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norac_170121
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    HSE published a load of exposure stats for asbestos cement work back in 2007. It can be obtained from the HSL archive – See HSL/2007/11  – aka HSL-711 which some may find useful and surprising, challenging the view that work with AC is almost always non-licensable (i.e. the Control Limit will not be exceeded and the works are SALI) . The following data is copied from Annex 1 of that document.

    11 ANNEX 1: MEASURED AIRBORNE FIBRE CONCENTRATIONS FROM
    WORK WITH ASBESTOS CEMENT.

    Table A1: Work on asbestos cement roofs personal exposure to asbestos

    Range Reference

    All work on ac roofing and sheets Not detected/<0.01 – 1.1 f/ml (from data below)

    Roof Repair “Representative” Not detected – 0.3 f/ml (CONSAD, 1990)
    Roof Removal “Representative” Not detected – 0.2 f/ml (CONSAD, 1990)
    Dry – replacing corrugated asbestos cement 0.01, <0.01 f/ml (Roberts, 1985)
    Collecting sheets and cleaning 0.24 f/ml (Roberts, 1985)
    Removal of corrugated sheets (detachment and sliding to gutter)
    0.047 f/ml (Preat, 1993)
    Throwing sheets into lorry 0.161 f/ml (Preat, 1993)
    Removal of corrugated sheets (detachment, stacking on elevator, placing in pallets)
    0.028, 0.038 f/ml (Preat, 1993)
    Removal of corrugated sheets (detachment) 0.018 f/ml (Preat, 1993)
    Stacking of sheets of pallets 0.032 f/ml (Preat, 1993)
    Removal of slates (detached with hammer) 0.064 f/ml (Preat, 1993)
    Sliding slates to gutter; throwing to ground 0.195 f/ml (Preat, 1993)
    Removal of slates (detachment and stacking) 0.037, 0.044 f/ml (Preat, 1993)
    Removal of slates (detachment and placing in container on roof)
    0.050, 0.176 f/ml (Preat, 1993)
    Removal of slates (pulling off, stacking on elevator, broken slates thrown to ground)
    0.100, 0.122 f/ml (Preat, 1993)
    Removal of slates (detachment with hammer, sliding to gutter)
    0.068 f/ml (Preat, 1993)
    Bringing slates down and throwing into container
    0.056 f/ml (Preat, 1993)
    Wet (but not effective) Mean 0.020 f/ml (Lange & Thomulka,
    2000)

    Roof Replacement
    Dry replacement (severely weathered) – unfastening, removal, stacking, disposal, installation of new
    roofing 0.03 – 0.24 f/ml (Brown, 1987)
    Dry unfastening, removal, disposal, installation of new roofing (no stacking)
    0.03, 0.03 f/ml (Brown, 1987)
    Dry replacement (severely weathered) 0.04 – 0.27 f/ml (Brown, 1987)
    Dry removal (painted) 0.07 – 0.32 f/ml (Brown, 1987)
    Wet removal (painted) and replacement (careful handling and wetting as stacked)
    Not detected – 0.07 f/ml (Brown, 1987)
    Replacement (severely weathered) after lignin sulphonate treatment
    0.23 f/ml (Brown, 1987)
    Replacement (severely weathered) after sealing with acrylic resin
    0.03 – 0.08 f/ml (Brown, 1987)
    Replacement (severely weathered) after sealing with acrylic resin
    0.04 – 0.26 f/ml (Brown, 1987)

    Roof Removal – Demolition
    Dry (building collapsed) 0.10 – 0.47 f/ml (Brown, 1987)
    Dry (from scissors lift) 0.04 – 0.12 f/ml (Brown, 1987)
    Sheets stacked in confined space 0.30 – 0.53 f/ml (Brown, 1987)

    Sheets stacked in confined space (accumulated dust under laps and ridges)
    0.34 – 1.1 f/ml (Brown, 1987)

    Wet 0.05 – 0.06 f/ml (Brown, 1987)
    Wet (sheets staked in confined space) 0.10 – 0.13 f/ml (Brown, 1987)
    Wet (sheets staked in confined space; accumulated dust under laps and ridges)
    0.29 – 0.68 f/ml (Brown, 1987)

    Sealed with acrylic resin 0.11 – 0.32 f/ml (Brown, 1987)
    Sealed with acrylic resin (sheets stacked in confined space; accumulated dust under laps and ridges)
    0.41 – 0.76 f/ml (Brown, 1987)

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