WPC@ 2B JCourierCG TimesAlbertusCG Times Bold@`7 @1|HPLAS4L.PRS4i6X@`7\-R @ .,., USUK 3'3'Standard6&6&StandardrJet 4Lzư 2iC EGWzz1|CG TimesAlbertus2M Z  uXHP LaserJet 4LHPLAS4L.PRS4Xh4 P*>E\-RP"4|Jx ^ENluuNNNuNNNNuuuuuuuuuuNNhN[}NNNuuNhuhuhNuuAAuAuuuuV[AuuuuhhuhuNuuuuuNuuuuuuuuuAhhhhhhhhhhNANANANAuuuuuuuuuuhuuuuuughggghhghhguuuuuuuuNANANANA[uATAFAuuuuuTTV~Y~Y~Y}[TAAuuuuuuuggguAuV}[AuuuuNuuNNNWxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxNuuuNh__uuuuuuRuuuuRNNyyu<<uuuuuNyuR"uyuuNNNuuuuNuhulcuhhNNNNh[huhNAhhuhuuuhh[uAAhhhhNNuuuuuuu[[[[[[[uuuuuuuuuuuuuuuuuuuuAAAAAAAAAAAAhhhhhhhhhhhhhhhhhhhNNuhN /;k  PP8~~*k~~KkKk&&pY"4|Jx ^;C]ddCCCdCCCCddddddddddCCY~~vCN~sk~CCCddCYdYdYCdd88d8ddddJN8ddddYYdYdCdddddCddddddddd8YYYYYY~Y~Y~Y~YC8C8C8C8ddddddddddYdddddsdXYXXXYYx|X~Y~Y|XddddddddC8C8C8C8oNd|8|H~8<|8dtddddHHJlLlLlLkN|H|8~8dddddddXXXd~8dJkN~8ddxddCddCCCWxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxNdddCYQQddddddFddddFCChhd44ddzzdddvooChdF"dhddCCzCddoddCdYds]zUvdYYCCCCz~ozoY~NYdYC8YooYdYzsdzdd~YYzozzzzNd88YYYzYzzzzCCdddddddzzzzzzzzzzzzzzzzzzzNNNNNNNdddddddddddddddddddd888888888888YYYYYYYYYYYYYYYYYYYzzzzzzzzzzzzzzzzzzzzCs~CzdYC\   pxtll\tll@\@\`L6TANE,U PE37P6U8wC;,WXw PE37XP>V)|C?, 1X|L@ PI37XPt7zC;,(Xz_ pi7X2= 6j & 2"4|Jx ^??d~~?QQ~???Y~~~~~~~~~~??]soh?Qkh~h~zUYUdd?]k]o`?`k00`0kookJFCk``dNYdY~?~~~~~?~~~~~~d~v0]]]]]]o`o`o`o`?0?0?0?0kooookkkkd]toodohol]lll]]tlo`o`tl`t````kk80?0?0?0`Q`l0lDk0kJzFttktoHH~JdhFdhF|P|H~Cktkktkdx`zNx`ok0k~JhF~Cddok?dd???WxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxNd~~?]]]~~~NN~N]dd~N??kk~44~~zzdddvkk?kdN"dsddCCv?dho~d?kd~skzUvdYYQQUUoskodko]zUsk?0dhoo~UsshkvvY~]k`o]s00skkko??~~~~~~~ooooooooooooooooooo]]]]]]]ssssssssssssssssssss000000000000ssssssskkkkkkkkkkkk?so?dYC\   pxtll\tll@\@\`L"4|Jx ^;C]ddCCCdCCCCddddddddddCCdxN`xoCCCddCdoYoYFdo8Co8odooYNCodddYddddCdddddCddddddddo8dddddYYYYYN8N8N8N8oddddooooddpddddxodddXXYYXYYXddddddooL8N8N8N8r`o8P8N8ppoddXXYpLoNpLoNPDCopoopodXYXo8oYoNCdddoCddCCCWxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxNdddCdUUddddddFddddFCCssd44ddzzddd~ooCsdF"dsddCCzCddoddCdYds`zUvdddCCCCzozoYNYYYN8YooYdYzzdzddYYzozzzzNY88YYYzYzzzzCCdddddddzzzzzzzzzzzzzzzzzzzNNNNNNNYYYYYYYYYYYYYYYYYYYY888888888888YYYYYYYYYYYYYYYYYYYzzzzzzzzzzzzzzzzzzzzCzNzdYC\   pxtll\tll@\@\`L"4|Jx ^ENluuNNNuNNNNuuuuuuuuuuNNu[pNNNuuNuhhRuANAuh[NuuuhuuuuNuuuuuNuuuuuuuuAuuuuuhhhhh[A[A[A[AuuuuuuuuuuuuugghhghhguuuuuuYA[A[A[ApA]A[AuugghY[Y[]ONughgAh[NuuuNuuNNNWxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxNuuuNuccuuuuuuRuuuuRNNu<<uuuuuNuR"uuuNNNuuuuNuhupcuuuNNNNh[hhh[Ahhuhuuuhh[hAAhhhhNNuuuuuuu[[[[[[[hhhhhhhhhhhhhhhhhhhhAAAAAAAAAAAAhhhhhhhhhhhhhhhhhhhN[uhN /;k  PP8~~*k~~KkKk&&pY2Z1>J@6TANE,U PE37P6U8wC;,WXw PE37XP>V)|C?, 1X|L@ PI37XPt`7zC;,(Xz_ pi7Xt@NE,?_ pi7 X  3'3'Standard6&6&StandardHPLAS4L.PRS4Xh4zư 6&6&StandardHPLAS4L.PRS4Xh46&6&StandardrJet 4Lzư  b  +  #Xw PE37WXP#  3 3 ;;#',CC04RESTRICTED   3 3 ;;#',CC049   3 3 ;;#',CC04ST/SG/AC.10/R.485   3 3 ;;#',CC045 October 1994   3 3 ;;#',CC04ENGLISH ONLY COMMITTEE OF EXPERTS ON THE TRANSPORT OF DANGEROUS GOODS (Geneva, 28 November 7 December 1994, agenda items 3 (c) and 9) PROGRAMME OF WORK l DIVISION 5.2 ORGANIC PEROXIDES  Proposal to reclassify DItertBUTYL PEROXIDE (DtBP) to enable bulk transport of the products 1 Transmitted by the European Chemical Industry Council (CEFIC)   CEFIC proposes that the proposal reproduced below should be discussed in the next biennium. GE.94 a:\R.485E()))bb ST/SG/AC.10/R.485 page 2 4 bN  6&6&StandardrJet 4L6&6&StandardHPLAS4L.PRS4Xh4z+N  +# #Xw PE37WXP# 1 SUMMARY & INTRODUCTION Technically pure ditert butyl peroxide ( DtBP ) has been transported in bulk within the UK since 1984 using specially adapted 13 m3 tank containers. The decision to allow the bulk transportation of the product under the old ADR was taken after fire engulfment trials carried out by Laporte Industries in 1979 1981 on one tonne containers. Some of these trials were witnessed by the HSE. (refs 5.1 5.3). In giving approval the HSE set the criteria that " the contents of the tank should not exceed 50C after one hour's fire exposure". The current "Recommendations on the transport of Dangerous Goods" issued by the United Nations Organisation no longer permits the carriage of DtBP in tank containers as the product has been given the generic classification UN 3107.  