Select Committee on Science and Technology Written Evidence

Letter from H&S Representative T&G section of Unite the Union

  You may be aware that Unite the Union is the only union representing cabin crew staff on British registered commercial aircraft and has been a member of the Aviation Health Working Group since 2004 as the Transport and General Workers Union.

  This evidence enhances that submitted by the Transport and General Workers Union (T&G) and Amicus Sections of Unite—the union on Cabin Air Quality.

  Further to the invitation by the Select Committee for "evidence on the health effects of air travel" we would like to specifically address concerns about the efficacy of the Aviation Health Working Group(AHWG) and cabin air quality.

  Despite the Draft Mission Statement for the Aviation Health Working Group[141] stating:

    "The Aviation Health Working Group will meet on a regular basis and will work in partnership with other interested parties to give effect to the Government response to the House of Lords Inquiry into Air Travel and Health."

  the AHWG has not met on a regular basis nor worked entirely in partnership with other interested parties. On the latter point the Independent Pilots Association, prevented from joining the AHWG unlike the British Airline Pilots Association who are able to attend, is the only other UK union representing flight crew. They are very much an interested party in all aviation health issues. We firmly believe there is a continuing need for simple and effective communication about Aviation Health and it is of paramount importance that this be facilitated by regular meetings of the AHWG.

  As to cabin air quality it is noteworthy that whilst the House of Lords Report (HL Paper 121) called for:

    "9.3(c) real-time monitoring of air quality (see paragraph 5.50) and other aspects of the cabin environment, with a view to establishing new and clear regulatory minima for passenger cabin ventilation"

  the lack of equipment capable of undertaking this task was emphasised over 5 years ago[142] at the meeting on 16 October 2002 chaired by Peter Smith:

    "On the `collection of basic cabin environment data' [recommendation 1.25), Nigel Dowdall outlined the lack of available equipment to provide the sort of `routine monitoring' recommended by the House of Lords. He indicated that material had been published on a number of websites including BA's, Boeing's and also in a number of articles and journals. He also confirmed that this material would include some of the routine data continuously monitored on-board flights. The Secretary confirmed that MLD had received a list of websites from BATA, and the Chair concluded that this action point had been achieved."

  and, it is understood, nothing has changed.

  At paragraph 3.33 the House of Lords Report stated:

    "Until 1996, both FAA and JAA had the same basic requirement for cabin ventilation rates. FAR 25.831 and JAR 25.831 required a minimum supply of 10 cubic feet per minute (cfm)[26] [27] of fresh air per flight crew member, which `must be free from harmful or hazardous concentrations of gases or vapours' with specific maximum concentrations for:

    —    carbon dioxide at 5,000 parts per million by volume (ppm)[28];

    —    carbon monoxide at 50 ppm; and

    —    ozone at 0.1 ppm (short-term emergency maximum 0.25 ppm)."

  and yet, to this day, carbon monoxide detectors are not fitted to commercial aircraft and in answer to a written question by Lord Tyler the Government have indicated they have no intention of ensuring such detectors are fitted in the majority of commercial aircraft:

    "Lord Tyler asked Her Majesty's Government: What steps they have taken to ensure that carbon monoxide detectors are fitted in aircraft to enable the commander to monitor emissions. [HL1941]

    Lord Davies of Oldham: The Civil Aviation Authority (CAA) has recently drafted a European Technical Standards Order (ETSO) that provides an up-to-date technical specification for a carbon monoxide detector for aviation use. This draft ETSO has been submitted to the European Aviation Safety Agency (EASA) with a recommendation for adoption as a European standard. At the same time the CAA submitted a proposal for changes to EASA's certification specifications that would mandate the installation of carbon monoxide detectors in future aeroplane designs.

  These proposals were made as a direct result of experience of accidents, and they were supported by a preliminary Regulatory Impact Assessment. The proposals, if adopted, would require installation of carbon monoxide detectors only in single-engined aeroplanes with forward mounted engines, since the world-wide experience of accidents and incidents does not support the need for installation of carbon monoxide detectors in other aircraft."

  Government further confirmed that aircrew relied on their sense of smell to determine whether a contaminated air event was taking place and that there is no requirement for fitting air quality monitoring equipment, or for air crew to be tested during their mandatory medical for a sense of smell:

    "The Countess of Mar asked Her Majesty's Government: Further to the Written Answer by the Lord Davies of Oldham on 19th October (WA 126), how, in the event of a system failure and a contaminated air event occurring, aircrews know that such an event has occurred in the absence of monitoring devices when the contaminated air is caused by compounds, such as carbon monoxide, that have no odour. [HL2313]

    Lord Davies of Oldham: In the absence of odour, and in the absence of any discernible effects, aircrew will not know that a contaminated air event has occurred. In such a case reliance is placed upon routine maintenance actions to find and fix the system failure.

    The Countess of Mar asked Her Majesty's Government: Why contaminated air detection systems are not fitted to all British commercial aircraft. [HL1641]

    Lord Davies of Oldham: There are no statutory requirements for the fitting of air quality monitoring equipment in aircraft. Such equipment is not required because aircraft ventilation systems are designed to supply air of an acceptable standard. This is confirmed at initial certification and each aircraft is subject thereafter to scheduled maintenance actions to ensure those standards are maintained. Air quality monitoring exercises have confirmed the acceptability of cabin air supplied. Where problems are encountered in service these are investigated and changes are introduced as necessary."

  In consequence, it is quite clear that, despite specific maximum concentrations for ozone, carbon monoxide and carbon dioxide being stated (3.33), there is still no real time equipment installed to monitor, control, or warn flight crew if these levels are exceeded. Additionally, there is no warning possible of a contaminated air event when substances hazardous to health, such as Tri-cresyl phosphate (TCP), enter the cabin.

  Furthermore, and relevant to the House of Lords Report (9.3(e)), there has been little consideration of the synergistic effects posed by chemicals:

    "The Countess of Mar asked Her Majesty's Government: What exposure standards currently apply to any synergistic effects of simultaneous exposure to numerous chemicals which may be experienced by aircraft passengers and crew during a contaminated air event in a reduced pressure environment. [HL1761]

    Lord Davies of Oldham: None. European airworthiness regulations for aircraft and engine design are written in objective terms that stipulate that the air provided to the passenger and crew compartments must be free from harmful or hazardous concentrations of gases or vapours."


  1.  The T&G take the issue of the health and safety of its members, and indeed the travelling public, very seriously. We remain exceptionally concerned that the breathing air supply to the cabin, provided by bleed air, is delivered completely unfiltered and that both this supply and any recirculated air is not monitored to ensure it is "free from harmful or hazardous concentrations of gases or vapours." Current detection of potentially contaminated air relies on the nasal passages of the crew and that is not acceptable.

  Contaminated air events continue to happen on commercial aircraft.

  2.  We trust the AHWG will meet on a regular basis and will work in partnership with other interested parties.

17 June 2007

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