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The HSE in England advise in the FAQ section of their website here "Many cases of inadvertent, short-term exposure to asbestos will most likely have led to minimal exposure to fibres, with little likelihood of any long-term ill health effects" and yet their Leaflet EM1 (same source) warns, on discovering damaged asbestos, to stop work immediately and get everyone out of the room. Further advice states that only asbestos in good condition is safe (implying that all asbestos which is damaged is not).

Following this logic, if I were to inadvertently damage an asbestos ceiling tile, there would be little likelihood of any long-term ill health effects, but if someone else damaged it and I discovered the damage, it would become a danger in need of immediate evacuation and remedial action. These two statements seem contradictory.

Furthermore, this source here suggests that anything other than loose insulation and AIB produces less than 0.1 fibres/ml even when worked on, much less when damaged. Exposures to this level even for a week two would give yearly exposure of less than 0.003f/ml.y. This source here gives risks from these levels lower than 1:100,000.

The HSE list 1:100,000 as the guideline for acceptable risk (HSE 1999). So are the HSE over stepping their own risk guidelines when suggesting any emergency action needs to be taken on discovering anything other than loose asbestos and severely damaged AIB?

For clarity - The HSE, by their own standards, only include action to reduce risks to health which are greater than 1:100,000 (HSE 1999). Inclusion of advice (especially mandatory advice) in their publications therefore carries an implicit claim that the un-mitigated activity carries a risk to health greater than 1:100,000. Their advice to "evacuate the room" on the discovery of any damaged asbestos, and that all damaged asbestos is unsafe, implies that the risk to health from all damaged asbestos over short periods of time is greater than 1:100,000. The evidence I've been able to source seems to suggest that this figure would only be the case for very specific asbestos applications and damage types, hence my question here.

Pseudonym
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    ... sorry, what's the notable claim that you want to refute? AFAIK this site is *not* about nitpicking guidelines of various entities. – Bakuriu Nov 03 '16 at 08:06
  • @Bakuriu The claim is that *any* exposure to asbestos containing materials (other than AIB and loose fill) even for short periods of a few days entails a risk greater than 1:100,000 of damage to health. The claim is implicit in the guidelines "evacuate the room" and is certainly "notable", even infamous, but I cannot find evidence to substantiate it. If that's not what this site is for, then I must have misread the help pages and I apologize. – Pseudonym Nov 03 '16 at 10:22
  • To put it the other way round, I can only find evidence to substantiate a claim that damaged AIB or loose fill asbestos could produce a risk to health of greater than 1:100,000 (1:5,000 according to the Darton source) after a few hours of exposure, but that is not the claim the HSE are making, they are claiming that any damage to *any* asbestos creates a risk greater than their 1:100,000 threshold for action to be taken. – Pseudonym Nov 03 '16 at 10:27
  • [Here](http://skeptics.stackexchange.com/questions/35067/are-activities-in-which-both-people-bleed-on-each-other-considered-no-risk-for?rq=1) is a highly voted question asking the same thing (about risk) for HIV so surely this should fit the site? I've edited my question to make the claim easier to identify. – Pseudonym Nov 03 '16 at 10:32
  • I agree with @Bakuriu: you seem to be nitpicking in quite a petty manner. The guideline is in place. Whether you think it is too harsh or contradictory is of little to no relevance because I **assume** you would not be so foolish as to ignore HSE guidelines based on any answer you get on StackExchange. If you want to get annoyed about harsh guidelines, start looking at guidelines regarding **radiation** and you will find some true stupidity there. But this.... it is a complete non-issue. –  Nov 03 '16 at 11:13
  • @Michael I'm not sure if it's something about the tone, if so it's unintentional, but I don't understand where the "nitpicking" and "advice" issues arise from. I have no asbestos issue and am not planning on taking or not taking HSE advice, my question has nothing whatsoever to do with their advice, I'm interested in their **claim** about the risks, that and only that. Is there any evidence to substantiate the claim that all (or even most) asbestos exposure even for short durations carries a risk to health greater than 1:100,000? that's really all there is to it, the rest is just context. – Pseudonym Nov 03 '16 at 11:40
  • @Pseudonym Did you read through the "Research and reports" section on the very webpage you are linking from? –  Nov 03 '16 at 11:49
  • @Michael Yes, that's where I got both my sources from, but, as I mention in the question, they both seem to produce figures much lower than 1:100,000. The Darton (2000) paper for example specifically states that it has not even produced risk estimates for such low fibre exposure specifically because it would be below the HSE threshold (p.20) – Pseudonym Nov 03 '16 at 12:03
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    @Pseudonym If your claim is about the risk then please remove all references to guidelines which are irrelevant and define what a risk of "1:100000" means so that we may be able to find some scientific article that proves or disproves that level of risk. – Bakuriu Nov 03 '16 at 12:30
  • @Bakuriu I'd like to do whatever is necessary to make the question work, but it's the appearance in the published advice that constitutes the claim. The HSE state that they will *only* advise action on threats greater than 1:100,000, so it is the fact that the advice is published which constitutes the claim. I'm not sure how I could deal with that without mentioning the advice, but any ideas would be welcome. – Pseudonym Nov 03 '16 at 12:59
  • If it's simpler to avoid my arithmetic on fibre concentrations, the studies [here](https://www.ncbi.nlm.nih.gov/pubmed/2298180) and [here](https://www.ncbi.nlm.nih.gov/pubmed/1410659) both conclude that buildings have too low a concentration of fibres to significantly increase health risks "irrespective of the condition of the material in the buildings". I could put these studies in the question instead of my calculations if it helps. – Pseudonym Nov 03 '16 at 13:02

