# Swagelok Northern California — Hazardous Materials Safety Interpretation - **operation:** document - **citation:** 16-0187 - **title:** Swagelok Northern California — Hazardous Materials Safety Interpretation - **source type:** guidance - **agency:** Pipeline and Hazardous Materials Safety Administration - **status:** guidance - **official:** true - **published on:** 2017-04-19 - **effective on:** Not available - **summary:** 16-0187 response to Swagelok Northern California concerning 173.40. - **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-16-0187.json - **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-16-0187.md - **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-16-0187 - **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/2017/160187.pdf **body:** <<>> of Transportation U.S. Department 1200 New Jersey Avenue, SE Materials Safety Pipeline and Hazardous Washington, DC 20590 Administration APR 1 9 2017 Mr. Cameron Banks Account Manager Swagelok Northern California 3393 West Warren Avenue Fremont, CA 94538 Reference No. 16-0187 Dear Mr. Banks: This letter is in response to your November 14, 2016, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to cylinder valve integrity. In your email, you cite the valve pressure capability requirements under § 173.40(c)(1) as an example of valve integrity for cylinders used in toxic-by-inhalation service. Specifically, you ask whether the valve of a Department of Transportation (DOT) Specification 4B cylinder must meet either the minimum service pressure or test pressure requirements of the HMR. You are correct in your citation that for cylinders in toxic-by-inhalation service "each plug or valve must...be capable of withstanding the test pressure of the cylinder without damage or leakage" as stated in § 173.40(c)(1). The HMR do not include a similar requirement (such as valve pressure ratings) for cylinders not in toxic-by-inhalation service; however, there are valve requirements provided in the general requirements for cylinders (see § 173.301). For DOT Specification 4B cylinders, § 178.50(h) specifies the thread requirements, including engaged threads and shear strength. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, THere ter. T. Glenn Foster Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division <<>> stevens 178.50 (a) Dodd, Alice (PHMSA) cylinders 16-0187 From: Sent: INFOCNTR (PHMSA) To: Monday, November 14, 2016 1:50 PM Subject: Hazmat Interps FW: letter of clarification regarding valve ratings for 49 CFR 178.50(a) Spec 4B steel Attachments: cylinders? 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders.pdf; CFR 173.40 c.JPG Follow Up Flag: Follow up Flag Status: Flagged Hi Shante/Alice, Please submit this as a letter of interpretation. Mr. Banks spoke with Eamonn. Please let me know if you have any questions. Thanks, Jordan From: Banks, Cameron J. [mailto: cbanks@swagelok.com] Sent: Monday, November 14, 2016 12:41 PM To: PHMSA HM InfoCenter Subject: letter of clarification regarding valve ratings for 49 CFR 178.50(a) Spec 4B steel cylinders? DOT, CFR 178.50 (a) clearly states that a DOT 4B cylinder has to have a service pressure of "at least 150 but not over 500 psig". It seems common sense that any valves attached to such a cylinder would also require the same minimum rating ("at least 150 psig"), but I've been unable to find that requirement stated explicitly anywhere. Can you confirm that any attached valves need to meet the 150 psig minimum service pressure? I do see that for 6.1 Hazard Zone A materials (toxics, basically), CFR 173.40 (c) (1) states that "each plug or valve...be capable of withstanding the test pressure of the cylinder without damage or leakage." This reference to cylinder test pressure (as opposed to service pressure) seems to set a relatively high standard for the attached valves, suggesting that they would have to withstand 3x or more of the actual cylinder service pressure. Is that correct, or was the intent to specify service pressure in this case? Thank you, Cameron Banks Cameron Banks Account Manager Swagelok Northern California Swagelok 510.933.2500 office 3393 West Warren Avenue 510.933.6239 desk Fremont, CA 94538 408-806-9820 cell 1 <<>> Check out our refreshed website. New Look, New URL http://northerncal.swagelok.com/ Welcome to Swagelok Swagel