Los Alamos National Laboratory — Hazardous Materials Safety Interpretation

Page 11200 New Jersey Avenue, SE vrue+h$on, D.C. 20590 U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration MAR 1 8 259 Ms. Lorelei Johnson Transportation Specialist Weapons Engineering Technology (WT-DO) High Explosives Engineering (WT-5) Los Alamos National Laboratory P.O. Box 1663, Mail Stop C932 Los Alamos, NM 87545 Reference No. 08-0049 Dear Ms. Johnson: This is in response to your January 22,2008 letter asking if a Class 1 (explosive) compatibility group letter must be displayed on an EXPLOSIVE placard when the material is transported by motor vehicle under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171- 180). You note that 5 172.522(b) requires the compatibility group letter for the Division 1. I, 1 -2, or 1.3 (explosives) placard, but 5 172.504(g) does not address transportation by motor vehicle. The answer is no. Section 172.504(g) requires the display of the compatibility group letter on placards or labels, if appropriate (see 5 172.4 1 l), for shipments of Class 1 material transported by aircraft or vessel only. If more than one compatibility group placard is required, 5 172.504(g) requires only one of these placards to be displayed provided this placard conforms with the precedence requirements prescribed in paragraphs (g)(l) through (g)(4) of that section. Although the HMR does not require the compatibility group letter for motor vehicle and railcar shipments of Class 1 material, please note that § 172.502(c) permits it to be displayed provided the placards otherwise conform to the requirements prescribed in 49 CFR Part 172, Subpart F (placarding). Section 172.401(a)(2) also permits a hazard warning label to be displayed provided the label represents the hazard class of the material in the package. I hope this satisfies your request. H'attie L. Mitchell Chic$ Regulatory Review and Reinvention Office of Hazardous Materials Standards#

Page 2I 1 NATIONAL Alamos LABORATORY EST.1943 - F'Bu'm Weapons Engineering Technology (WT-DO) High Explosives Engineering (WT-5) P.O. Box 1663, Mail Stop C932 Los Alarnos, New Mexico 87545 Date: January 22, 2008 505-667-6563lFax 505-665-0467 Rehr TO: VVT-5-08:0005 Mr. Edward Mauullo Director of the Office of Hazardous Materials Standards U.S. DOTP HMSA (PHH-10) 1200 New Jersey Avenue SE Building 2"d Floor Washington, DC 20596 Sir, I have a question concerning displaying the compatibility group letter on explosive placards. 172.522 (b) "The shall be replaced with the appropriate division number and, when required, appropriate compatibility group letter." My question is: Is the compatibility group letter required for highway transportation? 172.504 (g) does not address highway transportation. Thank you, Lorelei Johnson, WT-5, C932 Transportation Specialist c y : WT-5 File#