Entegris, Inc. — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 May 6, 2020 Mr. James V. McManus Principal Engineer Dangerous Goods Safety Advisor Entegris, Inc. 7 Commerce Drive Danbury, CT 06810 Reference No. 19-0114 Dear Mr. McManus: This letter is in response to your September 24, 2019, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to empty packagings. Specifically, you ask whether a 50-liter Department of Transportation (DOT) 3AA- 2400 specification cylinder containing “UN 2199, Phosphine, 2.3 (poisonous gas), 2.1 (flammable gas),” residue is subject to the HMR after the cylinder is cleaned of residue and purged of vapors using a vacuum pump and nitrogen purging. You state the 100 ppmv phosphine/nitrogen mixture within the cylinder has a calculated LC50 of 200,000 ppm and the pressure within the cylinder is less than 200 kPa (29.0 psig/43.8 psia) at 20 ºC (68 ºF). You seek confirmation that the gas mixture you describe is not subject to the HMR. Section 173.22 states it is the responsibility of the shipper to classify a hazardous material. However, based on the information you provided, this Office agrees that a phosphine/nitrogen mixture within a cylinder that has a calculated LC50 of 200,000 ppm and a pressure less than 200 kPa does not meet the definition of a Division 2.1 or Division 2.3 material under the HMR. Paragraphs (b)(2)(ii) and (iii) of § 173.29 state a packaging that is sufficiently cleaned of residue and purged of vapors to remove any potential hazard, or that is refilled with a material that is not subject to the HMR to the extent that any residue that remains in the packaging no longer poses any hazard, is not subject to the requirements of the HMR. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, T. Glenn FosterChief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division#

Page 2Dodd, Alice (PHMSA) From: INFOCNTR (PHMSA) Sent: Wednesday, September 25, 2019 10:46 AM To: Hazmat Interps Subject: FW: Request for Interpretation Attachments: Entegris Request for Interpretation 49 CFR Section 173.29 Empty Packaging.pdf Hello Alice and lkeya, Please see attached for letter of interpretation request. The requester sent in for a letter and Josh called to provide letters 15-0157 and 18-0011 which we deemed relevant. The requestor said that the 15 letter was close, however, he is still going through with this letter request since his material is a 2.3 and he wants that specifically addressed. Please contact our office with any questions. Thanks, Kathryn, HMIC From: Jim McManus [mailto:Jim.McManus@entegris.com] Sent: Tuesday, September 24, 2019 4:15 PM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Subject: Request for Interpretation Notes from Josh's call with Jim 9/25/19: -Has 2.3 material-toxic by inhalation -wants a letter specific to this hazard class -there is a complex calculation in this situation -a lot of people will mistakenly classify this material as hazmat even when its considered empty Dear Sir or Madame: Pursuant to 49 CFR §105.20, this letter is being submitted by e-mail to PHMSA to request an interpretation of a question I have related to §173.29 of the Hazardous Materials Regulations (HMR). Specifically, the question is related to a DOT specification cylinder package containing the residue of UN2199, phosphine and whether the package is subject to the requirements of the HMR after a cleaning and purging process. I greatly appreciates PHMSA's attention to this matter and look forward to a response that furthers my understanding of the Hazardous Materials Regulations. 1#

Page 3Should PHMSA require additional details to process this interpretation, please contact me using the information listed below. Regards, Jim Jim McManus Principal Engineer Dangerous Goods Safety Advisor (DGSA) M 203-482-1606 T 203-207-9307 E jim .mcmanus@entegris.com entegris.com 50 YEARS OF PURE ADVANTAGE 7 Commerce Drive Danbury, CT 06810 United States CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments. If you are not the intended recipient, you are hereby notified that any use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. 2#

