Community Air Pollution from Crash Repair Workshops

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					Community Air Pollution from
  Crash Repair Workshops

          Dino Pisaniello
       Department of Public Health
      Adelaide University, Australia
 Background to the public health issue

 Aims and objectives of study

 Project design

 Proximity data

 Stack emission and ground level data

 Implications
components of

Associated with
Community concerns about emissions
from spray painting workshops
– odours, potential toxic effects etc.

Australia has one of the highest rates of

How significant is the issue?

 To identify all crash repair spray painting
  workshops in the Adelaide metropolitan
  area which use (two-pack) isocyanate

 To determine and characterise, using
  descriptive statistics, the proximity of
  exhaust stacks to homes and offices.
             Objectives (cont.)
   To quantitatively determine, for a sample of

       stack emissions of isocyanates and solvent vapours,
        with concurrent measurement of meteorological

       ground level concentrations of isocyanates and solvent
        vapours at various distances from the emission source

   To interpret the public health significance of the
    data by comparison with occupational and
    environmental air quality guidelines.
                       Offices   (n)   %
                        <10m      5    4
Proximity Data          <25m     14    11
                        <50m     43    33
                        none     88    67
n = 131
                       Houses    (n)   %
Other = other small     <10m     13    10
business, factories,    <25m     38    29
shops etc.              <50m     71    54
                        none     60    46

                       Other     (n)   %
                       <10m       22   17
                       <25m       91   69
                       <50m      122   93
                       none       9    7
Isocyanates            (HDI and HDI oligomers)

    • using coated glass fibre filters and HPLC UV/EC
    • isokinetic stack sampling

Solvent vapours
(toluene, xylenes, butyl acetate and MEK)
    • charcoal sorbent tubes with GC/FID analysis

Meteorological variables
(wind speed, direction, temperature, humidity)
    • MEA automatic weather station positioned on roof

 Isocyanate spray time is relatively short (2-15% of day)
 Some touch up painting work (usually non-two pack) done
  outside of booth
 There appears to be adequate plume dispersion – the
  plume is seen to rise and disperse
 Workshops rarely use HVLP guns
 Charcoal filters noted for one workshop
                                                   ISOCYANATE CONCENTRATION
                                      Time (min)    (mg NCO/m3)  (mg NCO/m3)
Stack                                                   TWA     during spraying
                  WORKSHOP 1

Isocyanate             Day 1             405            3.0           77
                       Day 2             341            1.4           42

Data              WORKSHOP 2

                       Day 1             339            17            890
                       Day 2             436            11            645

                  WORKSHOP 3
Overall median
= 136 mg NCO/m3        Day 1             334            13            201
                       Day 2             315            11            152
during spraying
                  WORKSHOP 4 (charcoal filter on emissions)

and                    Day 1             362            0.6           13
                       Day 2             260            0.4            8
= 11 mg NCO/m3
                  WORKSHOP 5
as a daily TWA
                       Day 1             361            19            119
                       Day 2             275            66            502
Stack Solvent Concentrations During Spraying

                 Median   Geometric    Range
                 mg/m3      mean       mg/m3
 Toluene          25         28        3 - 630
 Xylene           52         43        3 - 402
 Butyl acetate    70         44       0.3 - 523
 MEK              2.6        1.2       0.1-12
Interpretation – Stack Monitoring

Data show isocyanate concentrations to be several times the
STEL while spraying is in progress
i.e. 70 mg NCO/m3
Will depend on the proportion of hardener, isocyanate
content of hardener, gun type, shape and orientation of
object being sprayed, booth exhaust filtration efficiency etc.

Total solvent concentrations while spraying:
100 - 1,000 mg/m3
These values approximate STELs
Perimeter Samples

Isocyanates       (HDI and HDI oligomers)

Below the limit of detection
(approx. 0.05 mg NCO/m3)

Solvent vapours
Below the limit of detection
(approx. 0.1 mg/m3) except for one sample
where work was done outside of booth
[3.6 mg/m3 for toluene]
   Isocyanate emissions are at hazardous concentrations near the
    stack when spraying is occurring. However, isocyanate spray time
    is relatively short (2-15% of day)
   Ground level (perimeter) concentrations are very low
   There appears to be adequate plume dispersion – the plume is
    seen to rise and disperse
   Solvent vapour concentrations at the stack are at marginally-
    hazardous levels
   Solvent vapours at ground level are very low, but there may be an
    odour depending on wind direction
   Work outside the booth may generate nuisance levels of solvent
   The lowest concentration of isocyanates and solvents were found
    for a booth with a charcoal filter

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