Weatherford International — Hazardous Materials Safety Interpretation

Page 1U.S. Department 1200 New Jersey Avenue SE of Transportation Washington. DC 20590 Pipeline and Hazardous Materials Safety Administration fEB 1 0 1012 Mr. Tim Redwine Weatherford International 495 Winscott Road Fort Worth, Texas 761256 Reference No.: 11-0311 Dear Mr. Redwine: This responds to your letter requesting clarification of Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to limited quantities of compressed gases. In your incoming letter, you describe an accumulator system that functions as part of a natural gas or oil drilling rig. You also include a picture of this accumulator system. You ask whether this accumulator system, as shown in the picture, is excepted from the HMR as specified in § 173.306(f). The answer is yes. In accordance with § 173.306(f)(1), provided the accumulator system is installed in either a motor vehicle, construction equipment, or assembled machinery and is designed and fabricated with a burst pressure of not less than five times their charged pressure at 70 oF., the accumulator system would not be subject to any other requirements of the HMR. As described in your incoming letter and shown in the accompanying picture, this accumulator system meets the requirements specified in § 173.306(f)(1) and is excepted from the HMR. I trust 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 2September I, 2011 'Bene dicJ'9 r13. 3D(o (j'fl.) ~ til") d~,.-s 11-03// Mr. Charles E. Betts Director, Office of Hazardous Materi als Standards U.S. DOT/PHMSA (PHH- I O) 1200 New Jersey Avenue, SE East Buildi ng, 2nd Floor Washington, DC 20590 Dear Mr. Betts: This letter is written requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Pa rts 171- 180) applicable to limited quantities of com pressed gases. Will the accumulator system pictured below be excepted from regulat ion under § 173 .306(f) ( 1). This type of equipment is to be transported to an oil or natural gas site drilling rig and is used to " shut in" a well bore . Each cylinder has a burst pressure 5 times greater than t he charged pressure @ 70 degrees. The five accumulators pictured are plumbed into a manifold system with each cylinder pre-charged to 1000 psig. Sincerely, Tim Redwine US DOT Compliance Coordinator Weatherford I nternational 495 Winscott Rd Fort Worth, Texas 761256 Telephone: 817.249.7861 Email: tim.redwine@weatherford.com#