Interpretation Response #98-0139 ([Air Products and Chemicals] [Mr. William R. Fink])
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: Air Products and Chemicals
Individual Name: Mr. William R. Fink
Location State: PA Country: US
View the Interpretation Document
Response text:
DEC 3, 1998
Mr. William R. Fink Ref. No. 98-0139
Packaging Engineer
Air Products and Chemicals
Specialty Gas Department
R.R. #1, P.o. Box 351
Tamaqua, PA 18252
Dear Mr. Fink:
This is in response to your letter, dated June 9, 1998, requesting clarifications of the definition of rare gases and the use of singular or plural form of proper shipping names under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).
Your questions are paraphrased and answered as follows:
Q1. What rare gases are included when describing the proper shipping names "Rare gases and nitrogen mixtures, compressed", "Rare gases and oxygen mixtures, compressedu, and "Rare gases mixtures, compressed"? Does your Office concur with the Compressed Gas Association (CGA) definition of rare gases as specified in the CGA Handbook of Compressed Gases, Third Edition?
AI. Although the CGA Handbook of Compressed Gases is not incorporated by reference in the HMR, this Office agrees that Argon, Helium, Neon, Krypton, and Xenon are rare gases. Also, this position is supported by Table 2-14 of the International Civil Aviation Organization (ICAO) Technical Instructions for the Safe Transport of Dangerous Goods by Air which lists the entry "Rare gases mixture, compressed (e.g. argon; helium; krypton; neon; xenon)u.
Q2. Do you agree with the proper shipping names selected for the gas mixtures described in our four examples?
A2. Section 172.101 provides that the name which most appropriately describes the mixture shall be used. Note that § 172.203(k) (1) provides that all shipping descriptions for poisonous materials for which the proper shipping name does not specifically identify the poisonous constituent shall have the technical name of the constituent entered in parentheses in association with the basic description. Also, § 172.203(k) (2) provides that the technical names of at least two components predominantly contributing to the hazards of a mixture shall be entered in parentheses in association with the basic description.
The following proper shipping names have been selected based on the four scenarios you provided. Examples A and B are proper shipping names only, while Examples C and 0 are proper shipping names and required additional information specified in
§§ 172.202(k) (3) and 172.203(m) (3), respectively.
| Example | Components | Shipping Name |
| A | 1% xenon 10% neon 89% nitrogen |
Rare gases and nitrogen, compressed |
| B | 1% xenon 99% nitrogen |
Rare gas and nitrogen, compressed |
| C | 1% fluorine 10% neon, 9% krypton 71% helium |
Compressed gases, n.o.s. (helium, neon) |
| D | 10% fluorine 10% neon 9% krypton 71% helium |
Compressed gases, toxic, n.o.s. (fluorine, helium) Inhalation Hazard Zone |
Fluorine, compressed is listed by name in the § 172.101 Table and is identified as poisonous by inhalation in hazard zone A, as referenced by Special Provision 1 in column 7. The hazard zone for a mixture of fluorine and other components is determined from the criteria in § 173.116(a), based on the LC50 calculated using the formula in § 173.133(b) (1) (i). The CGA publication, Pamphlet P-20, Standards for Classification of Toxic Gas Mixtures", lists Fluorine in pure form as having an Le50 of 185 parts per million. A gas mixture with a concentration of fluorine greater than or equal to 6.17%, but less than 18.50%, would be described as an inhalation hazard zone C. Therefore, the gas mixture you describe in Example 0, containing 10% fluorine, would be described as an inhalation hazard zone C, and not A, as you indicated. Although not incorporated by reference in the HMR, this Office takes no exception to the criteria in CGA Pamphlet P-20 relative to the classification of toxic gas mixtures.
Q3. Are we permitted to use the singular or plural form of the various "rare gases" proper shipping names when describing these mixtures?
A3. Section 171.101(c} (1) authorizes the use of proper shipping names in the singular or plural. For example, the § 172.101 Table lists the entry, "Rare gases and oxygen mixture". A mixture containing a single rare gas and oxygen would be described as "Rare gas and oxygen mixture".
I hope this satisfies your inquiry. If you need additional assistance please do not hesitate to contact us.
Sincerely,
Hattie L. Mitchell, Chief
Regulatory Review and Reinvention
Office of Hazardous Materials Standards
172.101R