Mr. Charles E. Tudor — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue. SE Washington, D.C. 20590 MAY 0 7 2012 Mr. Charles E. Tudor, CP-P/MH 12419 Entiat River Road Entiat, W A 98822 Reference No.: 12-0038 Dear Mr. Tudor: This responds to your January 23, 2012letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the packaging of nitrous oxide in non-specification cylinders. In your incoming letter, you describe a scenario in which your client intends to ship 7.5 grams of nitrous oxide in a 10-ml non-specification cylinder via air and vessel internationally. These nitrous oxide non-specification cylinders are to be used in medical devices. Based on this scenario, your questions are paraphrased and answered as follows: Ql. Is nitrous oxide permitted to be transported in 10-ml non-specification cylinders for domestic and international air transport? Al. The answer is no. The Column 7 entry in the Hazardous Materials Table (HMT; § 172.101) for "UN 1070, Nitrous Oxide" lists Special Provision A14. Special Provision A14 states that nitrous oxide is not authorized to be transported as a limited quantity in accordance with§ 173.306 when transported by aircraft. Therefore, nitrous oxide, when transported by air, must comply with the requirements specified in either§§ 173.304,173.314, or 173.315. Specifically, § 173.304(t) provides the authorized specification cylinders permitted, filling requirements, and outer packaging requirements for the air transport of oxidizers, including nitrous oxide. Nitrous oxide would only be permitted to be shipped by aircraft in a non-specification cylinder if the shipment utilized a special permit. It should be noted that nitrous oxide transported by highway, rail or vessel meeting the limited quantities for compressed gas requirements specified in § 173.306 may be transported in non-specification cylinders. Q2. If nitrous oxide is permitted to be transported in 10-ml non-specification cylinders for domestic arid international air transport, what filling limits should be used? A2. As noted above, nitrous oxide is not permitted to be shipped in 10-ml non- specification cylinders by air unless a special permit is issued providing relief from the requirements of the HMR. Furthermore, as specified in the table in § 173.304a(a)(2), nitrous oxide has a maximum filling density of 68% when transported in accordance with the HMR. Shipments transported under the#

Page 2Q3. A3. Q4. A4. Q5. A5. Q6. A6. Q7. International Civil Aviation Organization's Technical Instructions (ICAO TI) must comply with the filling limits listed in packing instruction (PI) 200. Does USG 18 and § 173.304(t) apply to air shipments of nitrous oxide? The answer is yes. For air shipments of nitrous oxide transported in the United States, both USG 18 and § 173.304(t) would apply. Does PHMSA require fire-resistant outer packaging on vessel shipments of oxidizers, specifically nitrous oxide? The answer is no. The requirements in§ 173.304(t)(3) requiring a rigid fire-resistant outer packaging are specific to air shipments of oxidizing gases. There is no analogous requirement for vessel transport. Should 10-ml nitrous oxide non-specification cylinders be treated as "articles" and be packaged in accordance with PI 003 as indicated by the International Maritime Dangerous Goods (IMDG) code? In accordance with§ 173.22 and Chapter 2 of the IMDG code, it is the shipper's responsibility to properly class and describe a hazardous material. This Office does not perform that function. However, it is the opinion of this Office that, the scenario you describe, "UN 1 070, Nitrous Oxide" is the most appropriate proper shipping description. Furthermore, under the IMDG code "UN 1 070, Nitrous Oxide" should be packaged in accordance with PI 200. If the 10-ml nitrous oxide non-specification cylinders are to be treated as "articles" are they required to be packaged in combination packagings that have been UN performance tested? As stated in A5, it is the opinion of this Office that in the scenario you describe "UN 1070, Nitrous Oxide" is the most appropriate proper shipping description. Therefore, for vessel transport under the HMR, the nitrous oxide could be packaged in accordance with§§ 173.304, 173.306, 173.314, or 173.315. Under the IMDG code, nitrous oxide should be packaged in accordance with PI 200. Is there an existing special permit covering the nitrous oxide cartridges described above?#

Page 3A7. PHMSA's Approvals and Permits Division has issued special permits authorizing the use of non-specification cylinders for the air transport of nitrous oxide under specific transport conditions and after a technical review of the non-specification cylinder. Based on the schematic drawing you provided in your incoming letter, it does not appear as if your non-specification cylinder has been issued a special permit. Under § 107.105, you may apply for your own special permit that authorizes air shipment of nitrous oxide in non-specification cylinders. You may contact our Approvals and Permits Division at (202) 366-4535 for more information. I hope this satisfies your inquiry. Please contact us if we can be of further assistance. Sincerely, T. Glenn Foster Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division#