Page 40;. Entegris Specialty Gas and Engineere d Materials 7 Commerce Drive Danbury, CT06810 800.766.2681 T oll-F ree 203.794.1100 Direct 203.792.8040 Facsimile www.entegris.com September 24, 2019 Standards and Rulemaking Division Pipeline and Hazardous Materials Safety Administration, Attn: PHH-10 U.S. Department of Transportation East Building 1200 New Jersey Avenue, SE Washington, DC 20590-0001 infocntr@dot.gov Re: Request for Interpretation Dear Sir or Madame: Pursuant to 49 CFR §105.20, this letter is being submitted by e-mail to PHMSA to request an interpretation of a question I have related to §173.29 of the Hazardous Materials Regulations (HMR). Specifically, the question is related to a DOT specification cylinder packagecontainingthe residue of UN2199, phosphine and whether the package is subject to the requirements of the HMR after a cl ea ni ng and purging process. Cylinder Cleaning and Purging Process A 50 liter DOT-3AA 2400 cylinder package contains the residue of UN 2199, phosphine. The cylinder package is cleaned of residues and purged of vapors using a vacuum pump and nitrogen purging to remove any potential hazard such that the cylinder package should not be subject to the requirements of the Hazardous Materials Regulations as it conforms with provisions (ii) and (iii) of §173.29(b)(2). After the cleaning and purging process, the remaining gas within the cylinder is analyzed and found to contain 100 parts-per-million by volume (ppmv) of phosphine and the remaining balance of gas in the cylinder is nitrogen. The pressure of the phosphine/nitrogen gas mixture contained in the cylinder is 103.4 kPa (15 psig) at 20 °C (68 °F). In order to determine if the cylinder contents pose any potential hazard, the toxicity of the phosphine/nitrogen gas mixture is determined using the method of calculation specified for gas mixtures in §173.11S(c)(2). §173.115(c)(2) specifies that the LC50 values for mixtures may be determined using the formula in §173.133(b)(1)(i) or CGA P-20 (I BR, see §171. 7). The formula given in CGA P-20 for determining the LC50 of a binary mixture is as follows: ppmLCso of toxiccomponent .x 1000 000 ppm of toxic component As the LCso for pure phosphine is 20 ppm, the LC50 for the 100 ppmv phosphine/nitrogen mixture described above is calculated as follows: LC50 phosphine/nitrogen mixture= 20 ppm/100 ppm x 1000 000 = 200,000ppm#

Page 5Classification of Cleaned and Purged Cylinder §173.116 assigns the four hazard zones for Division 2.3 materials depending on the LC50 of the gas. The criteria used to determine the hazard zone for a Division 2.3 material is shown in the table below: Hazard zone Inhalation toxicity A LC 50 less than or equal to 200 ppm. B LC50 greater than 200 ppm and less than or equal to 1000 ppm. C LC50 greater than 1000 ppm and less than or equal to 3000 ppm. D LC50 greater than 3000 ppm or less than or equal to 5000 ppm. For a gas to be considered Division 2.3 material, it must fall within one of the four hazard zones. A material with an inhalation toxicity > 5000 ppm would fall outside this criteria and would not be considered a Division 2.3 material. Therefore, I conclude the phosphine/nitrogen mixture is not classified as a hazardous material for the following reasons: ✓ The calculated LC50 (200,000 ppm) for the phosphine/nitrogen mixture does not fall within any of the hazard zone criteria and therefore the 100 ppm phosphine/nitrogen mixture would not be classified as a Division 2.3 material. ✓ Since the pressure of the phosphine/nitrogen mixture inside the cylinder is less than 200 kPa (29.0 psig/43.8 psia) at 20 °C (68 °F), it would not be classified as a Division 2.2 material. Question : Based on the information in the preceding discussion, does PHMSA agree with the following statement? Since the 100 ppmv phosphine/nitrogen mixture has a calculated LC50 of 200,000 ppm and the cylinder pressure is less than 200 kPa (29. 0 psig/43. 8 psia) at 20 °C (68 °F}, the gas mixture contained in the cylinder should not be subject to the Hazardous Materials Regulations. I greatly appreciates PH MSA's attention to this matter and look forward to a response that furthers my understanding of the Hazardous Materials Regulations. Should PHMSA require additional details to process this interpretation, please contact me using the information listed below. Sincerely, (\ d o,iw/ V 1)1_ ( U{ - James (Jim) V. McManus Principal Engineer Dangerous Goods Safety Advisor (DGSA) Entegris Inc. M 203-482-1606 0 203-207-9307#