Rank: New forum user 
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Hello,
We recently had a licenced contractor remove some asbestos bitumen mastic from a floor. They used a concrete scabbler to do so. However I was rather concerned to find that they did not feel the need to use an exclosure, negative pressure or air extraction. The rather large dust cloud was just vented out of the window and the remainder (H-class) vacuumed. There was a rather ineffectual plastic sheet over the door.
The contractor explained that the fibres are held firmly in the bitumen and so are unlikely to be released and the dust was concrete. I spoke to the HSE and they pretty much echoed this. However, being curious (and concerned - this was a child's bedroom) I asked for further clarification on this (has this actually been experimentally confirmed?) However the HSE came back with the (frustrating and slightly circular, but understandable) argument that as this was a low risk activity they cannot expend limited resources on explaining to me any further why it was low risk.
So, I'm opening it to the forum: have any published experimental measurements been taken of using a scabbler on asbestos bitumen mastic (Google is failing me)? What sort of fibre release is expected? Is this actually a standard practice in asbestos removal - i.e. a standard scabbler without air containment? This seems to go strongly against HSE guidance A37 for removing asbestos-containing mastic which clearly says "Caution Do Not Use Power Tools".
Any further insights welcome.
Thank You!
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Rank: Super forum user 
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I note there is no mention of an air clearance certificate, which is a little surprising. This is the only way one can be sure asbestos fibres do not remain in the atmosphere post asbestos removal works. This certificate may not be required for low-risk asbestos removal. However, it does give confidence there are no residual fibres causing a hazardous environment.
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Rank: New forum user
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Yes - should have mentioned - an air clearance test was done and came back satisfactory. However, because of the high level of concrete dust in the air it wasn't possible to do the test immediately after the scabbling finished so it was started about 45-60 minutes later (by which time some settling would presumably have happened).
I guess the clearance certificate alone was not giving the level of reassurance I wanted so was really wanting to confirm if scabbling has been tested as a low risk removal method and was widely practiced.
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Rank: Super forum user
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In that case I don't think there is anything to be concerned with.
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Rank: New forum user
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I guess what I'm saying -in the general case - is that I don't understand the conflict between HSE A37 saying "Caution Do Not Use Power Tools" and then also saying the scabbling activity was low risk. A scabbler is very much a power tool - did we just get lucky in the air test, or is the warning wrong and this is actually a generally acceptable and low risk method?
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Rank: Forum user
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This guidance is issued by the Health and Safety Executive. Following the guidance is not compulsory, unless specifically stated, and you are free to take other action.
The above is from Page 2 of A37
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Rank: Super forum user 
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What did their method statement suggest? Did they use any kind of fibre suppressant? Bitumen removal doesn't need to be undertaken under fully controlled (Full enclosure, analyticals etc) conditions or require notification to the HSE/ LA, but the controls should be suitable. Bitumen isn't a material that is very friable compared to something like pipe lagging or AIB. By the sounds of it they possibly undertook an environmental clean of the area if they H-Vac'd. Did you receive a reoccupation certificate and waste transfer note from the contractor? I would recommend that you speak to the removals contractor or your asbestos surveyor/ analyst who undertook your air testing to get a better steer in this siutation.
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Rank: New forum user
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Originally Posted by: James Robinson  This guidance is issued by the Health and Safety Executive. Following the guidance is not compulsory, unless specifically stated, and you are free to take other action.
The above is from Page 2 of A37
Thanks - I hadn't looked at the smallprint. However, surely either power tools should not be used (if they have been shown to be dangerous) or else (if shown otherwise) there should not be a caution against them as unnecessary warnings will devalue any advice given on anything. As a non-specialist this causes confusion and anxiety, especially if a contractor does something that the HSE says in big red writing not to do, even if “not compulsory”.
But going back to the original question – other than the case of my own air test of course, has scabbling of asbestos bitumen actually been demonstrated (in a controlled experimental) to result in negligible fibre release? And is it a widely used practice?
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Rank: Super forum user
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As a non-specialist this causes confusion and anxiety, especially if a contractor does something that the HSE says in big red writing not to do, even if “not compulsory”.
Could I suggest you speak to your surveying company or the contractor and ask them to clarify for you. It may possibly be that the scabbler allows alot less time on site rather than 1 or 2 men spending days breaking it out by hand if it is across the entirity of the room. Consultancies that provide analytical works will often undertake method statment approvals, desk top studies of works and query things directly with the removal contractor before approving on request. If you are unsure of what the method statement is saying, step back and get competent advice before the removals contractor steps foot on site. You may want to consider perhaps attending a course in managing asbestos if this is going to be part of your day to day work? It was a huge help for me when I was first starting assisting in the asbestos management side of things.
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Rank: New forum user
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Originally Posted by: jodieclark1510 Could I suggest you speak to your surveying company or the contractor and ask them to clarify for you. It may possibly be that the scabbler allows alot less time on site rather than 1 or 2 men spending days breaking it out by hand if it is across the entirity of the room. Consultancies that provide analytical works will often undertake method statment approvals, desk top studies of works and query things directly with the removal contractor before approving on request. If you are unsure of what the method statement is saying, step back and get competent advice before the removals contractor steps foot on site. You may want to consider perhaps attending a course in managing asbestos if this is going to be part of your day to day work? It was a huge help for me when I was first starting assisting in the asbestos management side of things.
Yes, the contractor said that scabbling was the efficient way to remove the bitumen as very little fibres would be released (due to the bonding nature of the material and low asbestos content) and a full environmental clean would be done (which it was), followed by an air test.
The analyst did not express any concerns regarding the method.
I only latterly encountered the HSE guidance note about the use of power tools, hence looking for independent reassurance by people who are familiar with this sort of work that the method is normal practice for bitumen.
(I don't personally expect to have to deal with asbestos removal again - this was a one-off situation).
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Rank: Super forum user
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Sometimes it pays to speak to the contractor/ consultant because its not always a black and white situation like it appears in the gidance docs etc. Speaking to those in the field can be a huge help, I've learned that as I've become more involved in the asbestos management/ removal side of things in my role.
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