In 2003, PHMSA also initiated a study with MSU to compare the HMR requirements and the testing used in the FAA/MSU Study discussed previously. To provide for a more thorough evaluation of the performance of liquid hazardous materials combination packagings, this phase of testing was conducted on a smaller number of packaging designs; however, a much greater number of packagings of each design were tested in this study. In the 2002 FAA/MSU study, two packagings of each design were tested; for this study, PHMSA tested thirty packagings from each of eleven designs. With the exception of three packaging designs, all of the packagings tested during this phase had been tested for the 2002 FAA/MSU study. See Table 2 below. A copy of this report is available for review in the public docket.
Table 2.Ranking of Conditions
Percentage of failures of Conditions packages tested Random vibration and vacuum, vertical orientation 12 (conforming to HMR), 14,000 ft, one hour...............
Random vibration and vacuum, horizontal orientation, 18 14,000 ft, one hour....................................
Vacuum only, 95 kPa for 30 min, inverted orientation.... 13 Random vibration, one hour.............................. 11

Average failure rate................................ 13

The conclusions from this testing supported MSU's previous testing conducted for FAA:

E. PHMSA Review of Incident Data

During the first half of 2007, PHMSA conducted a comprehensive assessment of hazardous materials transportation incidents occurring in air transportation from 1997 through 2006. This study and its corresponding data may be accessed in the public docket for this rulemaking. The study concluded that there has been no appreciable reduction in package failures over the past 10 years. It is estimated that 191,429 tons of liquid hazardous materials are transported by aircraft annually contained in 7,657,152 combination packaging shipments. Of that total, our analysis concluded that out of approximately 483 failures (.00006%) in air transportation involving combination packagings containing liquids each year, 20 are reported as ``serious.'' An incident is considered serious if it involves one or more of the following: (1) A fatality or major injury caused by the release of a hazardous material; (2) the evacuation of 25 or more persons as a result of release of a hazardous material or exposure to fire; (3) a release or exposure to fire which results in the closure of a major transportation artery; (4) the alteration of an aircraft flight plan or operation; (5) the release of radioactive materials from Type B packaging; (6) the release of over 45 liters (11.9 gallons) or 40 kilograms (88.2 pounds) of a severe marine pollutant; and (7) the release of a bulk quantity (over 450 liters (119 gallons) or 400 kilograms (882 pounds)) of a hazardous material. We want to emphasize that any incident, such as a package failure, involving hazardous materials in air transportation is unacceptable. In air transportation, any incident could quickly escalate and result in irreversible, possibly catastrophic, consequences.

Accounting for approximately 80 percent of all packages transported by air, combination packagings containing liquids are involved in 44 percent (483) of all package failures annually. Inner packaging closure failures within a combination outer packaging are the primary cause of incidents involving combination packagings in air transportation. Such failures could be the result of pressure differential (packages closed at sea level subjected to lower pressure on planes), ``backing off'' of the closure (closures that appear tight but loosen during
transportation), improper closures, or some other cause. Our analysis also suggests that most incidents involve combination packagings that contain flammable liquids (e.g., paint and paint related material) of varying degrees of hazard. Some additional statistical data from the 2007 incident review include:

PHMSA presented the results of this review at a June 21, 2007 meeting with stakeholders to discuss air packaging issues. The 44 participants included cargo and passenger air carriers, packaging manufacturers and testing laboratories, FAA and PHMSA personnel, and representatives of industry trade associations. The shippers, air carriers, and enforcement personnel present generally agreed that the current capability requirements for air packagings are difficult to comply with and suggested that specific test methods designed to demonstrate that packagings will withstand the air transportation environment should be specified in the HMR.

Stakeholders at the meeting also suggested that increased outreach through industry partnership and targeted enforcement for habitual offenders would significantly enhance achievement of PHMSA and FAA safety goals without additional regulation.

IV. Purpose of This ANPRM

As previously noted, to enhance aviation safety, PHMSA and FAA are seeking to identify costeffective solutions that can be implemented to reduce incident rates and potentially detrimental consequences without placing unnecessary burdens on the regulated community. We are soliciting comments on how to accomplish these goals, including measures to: (1) Enhance the effectiveness of performance testing for packagings used to transport hazardous materials on aircraft; (2) more clearly indicate the responsibilities of shippers that offer packages for air transport in the HMR; and (3) authorize alternatives for enhancing package integrity. Based on PHMSA and FAA analyses, it appears that some combination packaging designs used to transport hazardous materials by aircraft may not meet the pressure differential and vibration capability standards mandated under the HMR. Indeed, the testing suggests that the capability standards themselves may not be sufficiently rigorous to ensure that packagings maintain their integrity under conditions normally incident to air transportation. Because aircraft accidents caused by leaking or breached hazardous materials packages can have significant consequences, the air transport of hazardous materials requires exceptional care and attention to detail. Therefore, we are considering measures to reduce the incidence of package failures and to minimize the consequences of failures should they occur.

