# Electronic Fluorocarbons — Hazardous Materials Safety Interpretation - **operation:** document - **citation:** 23-0027 - **title:** Electronic Fluorocarbons — Hazardous Materials Safety Interpretation - **source type:** guidance - **agency:** Pipeline and Hazardous Materials Safety Administration - **status:** guidance - **official:** true - **published on:** 2024-02-01 - **effective on:** Not available - **summary:** 23-0027 response to Electronic Fluorocarbons concerning 173.301, 173.40. - **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-23-0027.json - **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-23-0027.md - **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-23-0027 - **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/docs/standards-rulemaking/hazmat/interpretations/78171/230027.pdf **body:** <<>> U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 February 1, 2024 Mr. Jason Bombard, PE Electronic Fluorocarbons 3266 Bergey Road Hatfield, PA 19440 Reference No. 23-0027 Dear Mr. Bombard: This is in response to your March 14, 2023, letter concerning the filling densities of specification cylinders under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). In your letter, you ask about the maximum allowable filling density of a specification cylinder containing a mixture comprised of 30% Fluorine, 60% Nitrogen, and 10% Argon by volume. You state that you offer this mixture using the proper shipping name “UN3306, Compressed gas, toxic, oxidizing, corrosive, n.o.s. Inhalation Hazard Zone B, 2.3, (5.1, 8).” You also note that § 173.301a(d)(3) limits the pressure in a specification cylinder to no higher than its service pressure at 55°C (131°F). You ask whether there is any additional hazard posed by the fluorine content of this mixture that would further limit the service pressure of the specification cylinder. The answer is no. Provided your material is properly classed as “UN3306, Compressed gas, toxic, oxidizing, corrosive, n.o.s. Inhalation Hazard Zone B, 2.3, (5.1, 8),” the pressure in a specification cylinder at 55°C (131°F) must be limited to the service pressure of the cylinder in accordance with §§ 173.301a(d)(3) and 173.40(b). Please note that sufficient outage must be provided so that the cylinder will not be liquid full at 55°C (131°F). I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, T. Glenn Foster Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division <<>> 3266 Bergey Road Hatfield, PA 19440 Phone: 215.443.9600 Fax: 888-817-7161 www.efgases.com 23-0027 Andrews Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 March 14, 2023 Interpretation of 49 CFR Dear Sir or Madam: I am writing to ask for an interpretation of 49 CFR regarding the maximum allowable filling density of a 30% F2, 60% N2, 10% Ar mixture by volume. This is shipped as UN3306: Compressed Gas, Toxic, Oxidizing, Corrosive, N.O.S. with a Zone B hazard classification. 173.301a(d)(3) limits the pressure in the cylinder to no higher than its service pressure at 55 °C (131 °F). Is there any additional hazard posed by the fluorine content that would further limit this? Thank you for your help with this. If you have any questions or I can provide any clarification, please do not hesitate to contact me. Best regards, Jason Bombard, PE 215-443-9600 X 123 jbombard@efgases.com - **truncated:** false - **body characters:** 2736