reinforced plastic composites production mact summary

5. What HAP emission factors are used in this rule and how are they used?

Table 1 to Subpart WWWW of Part 63 presents a series of HAP emissions factor equations for open molding and centrifugal casting operations. These equations are specific to the type of resin and gel application and HAP emissions reduction technique used and allow sources to calculate HAP emissions factors based on HAP content and application method for each material that is used. The calculated HAP emissions factors are then averaged and compared to limits in the final standards to determine if the open molding and centrifugal casting operations are in compliance. The HAP emissions factor equations for open molding are identical to HAP emissions equations developed by the composites industry called the Unified Emissions Factors (UEF) as they existed at the time of final rule development. These equations can also be combined with resin and gel coat use to determine HAP emissions rates. Even though these equations may be identical to the Unified Emissions Factors, only the equations actually contained in Table 1 to subpart WWWW of part 63 may be used for purposes of compliance.