The fact that specific test methods are not specified in the HMR or the ICAO Technical Instructions leads to inconsistencies in package integrity and results in varying levels of compliance among shippers. For example, we understand that, because the pressure differential and vibration capability standards for combination packagings are not required to be verified by a test
[[Page 38366]]
protocol, some shippers (selfcertifiers) or manufacturers have used historical shipping data, computer modeling, analogies to tested packagings, engineering studies, or similar methods to determine that their packagings meet pressure differential and vibration capability standards. Further, some less experienced shippers or manufacturers may not understand that their packagings must withstand pressure differential and vibration requirements. In addition, some shippers or manufacturers may not realize that both UN Standard packaging and packagings that are not required to be certified as meeting a specification or standard are subject to the pressure differential capability requirement. This would include packagings for products, such as limited quantities and consumer commodities, where non specification packagings are authorized. A significant percentage of aircraft incidents involving hazardous materials appear to result from failures of nonspecification packagings.

As indicated above, a nonspecification packaging is not required to meet specific performance requirements. Rather, a nonspecification packaging must meet general packaging requirements and, for air transportation, must be capable of withstanding pressures encountered at altitude. We invite comments on how to enforce this ``capability'' standard for nonspecification packagings and ask whether a test of some sort should be required to verify packaging integrity.

A complicating factor that appears to be contributing to packaging failures and noncompliance is that assembly of packages in some cases is not consistent with the design type that was originally tested. In some cases, manufacturers change components without informing the shipper; in other cases, shippers specify or change components without appropriate verification and testing to determine compliance with the applicable performance standard. The numerous variables that exist in the interaction of closures, liners, and container neck finishes preclude the use and validity of general assumptions about equivalent pressure performance capabilities of similar containers.

As an alternative to regulation, the FAA implemented an aggressive public outreach program over the past seven years targeted at specific stakeholder audiences, including thousands of shippers, packaging laboratories, industry research and training institutes, airline operators, and chemical manufacturers. In addition, several voluntary industry standards (test protocols) were either created or revised as a result of the public (independent) and private funding of the studies detailed in the previous sections above. A copy of the report listing the specific public outreach efforts conducted by FAA on this issue can be found in the docket for this rulemaking.

Some regulatory solutions under consideration in this rulemaking process are explained in more detail in the following sections. A. Design Qualification and Periodic Retesting
(1) Pressure differential test. Currently in the HMR, all packagings containing liquids and intended for transport by air must be capable of withstanding, without leakage, an internal gauge pressure of at least 75 kPa for liquids in Packing Group III of Class 3 or 6.1 or 95 kPa for all other liquids, or a pressure related to the vapor pressure of the liquid to be conveyed, whichever is greater (see 49 CFR 173.27(c)). This requirement is also applicable to liquids excepted from specification or UN Standard packaging, such as those authorized for limited quantities and consumer commodities. This would include eligible liquids of Classes 3 (flammable) and 8 (corrosive), and Divisions 5.1 (oxidizer), 5.2 (organic peroxide), and 6.1 (poisonous). Liquids contained in inner receptacles that do not meet the minimum pressure requirements in the current Sec. 173.27(c) may be overpacked into receptacles that do meet the pressure requirements.