Northern California Our Vision is to be our customer's favorite story. Please click here and let us know how we are doing 2 <<>> 11/7/2016 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders. | US Law | LIl / Legal Information Institute (https://www.cornell.edu)Cornell University Law School (http://www.lawschool.cornell.edu/)Search Cornell (https://www.cornell.edu/search/) (/cfr/text/49/part-178/subpart-C) › Section 178.50 CFR (/cr/text) › Title 49(/cfr/text/49) › Subtitle B (/cr/text/49/subtitle-B) › Chapter I (/cr/text/49/chapter-l) › Part 178 (/cfr/text/49/part-178) › Subpart C 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders. Rulemaking (/cfr/text/49/178.507qt-cfr_tabs=2#qt-cfr_tabs) eCFR (/cfr/text/49/178.50?qt-cfr_tabs=0#qt-cfr_tabs) Authorities (U.S. Code) (/cfr/text/49/178.50?qt-cfr_tabs=1#qt-cfr_tabs) Beta! (/ii/ecfr_beta) The text on the CFR tab represents the unofficial eCFR text at ecfr.gov. What Cites Me (/cfr/text/49/178.502qt-cfr_tabs=3#gt-cfr_tabs) $ 178.50 Specification 4B welded or brazed steel cylinders. • water capacity (nominal) not over 1,000 pounds and a service pressure of at least 150 but not over 500 psig. Cylinders closed in by spinning process are not (a) Type, size, and service pressure. A DOT 4B is a welded or brazed steel cylinder with longitudinal seams that are forged lap-welded or brazed and with authorized. (b) Steel. Open-hearth, electric or basic oxygen process steel of uniform quality must be used. Content percent may not exceed the following: Carbon, 0.25; phosphorus, 0.045; sulphur, 0.050. (c) Identification of material. Material must be identified by any suitable method except that plates and billets for hotdrawn cylinders must be marked with the heat number. (d) Manufacture. Cylinders must be manufactured (/definitions/index.php? using equipment and processes adequate to ensure that each cylinder produced conforms to the requirements of this subpart. No defect width=840&height=800&iframe=true&def_id=8bdcb6d41890e7cd2bb14f08a0c28946&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) width=840&height=800&iframe=true&def_id=51f8be37857e06aa9d5a242e6c8b1cd0&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) (/definitions/index.php? is permitted that is likely to weaken the finished cylinder appreciably. A reasonably smooth and uniform surface finish is required. Exposed bottom welds on width=840&height=800&iframe=true&def_id=0647def6117826997d6402a64662fd46&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpait:C:178.50) cylinders over 18 inches long must be protected by footings. Welding procedures and operators (/definitions/index.php? must be qualified in accordance with CGA Pamphlet C-3 (IBR, see § 171.7 (https://www.law.cornell.edu/cfr/text/49/171.7) of this subchapter). Seams must be made as follows: width=840&height=800&iframe=true&def_id=2568b33a83ea5eed613016527d1d0bb9&term_occur=2&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50). (1) Welded or brazed circumferential seams. Heads attached by brazing must have a driving fit with the shell (/definitions/index.php? width=840&height=800&iframe=true&def_id=76ea16926e9f1de9821c42734c4a8cdb&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) is crimped, swedged, or curled over the skirt or flange (/definitions/index.php? width=840&height=800&iframe=true&def_id=2568b33a83ea5eed613016527d1dObb9&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) unless the shell (/definitions/index.php? of the head, and be thoroughly brazed until complete penetration by the brazing material of the brazed joint is secured. Depth of brazing from end of shell width=840&height=800&iframe=true&def_id=2568b33a83ea5eed613016527d1d0bb9&term_occur=3&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) (/definitions/index.php? width=840&height=800&iframe=true&def_id=2568b33a83a5eed613016527d1 dObb9&term_occur=4&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) must be at least four times the thickness of shell (/definitions/index.php? metal. (2) Longitudinal seams in shells. Longitudinal seams must be forged lap welded, by copper brazing, by copper alloy brazing, or by silver alloy brazing. melting point of the silver alloy brazing material must be in excess of 1000 °F. When brazed, the plate edge must be lapped at least eight times the Copper alloy composition