(s) of a similar seat installation. Testing must be conducted with 
a Side Impact Dummy (SID), as defined by Title 49 Code of Federal 
Regulations (CFR) part 572, subpart F, or its equivalent. TTI must be 
less than 85, as defined in 49 CFR part 572, subpart F. The SID TTI 
data must be processed as defined in Federal Motor Vehicle Safety 
Standard (FMVSS) Sec.  571.214, section S6.13.5.
    4. Pelvis: Under the load condition defined in Sec.  25.562(b)(2), 
pelvic lateral acceleration must be shown by dynamic test or by 
rational analysis based on previous test(s) of a similar seat 
installation to not exceed 130g. Pelvic acceleration data must be 
processed as defined in FMVSS Sec.  571.214, section S6.13.5.
    5. Shoulder Strap Loads: Where upper torso straps (shoulder straps) 
are used for occupants, tension loads in individual straps must not 
exceed 1,750 pounds. If dual straps are used for restraining the upper 
torso, the total strap tension loads must not exceed 2,000 pounds.
    6. Neck Injury Criteria: The seating system must protect the 
occupant from experiencing serious neck injury.

General Test Guidelines

    1. One longitudinal test with the SID Anthropomorphic Test Dummy 
(ATD), undeformed floor, no yaw, and with all lateral structural 
supports (armrests/walls).
    2. Pass/fail injury assessments: TTI and pelvic acceleration. One 
longitudinal test with the Hybrid II ATD, deformed floor, with 10 
degrees yaw, and with all lateral structural supports (armrests/walls). 
Pass/fail injury assessments: HIC, and upper torso restraint load, 
restraint system retention and pelvic acceleration.

[[Page 16914]]

    3. Vertical (14 G's) test is to be conducted with modified Hybrid 
II ATDs with existing pass/fail criteria.

    Note: It must be demonstrated that the installation of seats via 
plinths or pallets meets all applicable requirements. Compliance 
with the guidance contained in FAA Policy Memorandum PS-ANM-100-
2000-00123, dated February 2, 2000, titled ``Guidance for 
Demonstrating Compliance with Seat Dynamic Testing for Plinths and 
Pallets'' will be acceptable to the FAA.

Inflatable Lapbelt Conditions

    If inflatable lapbelts are installed on single-place side-facing 
seats, the inflatable lapbelt(s) must meet the final inflatable lapbelt 
special conditions (Special Conditions No. 25-431-SC (76 FR 35324, June 
17, 2011).

    Issued in Renton, Washington, on March 12, 2012.
John Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service, ANM-100.
[FR Doc. 2012-6957 Filed 3-22-12; 8:45 am]
BILLING CODE 4910-13-P