Summary – Numbers affected
It’s virtually impossible to know how many people are affected in the UK by CO, let alone CO+ (i.e. CO & /or other products of combustion – see https://www.co-gassafety.co.uk/about-co/other-toxins/) because of the lack of monitoring or testing for CO.
Impact – it’s likely that well over 3 million people in the UK are affected by CO at over 50 parts per million, way above WHO guidelines which is now 3.5 PPM averaged over 24 hours.
1.UCL Research.
Research commissioned from University College London published in an HSE press release dated 02.10.06 – click here – to inform its gas safety review highlights the dangers of CO poisoning in people’s homes and a lack of public awareness of the risks.
Early findings were:
* 23% of homes had 1 or more defective gas appliance;
* 8% of homes were judged to be at risk of dangerous levels of CO;
UCL’s report
This report, authored by Ben Croxford, found 50 of 270 homes (18%) had levels of CO exceeding WHO 8 hour average guidelines of 9 ppm.
Of this 50, 26 (9.4%) exceeded WHO 1 hour level (26ppm) & 10 (3.6%) exceeded WHO 30 minute guideline value of 52ppm.
Nearly 1 in 5 homes exceeded WHO 8 hour average guideline CO values of 9ppm, nearly 1 in 10 exceeded WHO 1 hour average guideline CO values of 26ppm and nearly 1 in 27 exceeded WHO 30 minute guideline CO values of 52ppm.
UK has 27.8 million households with an average household size of 2.4 = 66,720,000 people
8% of 66,720,000 = 5 337,600 so 5 million people.
- 45% of homes had received no information on CO dangers and
- A higher prevalence of problem appliances were in homes of vulnerable people – young, old & those in receipt of benefits.
The All-Party Parliamentary Carbon Monoxide Group (APPCOG) strongly supports including CO poisoning as a high risk. APPCOG’s inquiry ‘Preventing Carbon Monoxide Poisoning’, heard evidence CO poisoning causes 50 deaths a year, now revised to 40 in a report by the Cross Government Group on Gas Safety and Carbon Monoxide Awareness, 200 serious injuries & 4000 minor injuries – costing Department for Health in England & Wales approx £178m a year in medical & care costs, and creating immeasurable human suffering.
2. Research by John Moores University
Furthermore, it is thought the number affected by CO poisoning is considerably higher – a study conducted by Liverpool John Moores University in 2011 measuring CO levels in 109 homes over many weeks found:
- 24 homes had CO levels over 50 ppm – a level where symptoms of poisoning such as headaches, tiredness & drowsiness can be experienced.
- 53 homes had CO levels from 10 to 50 ppm – see link to:
‘Investigation of audible carbon monoxide alarm ownership’
https://www.emeraldinsight.com/doi/full/10.1108/SASBE-07-2013-0041 *
CO-Gas Safety states:- This article https://www.emeraldinsight.com/doi/full/10.1108/SASBE-07-2013-0041 * published in 2014 refers to the study done by John Moores Liverpool University in 2011-12 at 81.
*Note on how to access the article. When you click on this link, you will see a small button labelled ‘Reprints and Permissions’, next to the article date. That takes you to an online form to get a quote for reuse. It states that this is the licence only though, and that you still need to obtain the copy of the article from Emerald Publishing. A link I found for a preview of the first ten pages of the article (https://ur.booksc.eu/ireader/34239218) states to contact permissions@emeraldinsight.com CO-Gas Safety obtained a copy some years ago due to the kind permission of Emerald Insight.
‘Stage two fitted 173 homes with Lascar EL-USB data loggers. There were 109 properties in Liverpool with 73 homes in deprived areas and 36 in non-deprived areas. In Coventry 64 homes were targeted but these homes had not had a HFSC (Home and Fire Safety Checks) conducted. 40 were in deprived areas and 24 from non-deprived areas. The monitoring period ran from November 2011 until the following spring.