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You seem to be getting hung-up on the true risk of any given exposure incident, where as the document you cite are not necessary discussing the true risk of any given event. It is a rule of thumb.

... if I were to inadvertently damage an asbestos ceiling tile, there would be little likelihood of any long-term ill health effects...

This is entirely in line with evidence you cite, assuming you take remedial action to contain or remove the broken ceiling tile, stopping your exposure.

... but if someone else damaged it and I discovered the damage, it would become a danger in need of immediate evacuation and remedial action.

Discovering damaged asbestos implies that you don't know the length of exposure, which is an important factor in determining the absolute risk of exposure. Finding damaged boiler insulation in a occupied area could mean that the occupants have been exposed for less than 5 minutes or 40 years.

You have misquoted EM1 for unlicensed work. "...on discovering damaged materials that may contain asbestos, to stop work immediately and get everyone out of the room." Unless you have familiarity of with asbestos products, it may not be in your ability to determine the level of exposure: type of asbestos or the friable nature of the material. It would be prudent to follow the guidelines to limit exposure until the material is identified.

Their advice to "evacuate the room" on the discovery of any damaged asbestos, and that all damaged asbestos is unsafe, implies that the risk to health from all damaged asbestos over short periods of time is greater than 1:100,000.

...would only be the case for very specific asbestos applications and damage types...

Again, if the asbestos is discovered we still don't know if the exposure was short-term, or if the material is not known, exposure levels could be extremely high. Possibly increasing the risk beyond acceptable limits for occupants. Asking the occupants to leave the structure until experts examine the situation would not be unreasonable, but best practice.

...that all damaged asbestos is unsafe...

Though I couldn't find explicit phrasing to agree, the CDC notes, "recommends that exposures be reduced to the lowest feasible concentration". Implying that there may be no safe level of exposure, but they do set a maximum level that is the same as HSE's limit. Fibres may remain in the body indefinitely and can accumulate increasing the risk of scarring and cancer.

Though everyday, realistic, exposure risk may not fall above their standard. The perceived risk from general public may prompt the HSE to publish statements. "The squeaky wheel gets the grease."

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RomaH
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    Thank you for taking the time to respond. a couple of points. Firstly, I wish I could have made this clearer in the question, but I'm not questioning the HSE's advice, I think it is perfectly reasonable, what annoys me is when advice is given *without* re-assurance of the actual risk involved. This tends to lead to the public to a completely confused attitude to risk which I believe contributes to the poor lifestyle choices which burden our healthcare systems. People see the risks they are told to mitigate as high those that go un-legislated they see as low. – Pseudonym Nov 06 '16 at 07:37
  • As such, what matters is not whether the HSE advise you evacuate the room, but whether they mention that, should the material turn out to be Chrysotile, or in a bonded matrix, your chances of any health effects from small to medium damage are probably comparable to the car journey you took to evacuate the building, or the burger you ate whilst out, or the cigarette you smoked out of nerves. I just believe that people who identify a risk have a duty to put that risk into context. As you so rightly say "the squeaky wheel gets the grease", risks should always be put in context. – Pseudonym Nov 06 '16 at 07:45
  • Secondly, maybe a separate question for skeptics, there definitely is a lower "safe" limit of exposure and this is consistently mis-reported. This paper [here](http://www.medscape.com/viewarticle/422880) shows the average healthy lung has about a million asbestos fibres in it, scientists *do not know* what exposure levels might lead to these quantities and hence cannot *set* a lower limit, but there definitely is one, by the standards we normally use in life for other things (alcohol, fast food, urban air pollution etc.) – Pseudonym Nov 06 '16 at 08:00