must be: Copper, 95 percent minimum; Silicon, 1.5 percent to 3.85 percent; Manganese, 0.25 percent to 1.10 percent. The thickness of plate, laps being held in position, substantially metal to metal, by riveting or electric spot-welding; brazing must be done by using a suitable flux and by placing brazing material on one side of seam and applying heat until this material shows uniformly along the seam of the other side. (e) Welding or brazing. Only the attachment of neckrings, footrings, handles, bosses, pads, and valve protection rings to the tops and bottoms of cylinders by welding or brazing is authorized. Such attachments and the portion of the container to which they are attached must be made of weldable steel, the carbon content of which may not exceed 0.25 percent except in the case of 4130X steel which may be used with proper welding procedure. width=840&height=800&iframe=true&def id=9d631188119ca31df2c14ed1d1260aaf&term occur=1&term_ src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) (f) Wall thickness. The wall thickness (/definitions/index.php? of the cylinder must comply with the following requirements: (1) For cylinders with outside diameters over 6 inches the minimum wall thickness (/definitions/index.php? width=840&height=800&iframe=true&def_id=9d631188119ca31df2c14ed1d1260aaf&term_occur=2&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) width=840&height=800&iframe=true&def_id=9d631188119c31d/2c14ed1d1260aaf&term_occur=3&term src=Title:49:Subtitle:B:Chapter:I:Part:178:Subpart:C:178.50) must be 0.090 inch. In any case, the minimum wall thickness (/definitions/index.php? width=840&height=800&iframe=true&def_id=fad759af2b6a4c90ae53eda946b42bcb&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) must be such that calculated wall stress at minimum test pressure (/definitions/index.php? (paragraph (i)(4) of this section) may not exceed the following values: (i) 24,000 psi for cylinders without longitudinal seam. (ii) 22,800 psig for cylinders having copper brazed or silver alloy brazed longitudinal seam. https://www.law.cornell.edu/cfr/text/49/178.50 1/4 <<>> 11/7/2016 (iii) 18,000 psi for cylinders having forged lapped welded longitudinal seam. 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders. | US Law | LII / Legal Information Institute (2) Calculation must be made by the formula: S = [P(1.3D 2 0.4d 2)) / (D2 - d 3) Where: P = minimum test pressure prescribed for water jacket test or 450 psig whichever is the greater, S = wall stress in psi; D = outside diameter in inches; d = inside diameter in inches. (g) Heat treatment. Cylinder body and heads, formed by drawing or pressing, must be uniformiy and properly heat treated prior to tests. (h) Opening in cylinders. Openings in cylinders must conform to the following: welding or by threads. Fitting, boss, or pad must be of steel suitable for the method of attachment employed, and which need not be identified or verified as (1) Each opening in linders, except those for safety devices, must be provided with a fitting, boss, or pad, securely attached to cylinder by brazing or by to analysis except that if attachment is by welding, carbon content may not exceed 0.25 percent. If threads are used, they must comply with the following: (1) Threads must be clean cut, even without checks, and tapped to gauge. (ii) Taper threads to be of length not less than as specified for American Standard taper pipe threads. (/definitions/index.php? (iii) Straight threads, having at least 4 engaged threads, to have tight fit and calculated shear strength at least 10 times the test pressure width=840&height=800&iframe=true&def_id=fad759af2b6a4c90ae53eda946b42bcb&term_occur=2&term_src=Title:49:Subtitle:B:Chapter:1:Part:178:Subpart:C:178.50) of the cylinder; gaskets required, adequate to prevent leakage. (iv) A brass fitting may be brazed to the steel boss or flange (/definitions/index.php? width=840&height=800&iframe=true&def_id=76ea16926e9f1de9821c42734c4a8cdb&term_occur=2&term src=Title:49:Subtitle:B:Chapter:|:Part:178:Subpart:C:178.50) on cylinders used as component parts of hand fire extinguishers. (2) The closure of a fitting, boss, or pad must be adequate to prevent leakage. (i) Hydrostatic test. Cylinders must withstand a hydrostatic test as follows: (1) The test must be by water-jacket, or other suitable