On Aug. 25, 2005, the U.S. Environmental Protection Agency (EPA) promulgated a twenty-page direct final rule affecting composite parts manufacturers. Packed with corrections and clarifications, the rule will affect every facility that is subject to the Reinforced Plastic Composites Maximum Achievable Control Technology (MACT) standard imposed under the National Emission Standards for Hazardous Air Pollutants (NESHAP) program.

Due to the fast-approaching April 21, 2006 compliance deadline, the regulatory changes were issued without prior proposal. The changes automatically become effective on Oct. 24, 2005, unless EPA receives written comment on a simultaneously published proposal by Sept. 26, 2005 or a public hearing is requested by Sept. 6, 2005. If either event transpires, EPA will publish a notice in the Federal Register (FR) that describes which changes will become effective and which changes will be delayed until the agency can review them further. Copies of the direct final rule (70 FR 50117) and proposal (70 FR 50113) may be downloaded from the EPA Web site. This Web page also is a good reference to determine whether EPA has published any additional regulatory actions affecting composites MACT regulations in 40 Code of Federal Regulations (CFR) Part 63, Subpart WWWW.

Minor corrections and clarifications comprise the bulk of the direct final rule. Examples include adding a word to a definition and increasing some emission limits by less than 1.5 percent. These changes "fine tune" the regulations to remove inconsistencies and avoid confusion. The accompanying table provides a brief summary of most regulatory revisions and includes regulatory citations.

One major change deletes the phrase "compliant materials" from regulatory text. This phrase was problematic because emissions from composite parts manufacturing operations depend on several factors, including the application method and use of emission controls (such as vapor suppression or add-on controls), as well as the organic hazardous air pollutant (HAP) content of the resin or gel coat. According to the direct final rule, a specific resin or gel coat, as applied, is "in compliance" if its emissions do not exceed the applicable emission limit in Table 3.

A related change deletes the fourth column from Table 3, which contains emission limits for open molding, centrifugal casting and continuous lamination/casting operations. As published originally, the fourth column contained the "highest organic HAP content for a compliant resin or gel coat." The column was deleted for several reasons. In the preamble to the direct final rule, EPA states that although the maximum organic HAP concentrations were originally intended only as examples, they were being interpreted as absolute limits. As pointed out in the October 2003 "Composites & Compliance" column, the maximum concentration numbers in the fourth column of Table 3 were misleading because they did not take into account the use of vapor suppression or other controls. By deleting the column, EPA removes a source of confusion and reinforces the idea of resins and gel coats being "in compliance" based on emissions calculated using applicable equations from Table 1.

Note, however, that the "same resin" compliance option is still based on maximum organic HAP concentrations listed in Table 7. Under this compliance approach, a facility can meet a specified organic HAP emission limit for one operation type (e.g., filament winding) and use the same resin(s) for all operations of that resin type. For example, if the resin type is non-corrosion-resistant, non-high-strength (non-CR/HS) resin, all other non-CR/HS resins used in mechanical application, manual application or centrifugal casting operations may contain up to 45.0 percent organic HAP according to Table 7. This is a significantly greater HAP content than would be allowed based on emission limits in Table 3. Note, however, that EPA added several footnotes to Table 7 that impose more stringent requirements on certain types of manufacturing operations. According to footnote 3 to Table 7, only nonatomized (nonspray) mechanical resin application can be used for most same-resin compliance options. This change closes a major loophole that was present in the original rule.

Other significant changes in the direct final rule involve emission calculations, emission limits and compliance options. Facilities with open molding, centrifugal casting and/or continuous lamination/casting operations are most affected by these changes, which will be explained in this column in the December 2005 issue of Composites Technology, assuming that the changes become effective in late October.

To obtain an updated version of 40 CFR Part 63, Subpart WWWW regulations that incorporates the regulatory changes announced in the Aug. 25, 2005 direct final rule, go to the U.S. Government Printing Office's Web site after Oct. 24, 2005. Make sure that the e-CFR data is current as of Oct. 24, 2005 (or later); the currency date is usually highlighted in red. Then click on "Boolean" under "Advanced Search" on the left navigation bar. When the next page is displayed, retrieve the entire regulatory text for Subpart WWWW by entering the following search criteria. In the box after "Enter a Title Number," type in "40". In the box after "Retrieve," type in "63" and select "Part Number" from the drop-down box. In the next line after "and," type in "WWWW" and select "Subpart" from the drop-down box. Then click on "Submit Search." If multiple search results are displayed, choose the one that contains "Subpart WWWW" in its title.