Offshore helidecks - testing of helideck foam production systems

Offshore Information Sheet No. 6/2011

(Issued August 2011)

Contents

• Introduction
• Background
• Action
• Relevant legal requirements
• References
• Annex

Introduction

1. This Offshore Information Sheet is to remind duty holders of the need to ensure that the testing of the quality of offshore helideck firefighting foam concentrates and mixing/induction systems are fit for purpose. It replaces Safety Notice 2/2004 which is withdrawn.

Background

2. Foam systems need to be tested in two ways, firstly by ensuring the system is in working order and secondly by analysing samples of foam concentrate and finished foam. The discharge of significant quantities of finished foam to the sea has potential  to pollute the environment. Therefore the methodology for testing foam and equipment performance should be carried out  with a view to minimising the potential for pollution to occur.

3. Systems should be tested and quality assured before installation to ensure that foam (particularly 1% inducted) meets its performance parameters. This would normally be done onshore, with the finished foam contained and suitably treated.

4. Routine periodic testing of performance in the offshore environment should be achieved by operating the equipment initially using water only and subsequently confirming by production of a limited amount of finished foam captured for testing. Testing of this finished foam and a sample of the foam concentrate should be conducted by an accredited foam test house against the applicable laboratory standard (eg BS5306, NFPA11 etc.)

Action

5. Duty holders should:

• review their existing management systems and test procedures against CAP 437 (Chapter 5, Helideck Rescue and Firefighting Facilities), together with the Annex to this Offshore Information Sheet;
• Ensure that the foam production/induction equipment is maintained and fit for purpose;
• Ensure that the foam concentrate remains within its technical specification.

Relevant legal requirements

Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995, regulation 7 - equipment for helicopter emergencies, and regulation 19 - suitability and condition of plant.

References

• Civil Aviation Authority (CAA) CAP 437 Offshore Helicopter Landing Areas: Guidance on Standards Sixth edition.

Annex

Testing procedures for foam systems

There are two tests of systems, a performance test when commissioned and an in-service (annual) test.

Foam Production Performance Test

1. In order to ensure that foam production is of an acceptable standard a Foam Equipment Performance Test (ie an "Acceptance Test") should be carried out:
   1. When the equipment is installed on a deck.
   2. When significant maintenance, refurbishment or component replacement has been undertaken that could effect a change in the foam quality or production performance of the foam-making System. This includes a change of foam-making branches, nozzles or monitors. Only those parts of the system that could have been affected by the work undertaken or the component change need to be tested.
2. The Foam Equipment Performance Test should confirm the following:
   1. The induction percentage for all foam-making devices.
   2. The jet range of the monitor/s.
   3. The spray pattern of the main monitor/s.

In-Service Test

1. In-Service (annual) test should be conducted to ensure the quality of the foam concentrate and the performance of the equipment.
   1. Samples of foam concentrate should be representative of the parent stock. A foam drum should be rolled or agitated to produce a homogeneous mix before drawing a sample from the top. For bulk foam storage tanks circulate the contents to produce a homogeneous mix before taking a sample. Alternatively draw samples from the top, middle and base. Use a hollow tube to take a sample from the middle. For the base sample use a side-exiting outlet pipe or alternatively run-off about 25 litres of foam first to remove any accumulated sediment. This run-off may be returned to the top of the tank. Several samples may be mixed equally to produce a single composite sample of 500ml.
   2. A small amount of finished foam should also be collected by placing a sample collector in the discharge area. Sufficient finished foam should be collected to provide a 500ml sample of foam. This sample should be used to check the percentage concentration in the finished foam.
   3. Samples should be clearly labelled as concentrate or finished foam, origin, foam type, and recommended induction rate.
   4. The tests should confirm that the system produces foam, within permitted tolerances, to the original technical specifications
   5. The foam production equipment should be activated using water only to confirm the jet range and spray pattern of the system.