1. www.arbounie.nl Exposure to solvents in the metal fabrication and engineering industry 2nd European Conference on AWARE and other coding systems, Gent, October 4 & 5, 2007 Henri Heussen, PhD, & Hester Dekker, MSc

2. Background 1. Web based tool metal sector: coating & degreasing 2. Aim: exposure to solvents self risk assessment by SME’s and larger companies Tool: two validated routes  Good Practices (Risk Management Measures = RMM)  Model: Occupational Air Requirement (OAR) or Required Air Quantity (RAQ) This part: validation of good practices and applied ventilation model Next part IVAM: using the same exposure data > validation of AWARE ventilation model

3. Activities studied Good Practices  Degreasing by dipping – (semi) closed system  Mixing paint – closed mixer  Cleaning spray guns – closed washing machine with LEV Model  Brushing/rolling  Spraying

4. Model: calculation OAR Legenda: OAR:Occupational Air Requirement (m 3 /l) Vi:Volume solvent/liter paint (ml/l) i:index including all solvents in the paint ρi:specific gravity (g/ml) fi:evaporation factor (default 1) OELi:Occupational Exposure Limit solvent (mg/m3) or hardener & thinner

5. Calulation needed ventilation Q OAR : Ventilation needed according to OAR (m 3 /hr) OAR:Occupational Air Requirement (m 3 /l) Ve:Amount used (l) T:Time (hr)

6. Calculation Exposure Index (EI) Legenda: EI model :Exposure index Q OAR : Needed ventilation (m 3 /hr) Q d :Actual ventilation (m 3 /hr)

7. Results - Good Practice degreasing: (semi) closed system 5 companies 20 measurem. EI RMM

8. Results - Good Practice mixing paint: closed mixer 10 comp. 32 meas. EI RMM

9. Results - Good Practice cleaning spray guns: closed washing machine with LEV 10 comp. 34 meas. EI RMM

10. Conclusions Good Practices:  Predefined Good Practices are indeed good (statistically validated)  Also other Good Practices found (some statistically validated)  Detailed description of Good Practice is necessary and a prerequisite for correct use of the tool

11. Results brushing/rolling (excluding natural ventilation) 7 companies 20 measurem. EI model EI measurements

12. Results spraying (excluding natural ventilation) 6 companies 14 measurem. EI model EI measurements

13. Conclusions model  Very good correlation between model and measurement data  However, model does not always overestimate  Therefore for brushing/rolling a safety factor is needed!  For spraying not a priori necessary > political decision  To be calculated on the basis of sensitivity/specificity

14. Conclusions model (continued)  After adding safey factor(s) model = validated exposure assessment tool  Erring to the side of caution:  separation between local and general ventilation  MSDS upper limit range (volume solvent/l)  more than one sprayer in the same room > total amount of solvents used by all sprayers attributed to one sprayer  Covers a wide range:  in amount of paint used per time  room volume  type of ventilation  ventilation capacity  measured exposure index

15. Thanks for your attention! This study: - performed by order of the social partners (FME-CWM, Metaalunie, FNV, CNV, De Unie) - supported by the Ministry of SZW (VASt programme)

16. Conclusions model  Very good correlation between model and measurement data  However, model does not always overestimate  Therefore for brushing/rolling a safety factor is needed!  For spraying not a priori necessary > political decision  To be calculated on the basis of sensitivity/specificity ActivitySensitivitySpecificity Spraying80%75% Brushing/rolling43%83%

17. Materials & Methods Good practices  Personal air sampling, task based  Duration: minimum 5 minutes  NIOSH sampling tubes (100/50mg), flow 200 ml/min  Per activity, max. 3 measurements per company per person  Lab analysis: ~ 250 solvents  Exclusion:  no regular maintenance  other sources with solvents nearby  other activities with solvents  enclosed space  outside Also: measurements under non-good practice conditions Grouped separately: stoffenmanager.nl model

18. Materials & Methods Good practices (continued)  Collection of determinants of exposure: Duration of measurement Control measures near field Control measures far field Room volume & ventilation capacity Composition of used products (MSDS)  Calculation of Exposure index  Compliance statistics (SAS Windows, version 8.2: lognormality, GM, GSD, 95% confidence interval, noncompliance probability

19. Materials & Methods Model  Personal air sampling, task based  Duration: minimum 1 hr brushing/rolling & 20 min. spraying  NIOSH sampling tubes (100/50mg), flow 50-200 ml/min  Per activity, max. 3 measurements per company per person  Lab analysis: ~ 250 solvents  Exclusion:  no regular maintenance  other sources with solvents nearby  other activities with solvents  enclosed space  outside

20. Materials & Methods Model (continued)  Collection of determinants of exposure: All info needed for model calculations Composition of used products (MSDS)  Calculation of Exposure Index  Correlation statistics model – measurement data: Pearson, both untransformed & lognormally transformed data