International Paper — Hazardous Materials Safety Interpretation

Page 1U.5. Department 400 Seventh St., S.W. Research and of Transportation Washington, D.C. 20590 special Program: Administratior JAN - 2 2001 Mr. Richard Ruebush Ref. No. 00-0191 International Paper P.O. Box 4687 Spartanburg, SC 29304-5687 Dear Mr. Ruebush: This is in response to your letter dated July 10, 2000, regarding construction of "UNSM2" paper bags of three plies and four plies authorized in § 178.521(b)(2) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). You state the multi-wall bags are sometimes constructed either with plastic film plies or plastic film plies laminated to paper plies with adhesives, either with all over adhesive coverage or stripes of adhesive. Your questions are paraphrased and answered as follows: Q1. Does the statement in § 178.521(b)(2) in reference to the number of plies only mean paper plies, or does it also include plastic film plies which may be used in combination with paper plies? Al. The " UNSM2" multi-wall bag must be made of suitable kraft paper or an equivalent paper with at least three plies. To prevent the entry of moisture, a plastic film ply may be used as a waterproof ply or water-resistant barrier in combination with paper plies as prescribed § 178.521(b)(2). 02. Is the plastic film ply considered a separate ply if it is laminated or bonded in some way to a paper ply, or is it only considered a separate ply if it is free and not bonded to a paper ply. A2. A plastic film ply bonded or laminated to the inner surface of a three ply bag as a waterproof ply or barrier would be considered a separate ply. 178.52) 000191#

Page 2Q3. Is a bag constructed of a plastic film inner ply laminated to a ply of kraft paper having an outer ply of water-resistant kraft paper considered a three ply "UNSM2" bag. A3. Yes, provided the bag complies with all other requirements of § 178.521 and meets the testing requirements of Subpart M of Part 178. I hope this satisfies your inquiry. If we can be of further assistance, please contact us. Sincerely, She Ailfis Delmer F. Billings Chief, Standards Development Office of Hazardous Materials Standards#

Page 3INTERNATIONAL PAPER Engrum $178.521 CUSTOMER RESOURCE CENTER P.O. BOX 5687 PHONE: 864-596-7140 SPARTANBURG, SC 29304-5687 980-0191 FAX: 864-596-7175 July 10, 2000 U.S. Department of Transportation 400 Seventh Street, S.W. Rescarch and Special Programs Administration Washington, D.C. 20590-0001 Office of Hazardous Materials Standards DHM-10: I have some questions about SM2 paper bags as mentioned in 49 CFR 178.521(b)(2). My questions are in reference to the statements about bags of three plies and bags of four plies or more. Multiwall bags are sometimes constructed either with plastic film plies between paper plies or plastic film plies laminated to paper plies with adhesives, either with all over adhesive coverage or stripes of adhesive. Does the statement about the number of plies only mean paper plies or does it also include plastic film plies which may be in combination with the paper plies? 2. Is the plastic film ply considered a separate ply if it is laminated or bonded in some way to a paper ply or is it only considered a separate ply if it is free and not bonded to a paper ply? I would be grateful if you can provide some clarification on these issues for me. Please contact me if you need more information at 864-596-7159 or at the address on the letterhead. Regards, Richard Ruebush Richard Ruebush DOT Packaging Coordinator#