method, operated so as to obtain accurate data. The pressure gauge must permit reading to an accuracy of 1 percent. The expansion gauge must permit reading of total expansion (/definitions/index.php? width=840&height=800&iframe=true&def_id=9ac735b4a0448d725d94bb514d8fccf4&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) to an accuracy either of 1 percent or 0.1 cubic centimeter. (2) Pressure must be maintained for at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat- width=840&height=800&iframe=true&def_id=fad759af2b6a4c90ae53eda946b42bcb&term_occur=4&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50). treatment and previous to the official test may not exceed 90 percent of the test pressure (/definitions/index.php? If, due to failure of the test apparatus, the test pressure (/definitions/index.php? width=840&height=800&iframe=true&def_id=fad759af2b6a4c90ae53eda946b42bcb&term_occur=3&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is the lower. (3) Permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure (/definitions/index.php? width=840&height=800&iframe=true&def_id=fad759af2b6a4c90ae53eda946b42bcb&term_occur=5&term_src=Title:49:Subtitle:B:Chapter:l:Part:178: Subpart:C:178.50). (4) Cylinders must be tested as follows: (i) At least one cylinder selected at random out of each lot of 200 or less must be tested as outlined in paragraphs (i)(1), (i)(2), and (i)(3) of this section to at least two times service pressure. (ii) All cylinders not tested as outlined in paragraph (i)(4)(i) of this section must be examined under pressure of at least two times service pressure and width=840&height=800&iframe=true&def_id=51f8be37857e06aa9d5a242e6c8b1cd0&term occur=2&term_ src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50). show no defect (/definitions/index.php? the cylinder between wedge shaped knife edges having a 60° included angle, rounded to 1/2-inch radius. The longitudinal axis of the cylinder must be at a () Flattening test. After the hydrostatic test, a flattening test must be performed on one clinder taken at random out or each lot of 200 or less, by placing 90-degree angle to knife edges during the test. For lots of 30 or less, flattening tests are authorized to be made on a ring at least 8 inches long cut from each cylinder and subjected to same heat treatment as the finished cylinder. (k) Physical test. A physical test must be conducted to determine yield strength, tensile strength, elongation, and reduction of area of material as follows: (1) The test is required on 2 specimens cut from 1 cylinder, or part thereof heat-treated as required, taken at random out of each lot of 200 or less. For lots finished cylinder. of 30 or less, physical tests are authorized to be made on a ring at least 8 inches long cut from each cylinder and subjected to same heat treatment as the (2) Specimens must conform to the following: least 24 times the thickness with a width not over 6 times the thickness is authorized when a cylinder wall is not over 3/16 inch thick. (i) A gauge length of 8 inches with a width of not over 1 1/2 inches, a gauge length of 2 inches with a width of not over 1 1/2 inches, or a gauge length at (ii) The specimen, exclusive of grip ends, may not be flattened. Grip ends may be flattened to within one inch of each end of the reduced section. (iii) When size of cylinder does not permit securing straight specimens, the specimens may be taken in any location or direction and may be straightened of physical tests detailed information in regard to such specimens. or flattened cold, by pressure only, not by blows. When specimens are so taken and prepared, the inspector's report must show in connection with record https://www.law.cornell.edu/cfr/text/49/178.50 ... .. 2/4 <<>> 11/7/2016 (IV) Meaung or a specimen or any purpose is not autorizea. 