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PERS Regulatory Alert

Marking of Cargo Tanks Transporting Petroleum Distillate Fuels

(Table Added to §172.336 / Change to Previous Interpretations)



Date:  March 20, 2015

Subject:  §172.336 Identification numbers: special provisions

Posted By:  Rick Heylmun / PERS 


Summary: PHMSA published a new proposed rulemaking (NPRM) HM-219 on Thursday May 24, 2012 that proposed several changes and clarification to the HMR. The NPRM proposed that all references to “gasohol” would be removed and that a table would be added to §172.336 “that will more clearly indicate the identification number marking requirements for compartmented cargo tanks, tank cars, or cargo tanks containing these fuels”.  The NPRM did not state that changes were being made to the marking requirements but that the table was for the purpose of clarity.


On Thursday, March 7, 2013 Final Rule HM-219 was published and made effective May 6, 2013. The proposed table was added to §172.336.  I contacted the PHMSA information office in order to receive clarification of the effect that the new language of the table would have on the requirement and on previously issued interpretations. I was told that there was no change to the requirement and that the final rule did not change the previously published interpretations of §172.336.  I asked if, under the final rule, a cargo tank motor vehicle (CTMV) may continue to be marked for gasoline (1203) when transporting diesel fuel and having no gasoline on board as had been previously authorized. I was told yes. I stated that if it was not intended to make a change to the requirement that the new language was very confusing.


Recently, I contacted the PHMSA information office again in order to further discuss this regulation and I was informed that PHMSA had written a new interpretation of this section that substantially changes previous interpretations and makes a different requirement for the marking of cargo tanks transporting petroleum distillate fuels. The new reference number for the interpretation is 14-0178. The interpretation is posted below.


In summary, the change to the regulation is a considerable burden to the petroleum industry, particularly to the operators of CTMV's transporting petroleum distillate fuels.  Companies transporting petroleum distillate fuels may not be aware of the new rule change or be prepared to comply.  It is common practice for CTMV’s to be marked for gasoline (1203) when transporting only diesel fuel or other petroleum distillate fuels, with no gasoline on board.  A large number of vehicles will be subject to penalties if strict attention to this new rule is not observed. 


The final rule identifies that comments were made to the NPRM, but there were no comments made by affected parties to the “clarification” of §172.336.  I doubt this would have been the case if the NPRM had clearly stated that this section was being changed by this NPRM, rather than just indicating that the rule is being clarified by inserting a table.


Should you have questions or wish to discuss this issue, please contact PERS at 1-800-728-2482 or contact us through our site.


Best Regards,

Rick Heylmun, PERS






PHMSA Response Letter


June 26, 2015


First Sergeant Dean DillSouth

Carolina State Transport Police

10311 Wilson Boulevard

Blythewood, SC 29016


Reference No. 14-0178


Dear First Sergeant Dill:


This is in response to your recent e-mail and telephone conversations with a member of my staff requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the marking requirements for multi-compartment cargo tanks containing petroleum distillate fuels. You state you encountered a four-compartment cargo tank with all of its compartments filled with " NA 1993, Diesel fuel, 3, PG III" that was marked with the identification number for "UN 1203, Gasoline, 3, PG II." You ask if this marking is permitted.


The answer is no. The regulatory text in former § 172.336(c)(6), currently listed as the fifth item in the table under § 172.336(c) (see 78 FR 65454), permits a compartmented cargo tank loaded with more than one liquid petroleum distillate fuel to display only the identification number of the fuel with the lowest flash point being transported. In your example, all of the compartments in the cargo tank were loaded with only one petroleum distillate fuel. Therefore, it must be marked with the " NA 1993" identification number.


You also state, according to the driver of the cargo tank, the Pipeline and Hazardous Materials Safety Administration (PHMSA) stated in its Reference No. 00-0208 clarification letter that marking the vehicle with " UN 1203" is permitted when all of its compartments contain " NA 1993" diesel fuel under former § 172.336(c)(6). You ask if the driver’s understanding of this letter is correct. The answer is no. The clarification letter PHMSA issued under Reference No. 00-0208 applies to a marking exception for the display of an identification number on a multi-unit cargo tank containing different as opposed to containing the same liquid petroleum distillate fuels in all of its tanks. Therefore, a multi-unit cargo tank that contains the same material, e.g., " UN 1993," in each compartment must be marked with the identification number " 1993."


I hope this information satisfies your request.




T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division


172.336(c)(6), 172.336(c)


DMS ID# 14-0178

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