Rank: Forum user
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Hi,
I have been asked to do a COSHH Assessment on concrete dust when drilling.
Does anyone have one that I could have a look at?
Thanks
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Rank: Super forum user
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Rank: Super forum user
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Rob
Include in your risk assessment the potential for cement burns due to cement dust on wet skin. Cement is notorious for causing skin burns.
Chris
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Rank: Super forum user
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Once it has set as concrete, it is no longer cement, so the hazards have changed.
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Rank: Super forum user
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Query: If I drill concrete using water (as is often the case), does the slurry contain liberated Calcium Hydroxide - i.e. is the slurry caustic?
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Rank: Super forum user
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Ray - I'm not sure.
Portland cement consists of a mixture of a compound of calcium oxide with alumina and two different compounds of calcium oxide with silica. In theory, no lime.
When mixed with water this mixture hydrates over a period of months. The three compounds take different times to react with water, which gives concrete a short, medium and long term hardening.The different types of cement (Portland, high alumina) differ in the proportions of the compounds and this has a big effect on the initial hardening time.
Is there any lime left? I don't know. Google Scholar may have something.
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Rank: Super forum user
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Judging by the practices observed around the UK wet cutting / drilling run off is generally not collected nor neutralised - seems a bit contradictory to wet down to protect the operative then leave the slurry to dry to dust and expose potentially more people to any hazards - CN3 refers to wet brushing / hosing down the area but no advice as to where.
http://www.hse.gov.uk/pubns/guidance/cn3.pdf
Quite a few fixings in to concrete (Re-bar / bolts etc..) use reactive chemical anchoring systems that may or may not involve additional hazards over and above the basic concrete mix (depends upon the formulation used) - in one construction site assessment the attached MSDS of the product carried a precautionary statement for sanding / drilling the cured chemical product due to potential Silica exposure.
Then there is the question of the aggregate used dependent upon the age of the material being drilled - quite a few horrors were buried in concrete in the days before enlightenment.
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Rank: Super forum user
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Judging by the practices observed around the UK wet cutting / drilling run off is generally not collected nor neutralised - seems a bit contradictory to wet down to protect the operative then leave the slurry to dry to dust and expose potentially more people to any hazards - CN3 refers to wet brushing / hosing down the area but no advice as to where.
http://www.hse.gov.uk/pubns/guidance/cn3.pdf
Quite a few fixings in to concrete (Re-bar / bolts etc..) use reactive chemical anchoring systems that may or may not involve additional hazards over and above the basic concrete mix (depends upon the formulation used) - in one construction site assessment the attached MSDS of the product carried a precautionary statement for sanding / drilling the cured chemical product due to potential Silica exposure.
Then there is the question of the aggregate used dependent upon the age of the material being drilled - quite a few horrors were buried in concrete in the days before enlightenment.
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