API/EI 1585-2007

This publication is intended to give operators of airport fuel hydrant systems guidance in:

(a) Determining the state of cleanliness of existing hydrant systems and possible causes of contamination.

(b) Methods of cleaning hydrant systems that are showing signs of contamination with particulate material, water and microbiological material.

(c) Methods to be followed during construction of new systems or extensions to existing systems to prevent the entry of unwanted materials.

(d) Commissioning procedures.

(e) Operational practices to maintain the system in a clean condition.

(f) The design of hydrant systems to aid cleaning.

If the hydrant system is clean when placed in service and adequate filtration is given to the fuel entering it, the hydrant should remain clean in service. In general, only if users are experiencing shorter than normal fuelling vehicle filter element life, or are obtaining unsatisfactory samples upstream of their filters, need action be taken. It should be recognised that submicronic particulate will never settle and will eventually be carried to the users’ vehicles. On the other hand, larger debris may never come out so ensuring that none is present is the best way of preventing problems. Such material in the system may provide an environment to trap moisture and promote microbiological growth.

The key to successful cleaning of supply lines and hydrant systems is to fully understand the subject facilities and to develop a detailed implementation plan with objectives, expected results and how the results will be measured. Hydrant operators should formulate their own procedures, which should be incorporated in manuals and operating procedures. In order to assist, it is essential that 'as built' drawings and associated records are produced after initial construction and that these are kept up-to-date following any subsequent modification.

Training is very important; hydrant operators should be properly trained to recognise signs of trouble and to act upon information and advice regarding fuel quality and the state of pits etc. from hydrant users.

It cannot be too strongly stressed that the key is to ensure that the hydrant system is clean in the first place.