scope:

PURPOSE

The purpose of this publication is to allow a comparison between the procedures adopted by NATO countries for purging Liquid Oxygen Storage and Transport Tanks and Aircraft Converters. The comparison is essential because purging procedures differ widely from country to country and, so far it has not been possible to agree on

standardization.

FOREWORD

The lack of uniformity in purging procedures was addressed at the 13th

meeting of the MAS Aircraft Gaseous System Working Party (GGSWP). An investigation conducted prior to that meeting had revealed what considerable differences existed between the types of gas used their purity and the periodicity of purging. MAS Study 3725 was therefore initiated, with Italy as its custodian. The purpose of the study was to standardize the methods of purging to ensure that any contamination did not exceed the limits of safety. However, it was impossible to achieve

a common procedure for purging.

At the 15th GGSWP meeting it was recommended that the results of the

Study should be compiled into a single document, published under NATO aegis, to document the different national purging procedures and thus stimulate an exchange of information. The document could also improve interoperability should the need arise to exchange Liquid Oxygen (LOX) and/or its related handling equipment within NATO. For ease of reference, the material has been divided in to 3 Tables at Annexes A, B, and C as follows:

Annex A - Purging of LOX Storage Tanks Annex B - Purging of Aircraft Lox Servicing Trailers Annex C - Purging of Aircraft Lox Converters