Page 4Office of Hazardous Materials Standards, PHMSA Attn: PHH-1 0 US Department of Transportation, East Building 1200 New Jersey Avenue, SE. Washington DC 20590-0001 Attn: Charles Betts, Division Director Greetings: My specific questions relate to the shipment of nitrous oxide in cartridges, in particular cartridges that are small non-spec cylinders--the same as commonly used for C02 for a myriad of consumer applications. My client wishes to ship 8 ml cartridges internationally as a consumable that is used in a medical device they are developing. The filling limit is 0.75 as per the table in ICAOIIATA (higher than the 0.68 permitted in the CFR at 173.304 table of filling limits). Cartridges of nitrous oxide are in common consumer use as blowing agents for home dispensers of whipped cream, possibly of foreign origin. My client needs the ability to ship the cartridges world wide by air and vessel. They desire to package them in relatively small quantities for distribution to doctors. Question 1. Can these cartridges containing nitrous oxide be offered for domestic/international air transport? If so, can they be filled based on the filling limits table in ICAO and IMDG? Or are they limited to low pressures of aerosols? (See discussion) Question 2. Ifthey can ship by air does USG 18 apply (173.304(f)) to these cartridges? Question 3. Has PHMSA imposed fire resistant outer packaging on vessel shipment of oxidizers? Or more specifically, for cylinders of nitrous oxide? Question 4. Are these cartridges to be treated as "articles'' as is indicated by the IMDG Code use of PI 003 instead of P200? Question 5. If they are articles in combination packaging, are they required to be UN performance tested? Note that the IMDG Code PI 003 does not require UN performance testing. This could result in a miss match for import/export if this were to be used. Question 6. Is there an existing special permit covering these N20 cartridges? Page 1 of3#

Page 5The IMDG Code entry references PI P003. Column 17 of the Table suggests that this entry is for mixtures of propane and butane used in camping stoves. This type of cartridge is low pressure and not what we have here. P003 treats cartridges as "articles", whereas the CFR and ICAO/IATA is rather silent on this. None of the modal regulations define "Receptacles, small containing gas (gas cartridges)". The common everyday C02 cartridge has been around for nearly a hundred years. Its use for other gases is common (I know they are used for helium in addition to nitrous oxide.) It is interesting that the regulations do not specifically recognize these cartridges as a standard package form. Further investigation turned up an interesting special permit SP-7951 that has been in existence for a long time. A specific aerosol can with this permit mark is Land-O-Lakes brand 16 oz., whipped heavy cream by Land-O-Lakes, Inc., distributed by WhiteWave Foods, Broomfield, CO. and purchased at a Costco. The can lists nitrous oxide as the propellant. The permit (issued to ConAgra, Inc.) doesn't mention nitrous oxide and lists authorized shipping names as Compressed gas n.o.s. and Consumer Commodity. The permit also authorizes shipment by cargo and passenger air without mention of DOT 31 FP outer packaging which would seem inconsistent with provisions of the regulations not covered by the permit. This permit has nothing to do with cartridges per se. I have not found a permit that does apply to nitrous oxide cartridges. I have been reading these regulations for 40 years but never had to deal with these critters. So, have I missed something or are the regulations a bit vague on this subject? I look forward to your prompt response. Charles E. Tudor, CP-P/MH HM Packaging Compliance Consultant 12419 Entiat River Road Entiat, W A 98822 Ph.: 509 784 0264 Email: cetudor4143@gmail.com Attachment (2) Page 3 of3#