X; Nevertheless, a review was #Xx1XP#carried out on the requirements for Class 5.2 ( Organic Peroxides ) with special consideration of likely emergency scenarios which should be taken into account when designing a suitable tank container especially with regard to the emergency venting devices. This process has involved the development of much new experimental evidence on the behaviour of DtBP. A number of scenarios have been examined, calculations made and experimental work carried out to establish an adequate design basis for emergency relief devices. <)))bb $$ | |  ,,"44'+/ST/SG/AC.10/R.485 $$ | |  ,,"44'+/page 3 In particular, a special study was made of the existing FMC tank containers in use for the transport of DtBP. Within this current report, reference is made to the design features of these containers as illustrations of how adequate safety can be built into the design of tank containers. A technical report (ref. 5.4) was issued for review by the HSE. This report recommended that transport of DtBP in bulk would be essentially safe in the existing tank containers once additional relief venting was fitted and that on fitting two temperature sensing devices the containers would otherwise comply with the UN Code. After review, the HSE issued an exemption for the time being permitting bulk transportation within the UK on the understanding a formal reclassification of the product was progressed through the UN. Since then, the topic has been discussed with IGUS and additional work has been carried out to confirm the basis for sizing emergency relief vents for deflagration. It is not without precedent for the UN Committee to accept a substance into a generic group different from the one using the UN Classification method. Therefore, the UN Committee is asked to review the findings of this report and agree to a reclassification of DtBP to UN 3109 subject to the suggested marginals. 2 TYPES OF ORGANIC PEROXIDES ALLOWED FOR TRANSPORT IN BULK Organic peroxides and organic peroxide formulations which are currently assigned to the generic entry UN 3109 in Tables 11.3 and 11.5 of the UN Recommendations may be carried in tank containers. DitertBUTYL PEROXIDE (>32 100%) is currently assigned in Table 11.3 the generic entry UN 3107 not permitted in bulk. In the case of substances not so listed, UN 11.3.2.5 requires that tests should be carried out for assignment of the new organic peroxide or peroxide formulation to Class 5.2 and that the test criteria according to the UN Recommendations should be applied. To be considered for transport in tank containers, the product should meet the criteria for exit box F of the UN classification flow chart, namely: )+++ ST/SG/AC.10/R.485 page 4 $$ 4 it does not detonate in the cavitated state $$ it does not deflagrate $$ it shows no or low effect when heated under confinement $$ it shows no or low explosive power DtBP, technical pure has been subjected to these tests. The results confirm the official classification as a type E formulation. The only reason that this is true is because the explosive power is determined to be NOT LOW box 8. (It has a value of 140 J/gm when measured by the High pressure autoclave test method). Had the explosive power been LOW then the classification would be type F. This report examines a number of scenarios whereby the explosive power of DtBP could be released. It finds that it is possible to design a suitable tank container with adequate emergency venting for all but one extremely improbable event. The whole purpose of the UN Classification method is to provide a sensible framework for classification into generic groups and avoid the need for case by case consideration. However, it is not without precedent for the UN Committee to accept a substance into a generic group different from that determined by the flowchart. Therefore, the UN Committee is asked to review the findings of this report and agree to a reclassification of DtBP to UN 3109 subject to the suggested marginals. 