Guidanceguidance
10-0174
Integrity Inspection Services — Hazardous Materials Safety Interpretation
Current as of source date Government source
RegulusPipeline researchRegulusPipeline research10-0174
Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration SEP 3 2010 1200 New Jersey Ave, SE Washington, D.C. 20590 ~r.JanaesJagernann Integrity Inspection Services 21422 Provincial Boulevard Katy, TX 77450 Ref. No. 10-0174 Dear ~r. Jagernann: This responds to your August 12,2010 enaail regarding the transportation ofradioactive· naaterial under the Hazardous ~aterials Regulations (H~R; 49 CFR Parts 171-180). Specifically, you request clarification ofthe naethod of calculation used to deternaine the level of contanaination on the external surfaces ofa package in accordance with § 173.443 ofthe HMR. Your question is paraphrased and answered as follows: For instances when the wipe efficiency is assunaed to be 0.10, ifthe instrunaent used to naeasure radioactivity provides a reading in counts per nainute (cpna), do I need to include a factor to convert cpna to disintegrations per nainute (dpna) or does the assunaed 0.10 wipe efficiency incorporate a conversion frona cpna to dpna? In addition to the assunaed 0.10 wipe efficiency, an instrunaent efficiency factor is needed to calculate the contanaination activity on the wiping naaterial. The wipe efficiency factor does not account for the effectiveness ofthe instrunaent in naeasuring radioactivity. The instrunaent efficiency factor is a function ofthe efficiency ofthe specific instrunaent in naeasuring the radioactivity on the wiping naaterial. This instrunaent efficiency factor naay be provided on the instrunaent, obtained through the naanufacturer or supplier ofthe instrunaent, or deternained by using reference standards ofknown radioactivity. Therefore, in your case, both a wipe efficiency factor and an instrunaent efficiency factor are needed to calculate the level of contanaination in dpna. I hope this infornaation is helpful. Ifyou have further questions, please contact this office. Sincerely, <BWt~~ Ben Supko Acting Chief, Standards Developnaent Office ofHazardous Materials Standards#
Page 2Drakeford, Carolyn (PHMSA) From: INFOCNTR (PHMSA) KANl Sent: Friday, August 13, 2010 9:00 AM 10- Oli'f To: Drakeford, Carolyn (PHMSA) Cc: DerKinderen, Dirk (PHMSA) Subject: FW: Hazmat Information Center Feedback: General Information, Regulations, and Definitions (Sections 171.1 – 171.26) -----Original Message----From: PHMSA-Feedback [mailto:PHMSA-Feedback] Sent: Thursday, August 12, 2010 1:05 PM To: PHMSA HM InfoCenter; PHMSA Webmaster Subject: Hazmat Information Center Feedback: General Information, Regulations, and Definitions (Sections 171.1 – 171.26) I would like to obtain clarification for the calculation of NORM loose surface contamination for DOT purposes is correct. Per the regulations: Removable (loose) contamination levels shall be established by w1p1ng an area of 300cm2 of the surface concerned with an absorbent material, using moderate pressure, and measuring the activity on the wiping material. Sufficient measurements must be taken in the most appropriate locations to yield a representative assessment of the non-fixed contamination levels. [49CFR173.443(a) (1)] The amount of radioactivity measured on any single wiping material, divided by the surface area wiped and the efficiency of the wipe procedure (the fraction of removable contamination transferred from the surface to the absorbent material), may not exceed 22 dpm/cm2 alpha or 220 dpm/cm2 beta/gamma. For this purpose the actual wipe efficiency may be assumed to be 0.10. [49CFR173 .443 (a)(1) ] If using the above regulations, the loose surface calculation would be: cpm/300/0.1/ = dpm/cm2 where: • cpm = meter reading • 300 = wipe area cm2 • 0.1 wipe efficiency My question is, do I also need to input a factor for converting cpm to dpm due to the fact that the field survey instrument used to count the smear reads out in units of cpm or does the above wipe efficiency assumption include that conversion? Thank you for your help in this matter. ~~~~~li~~~~ Jageman~ Email: james.jagemann@yahoo.com Phone: 713-885-2745 1:-k Jr-{f1 ~ ~p e.J ~t.h Su VILL':;:. 7l'lz '- P('~"' '''c-~ t 6l,J. ~ r {efti5 77150 1#
This material provides agency context. It does not replace binding regulatory text, and its legal effect depends on the underlying authority and facts.