Page 6DISCUSSION: As I read the regulations for Nitrous oxide, UN 1070 a 2.2 gas with a sub risk of 5.1: "Excepted Quantity" provisions do not apply to air or vessel transport due to sub-risk. Limited Quantity provisions for UN 1070 in the CFR apply only to surface transport. (See Special Provision A14 in the Table.) For domestic surface transport it appears that 173.306(a)(1) would permit shipment as Limited Quantity, but the water is muddied by 1733.306(j) which limits pressure in small receptacles to 970 kPa (141psi) and "containing no HM other than a Division 2.2 gas". Does the sub-risk 5.1 represent "another HM"?? Nitrous oxide is shipped at much higher pressure requiring 1800 psi rated cylinders. 173.304(f) specifically addresses nitrous oxide in air shipment and requires spec cylinders with relief devices and a UN performance tested (PO I, II) fire/heat resistant overpack (DOT 31 FP). Non-spec cartridges or articles are not discussed. There is no Limited Quantity provision for UN 1070 in ICAOIIA TA. PI 200 specifically requires cylinders other than UN marked cylinders to meet the requirements of the national authority of the State where they are approved and filled. (How does one know if there are no marks on them?) PI 200 also requires cylinders of nitrous oxide to have relief devices so if these cartridges are "cylinders" by definition (this is not clear) then they cannot be shipped under this regulation (unless approved by you-the competent authority). If they can be considered cylinders then USG 18 requiring the fire resistant overpack would apparently apply. The only discussion of cartridges specifically in PI 200 is imposing the hot water bath in Section 6.4.4.1. Apparently pressure is not an issue. There is no Limited Quantity provision in the IMDG Code for UN 1070. P200(1) again specifically requires pressure relief devices and does not discuss non-refillable cartridges. Looking further- Considering the PSN "Receptacles, small, containing gas or Gas cartridges (oxidizing) without a release devise, not refillable and not exceeding 1 L capacity,) UN203 7: This description very much describes the shipment. But .... The CFR again references 173.304/.306 and SP A14-back to square one-are cartridges limited to 970 kPa or can they be filled to 0.68/0.75 density per the table?? ICAOIIATA references PI 203 and SP A167 (which invokes the 6.4.4 hot water bath). PI 203 addresses aerosols and gas cartridges but appears to limit the max pressure at 55°C to 1500 kPa (217 psi). This doesn't fit for nitrous oxide. Page 2 of3#

Page 7Component Specification Document Number: 10072 Nitrous Oxide Cylinder, 8 gram Revision: D 7.5 GRAMS N20 / 10 ml FOOD GRADE • CRIMPED CLOSURE ARTICLE No. 0173 PIERCABLE DIAPHIRAGAI _/28.7=0.2 MIN Ø2.5 UNPLATED THICKNESS 0.37/0.43 10m 1== 61013 MASS OF GAS MASSE DE REMPLISSAGE GASMASSE (7.5+0.25g N20 WATER CAPACITY VOLUME (VOLUMEN MIN 10.3ml MIN FULLDICHTE FILLING DENSITY 0.75kg/l DESITE DE REMFLISSAGE MAX MUrDnUCK = INNCNDAUCK DEI TEST PRESSURE = PRESSURE OF CONTENTS AT PRESSION DE CONFOLE : PRESSION INTERNE A 65:5°C 0.75 +0.05 WALL THICKNESS BURST PRESSURE OF CYLINDER PRESSION D'ECLATEMENT DE LA BOUTEILLE HEKSIUKUCK DES ZYEINDEHS 50MPa MIN 65 =0.5 KAPPENANSTECHKRAFT CAP PIERCING FORCE (Si SPEC VIA.P.001X) 450N FORCE DE PERCUTION MAX ARBEIT EEM CURCKSTECHEN DER KAPPE CAF FICACING WORK (SE SPC VIA.Г.001 1) 0.75Nm MAX TEXT LOCATION SUAFACE TREATMENT TRAYAL FOUR LA PERFORATION DU CAPUCHON OBERFLACHENBEHANDLUNG IN ACCORDANCE WITH laquered pink TRAITEMENT DE SURFACE CYLINDER MATERIAL PARTS LIST UNFILLED CYLINDER W-No.1.0338 EN 10139 DC04 CAP MATERAL W-No. 1.0338 EN 10139 C03 0144 Ø18 +0.2 WASHER 0291 NO. SPEC 0198. E9421-99,0% PURITY N20 VIN : NOTES 1. INTERNAL SURFACE SHALL BE CLEAN, DRY AND 2. STORAGE TEMPERATURE LIMIT: MAX +50°C FREE OF RUST AND/OR LOOSE PARTICLES 18T GmbH ALL DRAWING DIMENSIONS IN mm SCALE AM IS GROUP COWPANY 2:1 STAR 01 302-07-10 n. Drg. KPR 8g N20 / 10 ml ZYLINDER NIT BORDELKAPPE L3sue Date Change Name formation or dastriptiva matter not out BOUTEILLE DE 6 0 M2O / 10 ml A CAPUCHOW SEA THIS DRAWING REPLACES must not be diacioané loanad copied or vas harain are castidentini aad enpyright a 0173 (ISSUE: the owners 0173 ISSUE: 01 Proprietary & Confidential Page | 2of 2#