The Buildings Research Establishment report referred to was prepared in October 2003 for the Department of Health as part of the Aviation Health Working Group. It described a study to monitor cabin air quality aboard older aircraft types utilised in high volume short haul operations, as recommended by the House of Lords report on Air Travel and Health. The report found no obvious difference in the cabin environment between older types of aircraft and newer types and that overall, levels of measured air pollutants were always below any recommended health limits.
The report can be found on the Department for Transport website at:
http://www.dft.gov.uk/pgr/aviation/hci/hacc/bre/.
The Aviation Health Working Group will be commissioning a separate study of cabin air later in the year.
The DHL instruction referred to has been assessed by a CAA flight operations inspector as part of the full range of company instructions relating to smoke, fumes and air contamination. The instruction was promulgated as follow up information additional to the relevant normal, abnormal and emergency procedures. These include company guidance for the use of oxygen and masks. The inspector found the instruction acceptable in that context and the operator has taken steps to ensure in training sessions that it must not be interpreted as a dilution of the company's safety policy with regard to the reporting of incidents of this type.