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Air Emissions Factors and Quantification

AP-42 Chapter 4: Evaporation Loss Sources - Frequent Questions

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How do you estimate emissions from wire coating by PVC extrusion? I understand that PVC resins used for pipe are likely to have fewer additives than PVC used for wire coating. However, the emissions from vinyl chloride and degradation products may be similar.

We don't believe the results of the pipe extrusion testing are applicable since the PVC resin used was not compounded. We know that resin additives will tend to be emitted during processing and could be the major component of emissions. We suggest that you run a thermo-gravimetric analysis (TGA) of the resin (as long as your Title V agency agrees with this approach). A TGA requires you to heat a sample of the resin and through weigh loss will give you an estimate of the VOC emissions. Another option is to conduct some testing on wire coating operations. Some resin manufactures have conducted testing of their resins and it may be possible to get some numbers from them.