In addition to the requirements for proper marking and colour-coding, there is a need throughout the aviation industry, in general, for uniformity in product labels. The aviation gasoline (Avgas) and turbine fuel (Jet Fuel) labelling system included herein for aviation use is recommended for worldwide use, not only for aviation fuel handling equipment at airport fuel storage facilities, but for all situations where it is desirable to identify Avgas and Jet Fuel by type and grade. It is intended to apply to equipment that is in continuous use for a single grade of aviation fuel, e.g.:

— Airport depots.

— Airport fuel hydrant systems.

— Airport fuelling vehicles.

— Dedicated grade aviation fuel storage tanks and piping within terminals.

— Dedicated grade aviation fuel loading facilities at refineries, terminals or airports, etc.

It is not intended to apply to equipment that is not in continuous aviation fuel use, e.g.:

— Refinery storage tanks and associated piping.

— Multi-product pipelines.

— Non-dedicated loading facilities, etc.

For further information on labelling systems for equipment not in aviation use see the latest edition of either API RP 1637 Using the API color-symbol system to mark equipment and vehicles for product identification at service stations and distribution terminals, or IP Code of practice for a product identification system for petroleum products.

— Fully collapsible.

— Type A hoses.

— Type B hoses.

The specifications of this standard are intended for the convenience of both manufacturers and users. Users and manufacturers are not prohibited from purchasing or producing hoses that conform to other standards. The user should refer to the Rubber Manufacturer’s Association Hose Handbook, and other specifications.

Each purchaser should conduct test verifications independent of any tests or inspections performed by the hose manufacturer. Such user tests should be performed in accordance with this standard.

1. Selected aspects of dirt defence filter element performance.

2. The general mechanical specifications for dirt defence filter elements.

3. Laboratory tests and minimum performance requirements for the qualification of new dirt defence filter elements.

4. Requalification and similarity requirements. The laboratory tests specified in this publication are intended to provide standard methods of evaluating selected aspects of the performance of new dirt defence filter element designs, which may be relevant to field service. They are not intended to predict the actual performance of dirt defence filters in field service. Aspects of field performance including dirt removal efficiency and service life vary with different operating environments. Users should work with their suppliers to ensure that their application of dirt defence filters provides the performance needed in the particular application.

The scope of this publication is limited to elements of 50 mm (2 in.) nominal diameter up to 76 cm (30 in.) nominal length flowing out-to-in, and 150 mm (6 in.) nominal diameter up to 145 cm (57 in.) nominal length flowing out-to-in.

This publication does not address:

1. Specific material requirements for the dirt defence filter element.

2. The performance testing of a dirt defence filter system.

3. Maintenance or service life performance.

4. Trigger type elements.

5. Certain aspects of design and performance necessary to provide products that are fit for a particular purpose. Many aspects of dirt defence filter performance are neither measured nor controlled by this publication. Dirt defence filter elements may differ in design in the selection of filtration media used.

This edition of the specification was developed to align API and IP perspectives and clarify certain testing requirements. The test fuel chemistry is changed in this edition to provide alignment with a revision of API/IP 1581 Specification and qualification procedures for aviation jet fuel filter/separators, but no changes in element performance requirements between this and the 1st edition of the specification are intended. Equipment qualified to the 1st edition of this specification remains qualified to this edition subject to purchaser's agreement.

This publication describes specifications and qualification test procedures for microfilter elements of the disposable cartridge type and, separately, the manufacturing requirements for new vessels for use in aviation jet fuel-handling systems. It relates only to elements nominally rated within the range 1,0-5,0 µm. This specification provides test conditions and minimum flow rates for microfilter elements having an outside diameter of 150 mm (6 in.). Microfilter elements of other diameters may fall within the scope of this specification when manufacturer and purchaser agree to minimum flow rates and certain test conditions. These specifications are for the convenience of purchasers in ordering, and manufacturers in fabricating, microfilter vessels and elements. They are not in any way intended to prohibit either the purchase or manufacture of microfilter elements meeting other requirements.