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders. | US Law | LIl / Legal Information Institute (3) The yield strength in tension must be the stress corresponding to a permanent strain of 0.2 percent of the gauge length. The following conditions apply: 171.7 (https://www.law.cornell.edu/cfr/text/49/171.7) of this subchapter). (i) The yield strength must be determined by either the "offset" method or the "extension under load" method as prescribed in ASTM E 8 (IBR, see § (ii) In using the "extension under load" method, the total strain (or "extension under load") corresponding to the stress at which the 0.2 percent permanent strain occurs may be determined with sufficient accuracy by calculating the elastic extension of the gauge length under appropriate load and controversy, the entire stress-strain diagram must be plotted and the yield strength determined from the 0.2 percent offset. adding thereto 0.2 percent of the gauge length. Elastic extension calculations must be based on an elastic modulus of 30,000,000. In the event of (iii) For the purpose of strain measurement, the initial strain must be set while the specimen is under a stress of 12,000 psi, and strain indicator reading must be set at the calculated corresponding strain. (iv) Cross-head speed of the testing machine may not exceed 1/8 inch per minute during yield strength determination. (I) Acceptable results for physical and flattening tests. Either of the following is an acceptable result: (1) An elongation of at least 40 percent for a 2-inch gauge length or at least 20 percent in other cases and yield strength not over 73 percent of tensile strength. In this instance, a flattening test is not required. width=840&height=800&iframe=true&def_id=9631188119a31 df2c14ed1d1260aaf&term occur=4&term src=Title:49: Subtitle:B: Chapter:I:Part:178:Subpart:C:178.50). (2) When cylinders are constructed of lap welded pipe, flattening test is required, without cracking, to 6 times the wall thickness (/definitions/index.php? another from the same end of pipe may be tested. In such case, the rings (crop ends) cut from each end of pipe, must be tested with the weld 45° or less from the point of greatest stress. If a ring fails, width=840&height=800&iframe=true&def_id=e59f069188b967310d2a0dbb0949ddc3&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:I:Part:178:Subpart:C:178.50). (m) Rejected cylinders. Reheat treatment is authorized for rejected cylinder (/definitions/index.php? width=840&height=800&iframe=true&def id=dbec91207d619b4c33a6286c57f9aa&term occur=1&term_src=Title:49: Subtitle:B:Chapter:I:Part:178:Subpart:C:178.50) Subsequent thereto, cylinders must pass all prescribed tests to be acceptable. Repair (/definitions/index.php? of brazed seams by brazing and welded seams by welding is authorized. (n) Markings. Markings (/definitions/index.php? must be stamped plainly and permanently in any of the following locations on the cylinder: width=840&height=800&iframe=true&def_id=0b38c26decbe8619dfb323ecb5fc2483&term_occur=1&term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) (1) On shoulders and top heads when they are not less than 0.087-inch thick. (2) On side wall adjacent to top head for side walls which are not less than 0.090 inch thick. width=840&height=800&iframe=true&def_id=2568b33a83ea5eed613016527d1dObb9&term_occur=58term_src=Title:49:Subtitle:B:Chapter:l:Part:178:Subpart:C:178.50) (3) On a cylindrical portion of the shell (/definitions/index.php? which extends beyond the recessed bottom of the cylinder, constituting an integral and non-pressure part of the cylinder. six retest dates; the plate must be at least 1/16-inch thick and must be attached by welding, or by brazing. The brazing rod must melt at a temperature of (4) On a metal plate attached to the top of the cylinder or permanent part thereof; sufficient space must be left on the plate to provide for stamping at least 1100 °F. Welding or brazing must be along all the edges of the plate. (5) On the neck, neckring, valve boss, valve protection sleeve, or similar part permanently attached to the top of the cylinder. (6) On the footring permanently attached to the cylinder, provided the water capacity of the cylinder does not exceed 25 pounds. [Amdt. 178-114, 61 FR 25942 (http://frwebgate.access.gpo.gov/cgi-bin/getpage.cgi?dbname=(1996)_register&position=all&page=25942), May 23, 1996, as 45385 (http://frwebgate.access.gpo.gov/cgi-bin/getpage.cgi?dbname=(2001)_register&position=all&page=45385), 45388, Aug. 28, 2001; 67 FR 51653 amended at 62 FR 51561 (http://frwebgate.access.gpo.gov/cgi-bin/getpage.cgi?dbname=(1997)_register&position=all&page=51561), Oct. 1, 1997; 66 FR (http://frwebgate.access.gpo.gov/cgi-bin/getpage.cgi?dbname=(2003)_register&position=all&page=75748), Dec. 31, 2003] (http://frwebgate.access.gpo.gov/cgi-bin/getpage.cgi?dbname=(2002)_register&position=all&page=51653), Aug. 