HC Deb 30 June 1999 vol 334 cc160-1W
Mr. Dalyell

To ask the Secretary of State for Defence, pursuant to the letter of 3 October 1998, D/MIN/(DP)(TG)/3521/98M, on atmospheric pollution, what collaborative research and development programmes aimed at identifying further alternatives to ozone-depleting substances in the applications where they are still necessary have been carried out in the last nine months; and what reduction has taken place in controlled substances where acceptable alternatives are available. [87386]

Mr. Spellar

[holding answer 29 June 1999]: In my response to the hon. Member's earlier question on this subject on 18 January 1999, Official Report, columns 312–13, I reported on the continuing progress made by the MOD in reducing its use of ozone depleting substances.

Since the beginning of the year, a number of CFC and halon systems have been converted to alternative substances. The Royal Navy has completed the conversion or replacement of refrigeration plant on HMS Fearless, HMS Illustrious, HMS Leeds Castle, HMS Sultan, HMS Lancaster and RFA Black Rover. Modification kits have been procured for conversion of refrigeration plants on HMS Spartan, HMS Torbay and HMS Trenchant, and for a chilled water plant on HMS Spartan. Installation of a new chilled water plant has started on HMS Torbay. Action has been taken to procure the kits for conversion of refrigeration plants on the Type 23 frigates. The Army has completed trials of alternatives to halon fire extinguishants for use in in-service armoured vehicle engine compartments and an acceptable fire extinguishant has been identified. A programme of work to convert these systems is now being drawn up. Work to convert CFC environment cooling systems in armoured vehicles has also started. The Defence Procurement Agency has completed the majority of its trials of alternative refrigerants in equipment for which it is responsible and the final report on the conversion of the Challenger 2 engine fire protection systems is expected during July. The Royal Air Force has completed the conversion of refrigerators on all but two of the E3 Sentry aircraft; these remaining aircraft will be modified as soon as operational commitments allow. In a number of cases, equipment that used ozone-depleting substances has been decommissioned as surplus to requirements. At DERA Chertsey, for example, this has reduced the installed quantity of CFC refrigerants by approximately 230 tonnes.

The use of CFC refrigerants will be necessary until conversion programmes can be completed or, where conversion is not technically and economically feasible, until equipment is removed from service. For halon systems which protect, amongst others, existing aircraft, ship machinery spaces and armoured vehicle crew compartments, acceptable alternatives have not been identified, despite considerable international effort. The MOD Corporate Research Programme is funding a study by DERA into alternative fire extinguishants for use in normally occupied enclosed spaces. The study has identified two classes of material with promising fire extinguishing properties. These are the tropodegradable bromoalkenes and a range of phosphorus-containing compounds. The aim is to identify one or more chemicals with good performance and acceptable toxicological and environmental characteristics. This work is being undertaken in close collaboration with the US Advanced Agent Working Group and the US Department of Defence's Next Generation Fire Suppression Technology Program. The Royal Navy continues its sponsorship of research into water mist technologies for potential use in fire protection in new warships. The work has demonstrated that low pressure fine water spray systems with certain additives can give a very effective performance and this work will be validated with real-scale tests over the next 18 months. Close contact is being maintained with the US Navy and US Coast Guard who are also developing water-based technologies for use in future ships.