Once an element model has been qualified, any change in design or materials voids the qualification of that model. It may not be necessary to conduct all of the performance tests in this specification to re-qualify a modified model depending upon the details of the changes.

The vessel requirements included in this specification refer to new, purpose built microfilter vessels. This specification does not discourage the use of existing vessels, which continue to meet purchasers’ needs, regardless of compliance with the mechanical requirements of this specification.

This publication specifies microfilter element performance in terms of single element tests only (no full-scale testing is required). This permits the purchaser maximum flexibility in the application of microfilter elements. Purchasers, however, should be aware that the design and application of full-scale vessels could impact field performance. Users should also be aware that the field performance of microfilters is affected by a number of parameters. For example an additive-containing fuel may subsequently disperse dirt particles collected by a microfilter from an additive-free fuel such that particles are released to the fuel stream.

The American Petroleum Institute and The Institute of Petroleum are not undertaking to meet the duties of employers, manufacturers or suppliers to warn and properly train and equip their employees, and others exposed, concerning health and safety risks and precautions, nor undertaking their obligations under local and regional laws and regulations.

Nothing contained in any American Petroleum Institute or Institute of Petroleum joint publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any method, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent.

It is hoped and anticipated that this publication will assist both the manufacturers and purchasers of microfilters. Every effort has been made by the American Petroleum Institute and the Institute of Petroleum to assure the accuracy and reliability of the data contained in this publication; however, API and IP make no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any local or regional laws or regulations with which this publication may conflict.

Suggested revisions are invited and should be submitted to the Manager of Standardization, American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005, USA or to the Technical Department, Institute of Petroleum, 61 New Cavendish Street, London, W1G 7AR, UK.

This publication specifies dimensions, coupling action, activation, and other requirements to achieve the necessary operational requirements and full interchangeability between components from manufacturers of hydrant pit valve assemblies and couplers. It also includes requirements for other optional features which component manufacturers may be requested to provide by purchasers. The performance specifications are for equipment intended for systems in aviation turbine fuel service. They do not apply to aviation gasoline (Avgas).

1.2.2 Organization

If complete interchangeability is to be attained, certain features of the mating components shall be standardised. Other features, although desirable, are not so critical, but are pointed out to assist manufacturers in the design of these components.

The pit valve and coupler, along with any other features attached, are considered to be as a whole for the purposes of this publication.

Section 3 covers general arrangement and features, specifying those features of the hydrant components that are mandatory, as well as those that are optional. They are listed as "Mandatory" and "Optional" respectively. Section 4 describes performance criteria and test requirements for the hydrant pit valve assembly and hydrant coupler. Section 5 contains the quality assurance and information requirements. Five annexes are included for information only.

— Design and construction of filter vessels.

— Vessel accessories.

Although this publication is primarily intended to apply to vessels for civilian applications, many of the requirements may also be applicable to vessels intended for military use. Further advice should be sought from manufacturers for specific military applications.

This publication refers specifically to the use of elements of 50 mm (2 inch) and 150 mm (6 inch) nominal diameters.

The specifications do not cover trigger type monitor elements.

The specifications do not cover the operation and performance of this type of equipment in fuels containing Fuel System Icing Inhibitor (FSII). This fuel additive is unique and makes unusually difficult demands on filtration and water separation/removal devices. Operators using such additives in aviation fuels are recommended to ensure for themselves the performance capabilities of filtration equipment by contacting the filter manufacturer for such in formation.

Note 1: Performance testing of elements of different nominal diameters is outside the scope of this specification. However the test principles described in this document may be adapted to apply to such elements and it is the responsibility of the manufacturer to adjust test parameters accordingly.

Note 2: The document uses S.I. units throughout except where there is no practical conversion equivalent. Where appropriate, alternative units in common usage are given in brackets. Section 4.7 lists the unit conversion factors used in this specification.

This publication applies to two-stage (filter and separator) and the filter/separator stages of multi-stage filter/separator systems. This publication does not apply to monitor and/or prefilter stages that may be present in multi-stage systems.

(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.