3 EMERGENCY SCENARIOS 3.1 FIRE ENGULFMENT FOR ONE HOUR The UN Code requires that emergency vent devices are capable of venting all decomposition products and vapours evolved during a period of not less than one hour of fire engulfment and selfaccelerating decomposition. Given that technically pure DtBP has an explosive power that is NOT LOW, consideration has been given to what other emergency scenarios might occur in transit. Special account has been taken of the possibility of vapour explosions, in air or nitrogen. The effect of fire exposure has been simulated both mathematically (full scale) and experimentally on a 8.3 litre scale for the FMC tank container with the received energy exactly in accordance with the UN regulations, namely 110 kW/sqm over the full area of the tank. The mathematical simulation results are in line with those observed during fire engulfment trials on one tonne containers using the same insulation material. (ref. 5.1 5.3.) According to the UN recommendations, calculations must assume that 1% of the tank insulation is damaged. The code does state which part of the tank. *+++Ԍ$$ | |  ,,"44'+/ST/SG/AC.10/R.485 $$ | |  ,,"44'+/page 5 If the damaged area is wetted, after one hour's fire exposure, the average liquid temperature would reach about 32C. The original HSE requirement "that the contents of the tank should not exceed 50C after one hour's fire exposure " is clearly met under these conditions. The SADT for the FMC tank has been calculated as 65C. On removal of the fire condition the tank would cool down safely. Further it can be shown that the rate of decomposition of DtBP at 50C is only 0.06kg/hr for the 9400 kg tank contents this would yield a pressure buildup in the tank of less than 0.03 bar and so no release of vapours would occur. The decomposition rate is well within the capacity of a pressure relief valve. Thus meeting the requirements of UN para 12.557 Pressure relief devices should be fitted to prevent a buildup of decomposition gases and vapours released at 50C. On the other hand, if part of the damaged area is in the vapour space, this will rapidly cause a "hot spot", leading to a gas phase deflagration once the liquid is above it's flashpoint followed by a deflagration in the liquid. Since the flashpoint of DtBP in air is 6C and its autoignition point is 165C, such a deflagration would soon occur leading to a serious event (activation of the emergency relief device and release of material) Hence, using a marginal, it is recommended that DtBP is carried under a nitrogen gas blanket. When inerted with nitrogen, the 'flashpoint' of DtBP is raised to 55C, a temperature which would not be reached on one hour's fire exposure. 3.2 FIRE ENGULFMENT FOR TWO HOURS OR MORE If the damaged area is wetted, after two hours the average temperature would reach 56C. This is still below the SADT and so the tank would cool down on removal of the fire. If part of the damaged area is in the vapour space, hot spot ignition leading to a gas phase deflagration once the liquid is above 55C, a temperature which would be reached after about two hour's fire exposure. For this reason, a second marginal is recommended i.e. that the emergency vent device must be sized for a liquid phase deflagration at 60C. Cases where the fire exposure continues much beyond