In this ANPRM, we are soliciting comments on whether we should require mandatory pressure differential testing for all specification or UN Standard combination packaging designs containing liquids transported or intended for transportation aboard aircraft. In addition, because many incidents are attributed to nonspecification package failures, we are soliciting comments on potential solutions to this problem that may or may not include the mandatory pressure differential testing of inner receptacles intended to contain liquids. One approach would be to incorporate by reference a number of acceptable test methods and to simplify the regulations by removing the requirement for calculating the test pressure in Sec. 173.27(c). Shippers (offerors) would be responsible for using inner receptacles that have been certified as passing one of the following test methods: Test Equipment Time under pressure Pressure differential (a) 49 CFR 178.605................... Pressure fitting, pump. 5 minutes for metal and 60 kPa differential. composite (including glass, porcelain, or stoneware); 30 minutes for plastic. (b) ASTM D665301.................... Vacuum chamber and 60 minutes............. 14,000 ft (41.8 kPa associated gages and differential) \1\ or pumps. 16,000 ft (46.4 kPa differential).\2\ (c) ASTM D499194.................... Transparent vessel 30 minutes for plastic, 60 kPa pressure capable of 10 minutes for differential. withstanding 1\1/2\ everything else. atmospheres, inlet
tube and vacuum pump, moisture trap,
solution of ethylene glycol in water.
(d) ASTM F1140 or Part 178 Appendix D Inlet tube............. 30 minutes............. 60 kPa pressure for flexible packaging. differential. \1\ If it is not possible to use the atmospheric and temperature preconditioning specified. \2\ For test specimens where the atmospheric and temperature preconditioning is followed. (a) 49 CFR 178.605Low Pressure Hydrostatic Pressure Test Method Suitable for Air Inner Packages. This test is currently required for all single and composite packagings intended to contain liquid, but it is not currently required for inner packagings of combination packaging. This test, which uses the hydrostatic test method, pumps highpressure water into a packaging to create a pressure differential. Failure is determined if there is leakage of liquid
[[Page 38367]]
from the package during the test. This could be observed as a stream of liquid exiting the package or rupture of the package.
(b) ASTM D665301Standard Test Methods for Determining the Effects of High Altitude on Packaging Systems by Vacuum Method. This method uses a vacuum chamber to determine the effects of pressure differential on packages. Upon completion of the test, the package is removed and checked for damage in the form of package failure, closure failure, material failure, internal packaging failure, product failure, or combinations thereof. If these are all free of damage, then the packaging should be reassembled for testing in accordance with an industry accepted packaged product performance test, such as Practice D 4169. This will help determine if the pressure differential conditioning had an effect on the performance of the packaging system. (c) ASTM D499194 (Reapproved 1999) Standard Test Method for Leakage Testing of Empty Rigid Containers by Vacuum Method. This test is applied to empty packagings to check for resistance to leakage under differential pressure conditions, such as those that can occur during air transport. Instead of pumping highpressure air into the packaging, the air pressure on the exterior of the packaging is reduced using a vacuum. The package is considered to fail if it leaks a continuous stream or recurring succession of bubbles or if fluid is found within the test specimen after the test.
(d) ASTM F 1140Standard Test Methods for Internal Pressurization Failure Resistance of Unrestrained Packages for Medical Applications. This test applies to flexible packaging (e.g., bags).
(2) Vibration testing. When packages travel through the transportation and distribution environment, they are subject to vibration by automated sorting systems and during transit aboard aircraft, railcars, or trucks. As packages move on conveyor systems during automated sorting, they experience a low level of vibration at a constant frequency. Aircraftinduced vibration typically is very high frequency and low amplitude for 30 minutes to 12 hours on domestic shipments, depending on origin, destination, and the carrier's network. Vibration on trucks occurs at lower frequencies, but at much higher amplitudes than on aircraft. This duration can last anywhere from 5 minutes to several days depending upon the route and the distance from origin to destination. Vibrations from these various sources can result in damage, including scuffing, abrasion, loosening of fasteners and closures, and package fatigue. There are two main types of vibration testing used for packages: Fixed frequency vibration and random vibration. Random vibration provides the most realistic representation of actual transport conditions, but requires equipment that is more expensive.

The HMR require nonbulk packagings to be capable of withstanding, without rupture or leakage, the vibration test in 49 CFR 178.608. In this ANPRM, we are soliciting comments concerning whether the HMR should be revised to require all specification or UN Standard combination packaging design types containing liquids transported or intended to be transported aboard aircraft to be vibration tested and whether alternative vibration test methods should be authorized for nonbulk packagings. We invite comments on whether the random vibration encountered during the ``sorting'' process and multiple flight segments of today's expedited shipping environment contributes to package failure and whether more representative vibration test methods should be specified in the HMR.

Alternative test methods for determining package vibration capability are described in the following table:
Test Title Equipment Frequency Time Vertical Linear Test at Fixed Frequency ASTM D99901 Method A1.......... Repetitive Shock Vibration test Start vibration at Predetermined Test (Vertical machine with 2 Hz and steadily time, as stated Motion). horizontal increase until in applicable surface and the test specimen specification, or mechanism for repeatedly leaves until vertical the test surface. predetermined sinusoidal input; amount of damage fences, is detected. barricades or other restraints. ASTM D99901 Method A2.......... Repetitive Shock Vibration test Start vibration at Predetermined Test (Rotary machine with 2 Hz and steadily time, as stated Motion). horizontal increase until in applicable surface and the test specimen specification, or mechanism for repeatedly leaves until rotational input the test surface. predetermined with a vertical amount of damage component is detected. approximately sinusoidal; fences, barricades or other restraints. ASTM 416904a Paragraph 13.1 Loose Load Use Test Method Use Test Method Assurance Level I: (Schedule F). Vibration ASTM D999, Method ASTM D999, Method 60 min dwell (Repetitive A1 or A2. A1 or A2. time; Assurance Shocks). Level II: 40 min dwell time; Assurance Level

FOR FURTHER INFORMATION CONTACT Michael G. Stevens, Office of Hazardous Materials Standards, Pipeline and Hazardous Materials Safety Administration, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., Washington, DC 205900001, telephone (202) 3668553.