Air Emissions from Autobody Repair Activities

1. Air Emissions from Autobody Repair Activities • Two basic kinds of air emmissions • Volatile Organic Compounds (VOCs) • Particulate (solids) • Volatile Organic Compounds (VOCs) • Volatile means the compounds “evaporate rapidly at a low air temperature”. • VOCs are chemicals, such as paint thinner, that evaporate rapidly Collision Repair - Reducing Air Emissions 12-1 (a)

2. Air Emissions from Autobody Repair Activities • VOCs contribute to the formation of smog in the lower atmosphere. • Material Safety Data Sheet will indicate a product’s VOC content. • Particulate • Solid part of paint • Contains the binder, pigments, and other additives. Collision Repair - Reducing Air Emissions 12-1 (a)

3. Air Emissions from Autobody Repair Activities • Some paint particulates are easy to see in the air, while others are not. • Nonetheless, all particulates decrease the air quality of our environment. Collision Repair - Reducing Air Emissions 12-1 (a)

4. Factors Affecting Air Emissions • Paint Booths • Paint booths control particulates • If equipped with paint arrestors (exhaust filters) • If used with a ventilation system • Can filter incoming air and remove dust that can ruin a finish. • Transfer Efficiency • Improved transfer efficiency • Less paint waste Collision Repair - Reducing Air Emissions 12-2 (a)

5. Factors Affecting Air Emissions • Less overspray • Lower air emissions. • Improve spraying techniques • Using equipment that is capable of a higher transfer efficiency. • Closed Solvent Storage Containers • Reduce evaporation • Keep used solvent-soaked rags in closed fire-proof waste container. Collision Repair - Reducing Air Emissions 12-2 (b)

6. Factors Affecting Air Emissions • Sanding/Blasting • Dust is potentially hazardous because it is contaminated with paint. • Use portable sandblasters with a vacuum attachment. • Keeps the air in the shop cleaner. • Worker exposure to dust reduced • Less dust reaches the outdoor air where it can cause pollution problems. Collision Repair - Reducing Air Emissions 12-2 (c)

7. Factors Affecting Air Emissions • Choice of Coating Materials • Choose low VOC, high solids surface coating materials. • VOC content is normally listed on Material Safety Data Sheets (MSDSs). Collision Repair - Reducing Air Emissions 12-2 (d)

8. Reducing Air Emissions From Autobody Repair Activities • Prep Coats • Use versatile products such as epoxy primers or self-etching primers. • May alleviate the need for additional surface coating operations • If these products are not acceptable -- use a wash-primer or metal conditioner conversion coating system. Collision Repair - Reducing Air Emissions 12-3 (a)

9. Reducing Air Emissions From Autobody Repair Activities • Primer-Surfacer • Minimize the number of coats applied. • Ensure that all major body imperfections are removed prior to priming operations (i.e. do not use a primer as a body filler.) • Use a primer gun with correct fluid tip/air cap combinations for each type of primer-surfacer. • If curing time of waterborne products is too long, consider using versatile urethane primers. Collision Repair - Reducing Air Emissions 12-3 (b)

10. Reducing Air Emissions From Autobody Repair Activities • When using a clear sealer, make sure the primer-surfacer is a color can be covered with the desired topcoat. • With transparent topcoats, the color of the undercoat may affect the color match of the topcoat. • Primer-Sealers • Use low VOC urethane primer-sealers as an alternative when possible. Collision Repair - Reducing Air Emissions 12-3 (c)

11. Reducing Air Emissions From Autobody Repair Activities • Choose primer-sealer in a color that is easily covered with the desired topcoat, or choose a tintable primer-sealer and tint it to an easily-covered color shade. • Sealers • Choose a sealer appropriate for each specific job. • If filling capabilities are required, use a primer-sealer in place of a sealer. Collision Repair - Reducing Air Emissions 12-3 (d)

12. Reducing Air Emissions From Autobody Repair Activities • Choose a primer-sealer of a color that can be easily covered with the coating to be sprayed, or choose a tintable primer-sealer. • Topcoats • Mix color coats in-house, making certain the formula for the proper shade of the specific color code is used. • Will help avoid the need for blending the finish to achieve a satisfactory color match. Collision Repair - Reducing Air Emissions 12-3 (e)

13. Reducing Air Emissions From Autobody Repair Activities • Keep good records of paint match information, including spray-out cards and detailed notes. • Use record keeping to help determine how much material should be mixed for the job. • Avoid the use of lacquer-based topcoats. • Choose low VOC topcoats that require fewer than three coats to achieve adequate coverage (polyurethane or urethane). Collision Repair - Reducing Air Emissions 12-3 (f)

14. Reducing Air Emissions From Autobody Repair Activities • Apply only the number of coats needed to achieve a quality finish. • Use high solids/low VOC clears to topcoat color coats. • Keep the addition of paint additives to a minimum. Collision Repair - Reducing Air Emissions 12-3 (g)