Numbers affected by CO+

See WHO guidelines for indoor air quality: selected pollutants 15.12.10

ISBN 978 92 890 0213 4

See page 70 second para from the bottom.

Walker (130) states that the incidence of chronic carbon monoxide exposure

in Great Britain is officially 200 per year, while at the same time “250 000 gas appliances

are condemned annually”. He speculates that if only 10% of these appliances

give off significant amounts of carbon monoxide that reach the breathing

space of residents, as many as 25,000 people every year may be exposed to carbon

monoxide in their homes. The carbon monoxide support study (89) found that

“only one case out of 77 was correctly identified (i.e. diagnosed) on the basis of

symptoms alone” and that medical professionals were the least likely group to

“discover” the fact of the carbon monoxide poisoning.

See also page 86


The 24-hour guideline

Chronic carbon monoxide exposure is different from acute exposure in several

important respects, as noted above. Thus, a separate guideline is needed to address

minimal exposure over 24 hours, rather than the 8-hour period used in

the acute guidelines. The latest studies available to us in 2009, especially those

epidemiological studies using very large databases and thus producing extremely

high-resolution findings, suggest that the appropriate level for carbon monoxide

in order to minimize health effects must be positioned below the 8-hour guideline

of 10.5 mg/m3, possibly as low as 4.6–5.8 mg/m3. This is also essential since

the minimal exposure time for this guideline is three times longer.

‘Note to explain these levels

10.5 mg/m3 = 8.9 Parts Per Million so call it 9 PPM

4.6 mg/m3 = about 4 PPM

Extract first published in our press pack 2014 pages 6 & 7

Research commissioned from University College London, published in a press release dated 02.10.06 by HSE (click here), to inform its gas safety review highlights the dangers of CO poisoning in people’s homes, coupled with a lack of public awareness of the risks.

The early findings of the research include:

  • 23% of homes had one or more defective gas appliance;
  • 8% of homes were judged to be at risk of dangerous levels of CO;

Note If there are 22 million households (please see 2011-12 English Housing Survey ( with 2.3 people in each household, there are therefore 50,600,000 people and 8% of them are 4,048,000. Call this 4 million people – be conservative and call it 3-4 million in the UK.

  • 45% of homes had received no information on the dangers of CO; and
  • A higher prevalence of problem appliances was found in the homes of vulnerable people (young, old, those in receipt of benefits).

Further research with similar findings has been undertaken by John Moore’s university 2012. More than 27,000 properties were visited.

The All-Party Parliamentary Carbon Monoxide Group strongly supports the inclusion of carbon monoxide poisoning as a high risk. The All-Party Parliamentary Carbon Monoxide Group’s recent inquiry, ‘Preventing Carbon Monoxide Poisoning’, heard evidence that carbon monoxide poisoning causes 50 deaths a year (revised to 40 in the latest report by the Cross Government Group on Gas Safety and Carbon Monoxide Awareness), 200 serious injuries, and 4000 minor injuries – which costs the Department for Health in England and Wales approximately £178m a year in medical and care costs, as well as creating immeasurable human suffering.

Furthermore, it is thought that the number affected by CO poisoning is considerably higher– a recent study conducted by Liverpool John Moores University in 2011 measured CO levels in 109 homes over a number of weeks: it found that 24 homes had CO levels greater than 50 ppm (parts per million) – a level in which symptoms of poisoning, such as headaches, tiredness, and drowsiness can be experienced. A further 53 homes contained CO levels between 10 and 50 ppm.

CO-Gas Safety states:-

This then shows about 22% of homes with CO levels exceeding 50 ppm and 49% of homes with CO levels between 10-50 ppm. This equates very well with other research done over the last 10 years. If one was to extrapolate these figures across the whole of the UK, then we would arrive at a number close to 15 million UK citizens being poisoned by CO in levels greater than 50 ppm and around 34 million being poisoned by levels  between 10 and 50 ppm. In total this is 49 million people in the UK being exposed to CO in levels greater than those recommended by the World Health Organisation and as a consequence significant numbers, running into millions will as a result of this exposure eventually suffer chronic ill health.

How do CO and other Toxins impact on the UK Population?

CO+Savi (group of victims and victim groups) suggests that the following statement(s) is/are being used instead or at least in conjunction with any existing numbers in presentations, press releases, publications, etc.

Short Version

There is currently no conclusive and comprehensive way of accurately establishing the actual number of people harmed to whatever level by carbon monoxide and other toxins (CO+ for  short).

It is recognised that there are many sources of data collated over the years. However, this data is scientifically inconclusive at this point in time. We know that some people can suffer temporary illness, irreversible chronic ill health or death as a consequence of exposure to either low-level,chronic and high-level, acute CO+ poisoning. Unfortunately, we do not know how many more areaffected and we have no way of objectively and responsibly estimating the true figures.

There is also a long version which has not quite been finalised yet. When it has been finalised, we will put it on our website.

This longer version has been agreed so far between Roland Wessling and CO-Gas Safety. We hope that others will also support this.

Longer Version

Carbon monoxide and other Toxins (CO+ for short) are a by-product from burning fossil fuels as well as alternative, comparable fuels created synthetically or from renewable sources. Depending on the type and the amount of fuel burned, the effectiveness of the exhaust system, such as chimneys or extraction flues, and the quality of the burning process itself, there can be high or low quantities of CO+ produced. CO+ can harm us in different ways. It can kill in minutes through high concentration (acute poisoning), while at the other end of the spectrum, CO+ can cause illness or death slowly through low concentrations (chronic poisoning). In both cases, the general health of individuals and potential, underlying conditions may influence the impact.

In order to quantify the impact that CO+ has on a population, it needs to be recorded and the recorded data analysed. In order for it to be recorded, there need to be methods of measuring and detecting the impact of CO+ as well as a systematic application of these methods. It is recognised that there are many sources of data collated over the years, but, this data is scientifically inconclusive at this point in time. However, this data only represents one section of the true impact and we currently do not know what percentage of the true impact the existing data represents. There is currently no conclusive and comprehensive way of accurately establishing the true number of people harmed to whatever level by CO+. In other words, any existing numbers of deaths or injuries caused by CO+, only represent a currently unknown percentage of the true impact on the population.

While any activity on gathering data is positive, helpful and important, it should not inadvertently lead to the misunderstanding that any such numbers represent the true impact of CO+. And because we simply do not know how many people are currently suffering from the impact of CO+, we suggest that this statement is being used instead or at least in conjunction with any existing numbers in presentations, press releases, publications, etc.

The burning of fossil fuels and the inevitable production of CO+ is going to be part of our lives for the foreseeable future. We all benefit from the warmth, electricity and transport it creates. This makes it even more important that we handle the information about the impact of CO+ on the UK population objectively, responsibly and carefully. This statement is not designed to be alarmist. It simply promotes an honest, respectful and responsible way of informing the public about the true impact of CO+ on their lives until we have a comprehensive and conclusive way of measuring, recording and analysing data that will represent the true impact of CO+.