Doc. 184/18Methods to Prevent the Premature Activation of Relief Devices on Transport Tanks

It is important to ensure that prior to transport, particularly by rail or sea, UN portable tanks, tank containers and demountable tanks are adequately prepared for shipment to prevent the premature activation of any relief devices and that the time before the relief devices would be expected to operate is determined.

 Premature activation of relief devices can lead to delays of the shipment, loss of product and disruption to transport services.

 There are specific requirements in the transport regulations to address holding times and this publication is intended to assist in the interpretation of how these are applied.

 This publication applies to tanks transported primarily by rail and sea, where the pressure of the tank cannot be controlled during the transport operation as they are unaccompanied.

 Tank vehicles (road vehicles) are excluded from this document, however the principle to lower the pressure prior to any form of carriage also applies so as to prevent premature operation of the safety devices.

 This revision includes the relevant text from ADR, additional information on foam insulation and advice on vacuum insulted tanks. As well, guidance is given on preparation for journeys and clarification of empty tanks.

 This publication is intended for all those who are responsible for the shipping of UN portable tanks, tank containers and demountable tanks to ensure the maximum holding time is achieved.