8, 2002; 68 FR 75748 CFR Toolbox Lil on your phone: App Store Download on the Law about... Articles from Wex (/wex/wex articles) (https://itunes.apple.com/us/app/lawlibe/id403807492) Table of Popular Names (/topn) View eCFR (http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&tp|=/ecfrbrowse/Title49/49cfr178_main_02.tpl) Parallel Table of Authorities (/ptoa) Find a Lawyer SPONSORED LISTINGS -ARE Madel Momma Christina Chen (https://lawyers.law.cornell.edu/lawyer/christina-chen-1502985) https://www.law.cornell.edu/cfr/text/49/178.50 wers.law.cornell.edu/lawver/christina- 3/4 <<>> 11/7/2016 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders. | US Law | LIl / Legal Information Institute San Francisco, CA Bankruptcy (415) 984-9680 (tel:4159849680) website email profile James G. Schwartz (https://lawyers.law.cornell.edu/lawyer/james-g-schwartz-189349) ers.law.cornell.edu/lawyer/james- (925) 463-1073 (tel:9254631073) Pleasanton, CA Business Law, Civil Rights, Collections, Intellectual Property, Probate, Real Estate Law website email profile James Thomas Reilly (https://lawyers.law.cornell.edu/lawyer/james-thomas-reilly-29662) rers.law.cornell.edu/lawyer/james- Pleasanton, CA Criminal Law, DUI & DWI, Domestic Violence, White Collar Crime, Juvenile Law, Traffic Tickets (925) 218-4730 (tel:9252184730) website email profile Katya Mezek (https://lawyers.law.cornell.edu/lawyer/katya-mezek-1516240) rers.law.cornell.edu/lawyer/katya- San Jose, CA Business Law (408) 441-7500 (tel:4084417500) website email profile Tanya P. Tambling (https://lawyers.law.cornell.edu/lawyer/tanya-p-tambling-1492197) rers.law.cornell.edu/lawyer/tanya- (510) 663-9240 (tel:5106639240) Oakland, CA Civil Rights, Employment Law, Personal Injury wposte email profile About LIl (/i/about/about_lii) (lil/about/contact_us) Contact us Advertise here (/li/help_out/sponsor) Help (/li/help) Terms of use (/lii/terms/documentation) https://www.law.cornell.edu/cfr/text/49/178.50 4/4 <<>> following: subchapter). (a) Authorized cylinders, MEGCs is prohibited for Hazard Zone A materials. provided so that the cylinder will not be liquid full at 55 °C (131 °F). Zone A material or a Division 6.1 Hazard Zone A material. requirements in this section are applicable to cylinders used for that material. Beta! The text on the CFR tab represents the unofficial CFR text at ecfr.gov. In the valvo haru or the rulindor to nravant Ince of matorial thrunh or nact the narkinn (4) For UN seamless cylinders used for Hazard Zone A materials, the maximum water capacity is 85 L. When this section is referenced for a Hazard Zone A or B hazardous material elsewhere in this subchapter, the § 173.40 General packaging requirements for toxic materials packaged in cylinders. either a taper thread or other means which meets the requirements of ISO 10692-2: (IBR, see § 171.7 of this (c) Closures. Each cylinder containing a Hazard Zone A material must be closed with a plug or valve conforming to the Zone A and Hazard Zone B materials may not exceed the service pressure of the cylinder. Sufficient outage must be (b) Outage and pressure requirements. For DOT specification cylinders, the pressure at 55 °C (131 °F) of Hazard (2) Each valve must be of the packless type with non-perforated diaphragm, except that, for corrosive materials, a of withstanding the test pressure of the pressure receptacle and be connected directly to the pressure receptacle by (2) The use of a specification 3AL cylinder made of aluminum alloy 6351-T6 is prohibited for a Division 2.3 Hazard (1) A cylinder must conform to a DOT specification or a UN standard prescribed in subpart C of part 178 of this valve may be of the packed type with an assembly made gas-tight by means of a seal cap with gasketed joint attached the test pressure of the cylinder without damage or leakage. For UN pressure receptacles, each valve must be capable (1) Each plug or valve must have a taper-threaded connection directly to the cylinder and be capable of withstanding (3) A UN composite cylinder certified to ISO-11119-3 is not authorized for a Division 2.3 Hazard Zone A or B material. subchapter, except that acetylene cylinders and non-refillable cylinders are not authorized. The use of UN tubes and - **truncated:** false - **body characters:** 25931