Homes equipped in Liverpool had been through the HFSC (Home and Fire Safety Check) in stage 1. However, homes that received a data logger in Coventry had not been assessed by a HFSC.
‘Approximately 29 per cent in Liverpool and 39 per cent of properties in Coventry had readings less than 10 Parts Per Million (PPM). According to WHO guidelines (see more about these further on) residents could stay in the property for eight hours before beginning to feel the effects of CO poisoning. In total 48 and 42 per cent of homes monitored in stage 2 in Liverpool and Coventry respectively had CO readings between 11 and 49 PPM; WHO guidelines recommend that residents would have between 30 and 60 minutes before they begin feeling the effects of CO. Lastly 22 percent and 18 per cent had dangerous readings of over 50 PPM, which would result in the effects of CO poisoning to manifest within 15 minutes of being indoors.’
It seems helpful to average the percentages of Liverpool & Coventry.
We refer to ‘In total 48 and 42 per cent of homes monitored in stage 2 in Liverpool and Coventry respectively had CO readings between 11 and 49 ppm;
WHO guidelines recommend residents would have from 30 to 60 minutes before feeling effects of CO.’
The average of 48 and 42% = 45% had CO readings from 11 to 49 PPM which according to WHO guidelines means residents would experience CO effects from 30 to 60 mins.
We refer to, ‘Lastly 22 percent and 18 per cent had dangerous readings of over 50 PPM, which would result in the effects of CO poisoning to manifest within 15 minutes of being indoors.
The average of 22% and 18% = 20% had CO readings over 50 PPM, which means residents would feel CO effects within 15 minutes of being indoors.
Note https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/families/bulletins/familiesandhouseholds/2020 In the UK there were 27.8 million households in 2020, resulting in an average household size of 2.4.
27.8 million times 2.4 = 66,720,000.
45% of 66,720,000 i.e. nearly 67 million people in UK = 30,024,000 so 30 million exposed to CO from 11 to 49 PPM for 8 hours.
20% of 66,720,000 = 13,344,000 i.e. over 13 million people in UK exposed to dangerous readings over 50 PPM, experiencing effect of CO poisoning manifest within 15 mins.
In total this means over 43 million people in the UK could be exposed to CO in levels far greater than recommended by WHO and significant numbers, running into millions, will eventually suffer chronic ill health from this exposure.
3. Promised further funded research on 75,000 homes in 2015
The research above was of huge concern but looked at relatively small numbers so a larger study was important. So the charity was delighted to read from this https://www.ljmu.ac.uk/about-us/news/life-saving-research-into-carbon-monoxide that this was planned.
‘The Gas Safety Trust (GST – now the Carbon Monoxide Research Trust – CORT) also awarded a grant to LJMU to expand the study from two city centres to five counties by partnering with five Fire and Rescue Services, Merseyside, Cornwall, Bedfordshire, West Midlands and Oxfordshire. The funding is also supported by an in-kind contribution from the Council for Gas Detection and Environmental Monitoring (CoGDEM) whose members have supplied CO alarms and data loggers to undertake a comprehensive CO investigation covering 75,000 households.’
That was years ago in 2015 – where is this research?
Stephanie Trotter brought this up at an APPCOG stakeholder meeting on 10.03.20 – The minutes reported progress was being made but it was not yet ready for publication. Considering the serious implications of existing small studies, we continued to lobby for this study to be finished and to be published.
CO-Gas Safety has since been told this study was not undertaken due to fire service cut-backs.
We are deeply disturbed this funding failure did not seem to be revealed until we questioned and pursued it. Surely, action should be taken now to remedy continuing trauma suffered by people who continue to be poisoned and /or cannot prove poisoning?
