Ventilation and health in non-industrial indoor environments: report from a European multidisciplinary scientific consensus meeting (EUROVEN).

Scientific literature on the effects of ventilation on health, comfort, and productivity in non-industrial indoor environments (offices, schools, homes, etc.) has been reviewed by a multidisciplinary group of European scientists, called EUROVEN, with expertise in medicine, epidemiology, toxicology, and engineering. The group reviewed 105 papers published in peer-reviewed scientific journals and judged 30 as conclusive, providing sufficient information on ventilation, health effects, data processing, and reporting, 14 as providing relevant background information on the issue, 43 as relevant but non-informative or inconclusive, and 18 as irrelevant for the issue discussed. Based on the data in papers judged conclusive, the group agreed that ventilation is strongly associated with comfort (perceived air quality) and health [Sick Building Syndrome (SBS) symptoms, inflammation, infections, asthma, allergy, short-term sick leave], and that an association between ventilation and productivity (performance of office work) is indicated. The group also concluded that increasing outdoor air supply rates in non-industrial environments improves perceived air quality; that outdoor air supply rates below 25 l/s per person increase the risk of SBS symptoms, increase short-term sick leave, and decrease productivity among occupants of office buildings; and that ventilation rates above 0.5 air changes per hour (h-1) in homes reduce infestation of house dust mites in Nordic countries. The group concluded additionally that the literature indicates that in buildings with air-conditioning systems there may be an increased risk of SBS symptoms compared with naturally or mechanically ventilated buildings, and that improper maintenance, design, and functioning of air-conditioning systems contributes to increased prevalence of SBS symptoms.

Sickness at high altitude: a literature review.

When some individuals spend just a few hours at low atmospheric pressure above 1,500 m (5,000 ft)--such as when climbing a mountain or flying in a plane at high altitude--they become ill. Altitude sickness studies originally concentrated on life-threatening illnesses which beset determined and athletic climbers at extreme altitudes. In recent years, however, research attention is moving towards milder forms of sickness reported by a significant proportion of the growing number of visitors to mountain and ski resorts at more moderate altitude. Some of this research is also relevant in understanding the problems experienced by passengers in newer planes that fly at a significantly higher equivalent cabin altitude, i.e. 2,440 m (8,000 ft), than earlier designs. Engineering solutions--such as enriched oxygen in enclosed spaces at altitude, or in the case of aircraft, lower cabin altitudes--are possible, but for an economic assessment to be realistic an engineer needs to identify the scale of the problem and to understand the factors determining susceptibility. This review concentrates on the problems of mountain sickness in the ordinary population at altitudes of around 3,000 m (10,000 ft); this is a problem of growing concern as ski resorts develop, mountain trekking increases in popularity, and as higher altitude cabin pressures are achieved in aircraft.

Comfort and health in commercial aircraft: a literature review.

Air travel is becoming increasingly more accessible to people both through the availability of cheap flights and because the airlines are now able to cater for individuals of all ages and disabilities. The wide bodies of many new aircraft permit the airlines to have very flexible seating options. Airline operators currently have an important role in determining the comfort and spaciousness of the seating in their aircraft. Passengers who remain seated for the bulk of a flight may risk oedema or deep vein thrombosis. This could be particularly important for larger people in certain economy class seats. The absence of smoking on planes has encouraged designers to cut back on the rate of cabin ventilation and hence introduce filtered recirculated air to the aircraft cabin. In new planes the ventilation rate is under pilot control and savings (economies) can be achieved by using decreased ventilation. A lower ventilation rate may lead to 'less comfortable air quality' in some parts of the plane and an increased risk of possible cross-infection from other passengers on the flight. Technological advances in jet engine design has permitted larger passenger planes to fly longer distances and at greater altitudes than ever before. The higher flying altitude is associated with a lower cabin pressure, which has an important physiological effect on oxygen saturation in the blood of both crew and passengers, particularly for the very young, the elderly and those who are less fit.

New regulations on water hygiene. Have you applied them?

1. New legislation asks for a named manager to be responsible for water hygiene in buildings. 2. Two reports outline what is required. One, A Code of Practice, lays down a management framework. The other, a Guidance Note HS(G)/70 gives useful background information and proposes in detail what is expected. Valuable practical suggestions for existing plant are given too. 3. Every building should by now have a written risk analysis together with a description of the actions planned to minimise the risk of legionellosis (legionnaires disease or Pontiac fever). 4. Every building should by now have a written and signed log of its actions. 5. A summary of the actions required is shown at Figs 1 and 2.