Arizona Department of Public Safety — Hazardous Materials Safety Interpretation

Page 1U.S. Department 400 Seventh St., S.W of Transportation Washington, D.C. 20590 Research and Special Programs Administration FEB 6 2001 Mr. Steve Herman Ref. No. 99-0248 Hazardous Materials Coordinator Arizona Department of Public Safety 2102 West Encanto Boulevard Phoenix, Arizona 85005-6638 Dear Mr. Herman: This is in further response to your letter dated September 3, 1999, requesting clarification of the ; 173.315(k) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) equirements applicable to non-specification cargo tanks operating under the provisions o Specifically, you asked if the final rule adopted under HM-225A requires these cargo tanks to be equipped with an internal self-closing stop valve. The answer is yes. However, we have reconsidered our conclusion, in our October 20, 1999 letter to you, as to the date by which non-specification cargo tanks must be equipped with internal self-closing stop valves. Section 180.405(n) of the HMR requires non-specification cargo tanks conforming to § 173.315(k) to be equipped with a means of thermal activation for the internal self-closing stop valve by the date of its first scheduled leakage test after July 1, 1999. The thermal activation device must meet the requirements for thermal remote operators in § 178.337-8(a)(4). This requirement does not apply to a non-specification cargo tank authorized under § 173.315(k) that is not currently equipped with an internal self-closing stop valve. Although a non-specification cargo tank that does not have an internal self-closing stop valve need not be retrofitted with a thermal activation device at this time, it will be necessary to install such a device as part of the emergency discharge control system retrofit program required under $180.405(m). This section requires a non-specification cargo tank authorized under § 173.315(k) to be equipped with an emergency discharge control capability as specified in § 173.315(n) at the date of its first scheduled pressure test after July 1, 2001. Section 173.315(n) requires each cargo tank used to transport liquefied compressed gas to have an emergency discharge control capability. For each cargo tank operating in metered delivery service, as defined in § 171.8, with a capacity of 3,500 gallons or less, the emergency discharge control capability consists of an off- truck means to close the internal self-closing stop valve and shut off all motive and auxiliary power (see § 173.315(n)(3)). Thus, at the date of its first scheduled pressure test after July 1, 2001, each non-specification cargo tank operating under § 173.315(k) in metered delivery 990248#

Page 2service must be equipped with an internal self-closing stop valve and an off-truck means to close the valve and shut off all motive and auxiliary power. When the internal self-closing stop valve is installed, each non-specification cargo tank must also be equipped with a means of thermal activation for the internal self-closing stop valve in accordance with § 180.405(n). I hope this information is helpful. If you have further questions, please do not hesitate to contact this office. Sincerely, Director, Office of Hazardous Materials Standards#

Page 3ARIZONA DEPARTMENT OF PUBLIC SAFETY 2102 WEST ENCANTO BLVD. P. O. BOX 6638 PHOENIX, ARIZONA 85005-6638 (602) 223-2000 JANE DEE HULL GOVEHNON OE ALB IRECTO September 3, 1999 U.S. Department of Transportation Research & Special Programs Administration 3173.315 ATTENTION: Mr. Ed Mazzullo Office of Hazardous Materials Standards 400 Seventh Street S.W. Washington, DC 20590 99-0248 Dear Sirs: regarding the requirement for a internal self-closing stop valve on a nonspecification I am writing to clarify the intent of the recently adopted Docket HM-225A changes cargo tank operating under the provisions of 49 CFR 173.315(k). New wording in 173.315(k)(5) states such a tank must "....be) equipped...as specified for MC 331 cargo tanks. requirements of this subchapter," such a nonspecification tank would be subject to Further, since 173.315(k)(8) states "It must be operated in conformance with all other means to close the internal self-closing stop valve..." 173.315(n), specifically 173.315(n)(3) which states, ...must have an off-truck remote paragraph (k) of this section must have a thermal means of closure for each internal Finally, since 173.315(p) provides "...or nonspecification cargo tank authorized under self-closing stop valve as specified in Sec. 178.337-8(a)(4) of this subchapter," the tank is subject to 178.337-8(a)(4) which provides, " must be fitted with a primary discharge control system as defined in Sec. 178.337-1(g)," "...each liquid or vapor discharge outlet such a nonspecification tank would be subject to 178.337-1(g) which states, "Primary discharge control system means a primary shut-off installed at a product discharge outlet of a cargo tank consisting of an internal self-closing stop valve... tank operating under the provisions of 49 CFR 173.315(k) must be equipped with an In light of all of the above, is my understanding correct that a nonspecification cargo internal self-closing stop valve? Please do not hesitate to contact me at 602-223-2886 if my request for an interpretation is not clear. Sincerely Steve Hermann Hazardous Materials Coordinator#