We have therefore lobbied and are continuing to lobby HSE, Ofgem and government etc. to insist the original recommendation made by HSC/E in 2000, that the gas emergency service should carry and use equipment to test gas appliances for CO, be implemented. We have been lobbying for this almost since we started in 1995 because within a few weeks or months it seemed obvious that with a deadly gas that could not be sensed using human senses and could kill in less than 2% in the air in under three minutes, that at least the gas emergency service should have a duty to test for CO whenever practicable. We now lobby for all Registered Gas Safe Engineers to have this duty too, before and after work is done on gas appliances. Before work is done, so those who may have been injured by CO, can inform their medics thereby saving NHS funds.After work is done so the engineer uses an objective test of his/her ability to make sure the appliance is left operating safely.
We are also lobbying for any CO found to be recorded and for the parts per million (PPM) of CO, where found, to be given in writing or digitally to those survivors and their families.
We are also lobbying and have done for many years, for all fuel engineers particularly domestic heating and cooking engineers to be registered as gas engineers are. Registration should also be extended to chimney sweeps.
In 2020 due to Covid we stated, ‘It seems from the research high levels of CO are widespread in the UK. Symptoms of CO are similar to those of any virus, including Covid-19. Therefore, the charity considers the gas emergency service should action testing of emissions of gas appliances for CO and for the air in the house or workplace, by autumn / winter 2021, especially as we had hoped this would have been done years ago!’
We have also lobbied for some research to be undertaken in 2000 homes which we learned would be statistically significant. Recently, we have renewed this request and suggested this in a question/comment at the CORT (The Carbon Monoxide Research Trust) Conference 2025.
WHO Global Air Quality Guidelines update 22.09.21
CO reduced to 3.5 PPM over 24 hours – this is now the new AQG level (Air Quality Guideline level).
BSI now even lower.
BS 40102-1:2023 includes for ‘acceptable’ CO:-
15 min: 35-100 mg/m3 versus WHO 100 mg/m3
1 hour: 10-35 mg/m3 versus WHO 35 mg/m3
8 hour: 4-10 mg/m3 versus WHO 10 mg/m3
24 hour: 2.3 – 4 mg/m3 versus WHO 4 mg/m3
History of WHO guidelines from 2010
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 https://apps.who.int/iris/bitstream/handle/10665/141496/9789241548885_eng.pdf?sequence=1 at page 12, which provides a table of mean concentrations over an average time of 10, 15, 30 minutes then 1, 8, 24 hours. This was published in 2014 but refers to WHO 2010.
|
Pollutant |
Mean concentration over averaging time |
||||||
|
|
10 min |
15 min |
30 min |
1 hour |
8 hours |
24 hours |
1 year |
|
CO (mg/m3) |
– |
100 |
|
35 |
10 |
7 |
– |
WHO 2010 (13)Using the Lenntech converter – https://www.lenntech.com/calculators/ppm/converter-parts-per-million.htm
7 mg/m3 equals 5.68 ppm (parts per million).
Guidelines see page 86 and also
The 24-hour guideline WHO Global Air Quality Guidelines update 22.09.21
‘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
[Note For those who want precise accuracy the limit is 4 mg/m3, which is 3.43ppm (conversion tool here: https://www.gastec.co.jp/en/technology/knowledge/concentration/) but we decided to quote 4 PPM to keep it simple. However, now the accepted level seems to be 3.5 PPM.]
Conclusion
CO+Savi (group of victims & victim groups) suggests the following statement(s) be used instead or with any existing numbers in presentations, press releases, publications, etc.
Short Version
“There is currently no conclusive and comprehensive way of accurately establishing actual number of people harmed to whatever level by CO and other toxins (CO+ for short).
It is recognised there are many sources of data collated over the years. However, it is scientifically inconclusive at this point in time.
We know some people suffer temporary illness, irreversible chronic ill health or death as a consequence of exposure to low-level, chronic and high-level, acute CO+ poisoning – Unfortunately, we do not know how many more are affected and have no way of objectively and responsibly estimating true figures.”
There is also a long version, which has not been finalised yet. When finalised, we will put it on our website.
This version has been so far agreed between Roland Wessling & CO-Gas Safety. We hope others will also support this.
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