two hours have also been examined. Calculations show emergency relief devices can be designed with sufficient capacity to take account of selfaccelerating decompositions as a result of either the SADT being exceeded or a continuous fire. The investigations have confirmed the value of limiting the set pressure of the device to 1 bar gauge so minimising the relief temperature and, thereby, the rate of decomposition. ST/SG/AC.10/R.485 page 6 In the case of the FMC tank containers, a 0.154m diameter bursting disc set at 1.0 bar gauge pressure is fitted and has been shown to be adequate for all the above situations. 3.3 WORST CASE SCENARIO The investigations have found one event where emergency relief devices could not protect the tank container. This is when either prolonged heating or massive loss of insulation brings the liquid contents to the boil and a virtually instantaneous deflagration is caused by ignition of the vapour phase. The probability of such an event is considered to be low enough to ignore because it requires a combination of two other low probability events namely fire engulfment for over three hours and a lack of a hot spot ignition of the container contents at a lower temperature when the emergency vent device could cope. 3.4 SUMMARY OF EMERGENCY SCENARIOS A tank container can be designed to withstand a one hour fire engulfment without incident even if the insulation is damaged to provide 'hot spots' in the vapour space. The key factors are to provide an inert atmosphere above the tanks contents at all times and to ensure that the liquid contents of the tank do not exceed 50C after one hour's fire engulfment. These are the reasons for the requested marginals x/ and y/ on page 263. In a longer fire, liquid deflagration caused by a 'hot spot' is possible once the temperature exceeds the 'flashpoint' or 55C. For this reason marginal z/ is included to ensure that the emergency device is designed for liquid phase deflagration. The probability of the worst case scenario is considered to be low enough to ignore. 4. REQUESTED CHANGES TO THE UN RECOMMENDATIONS On page 254 Table 11.3 against DItertBUTYL PEROXIDE concentration >32 100%: $$ The Packing method should be amended to OP8A,M $$ The generic entry 3107 should be changed to 3109 X$$ The subsidiary risk and remarks should include a marginal entry reference e.g. n) where n is the number of the next available note on page 258Ɵ#$ On page 258 add to the list of notes under entry n) the following expression: X$$ assigned to ORGANIC PEROXIDE TYPE F on the basis of a detailed technical investigation and one tonne fire engulfment trials.Ɵ#$*+++Ԍ$$ | |  ,,"44'+/ST/SG/AC.10/R.485 $$ | |  ,,"44'+/page 7 On page 263 Table 11.5 add to the list under UN 3109: X$$ Ditertbutyl peroxide x/,y/,z/. 32 100 %Ɵ#$ X$$ where x/,y/ and z are the next available notes under the table.Ɵ#$ On page 263 under Table 11.5 add the notes: X$$ x/ use a nitrogen blanket at all times to exclude airƟ#$ X$$ y/ the liquid contents of the tank should not exceed 50C after one hour's fire exposureƟ#$  X$$ z/ emergency vent device must be sized for liquid phase deflagration when the liquid contents are at 60CƟ#$ REFERENCES  J 5.1X$$ Wilberforce J.K., Manley T.D.,Ɵ#$ X$$ Fire Engulfment Trials at Glebe Mines Derbyshire November 1979 Report of Laporte Industries Limited.Ɵ#$  J 5.2$$ Wilberforce J.K., Manley T.D., X$$ Insulated DtBP Tanks Fire Engulfment Trials at Glebe September/October 1980 Report of Laporte Industries Limited.Ɵ#$  JN 5.3$$ McGahan A.E. X$$ Visit Report on fire engulfment trials for HSE at Harpur Hill 28/January/1981Ɵ#$ X$$ CibaGeigy Industrial ChemicalsƟ#$  J 5.4$$ Steensma M., Bollen A.G., X$$ Report for the HSE prepared to support an application to allow the continued use of three FMC isocontainers for the transport of pure ditertbutyl peroxideƟ#$ $$ July 1992 AKZO Chemicals BV 5 ă