DuPont SHE Excellence Center
1007 Market Street
Wilmington, DE 19898
February 28, 2011
Mr. Gene M. Pettingill
Delaware Dept. of Natural Resources and Environmental Control
Division of Air Quality
715 Grantham Lane
New Castle, DE 19720
gene.pettingill@state.de.us
Subject OTC Model Rule for Solvent Degreasing 2011 - Stakeholder Review Draft 082710B GMP
Dear Mr. Pettingill:
The DuPont Company appreciates the opportunity to offer comments and suggestions on the
Ozone Transport Commission's (OTC's) draft 2011 Model Rule for Solvent Degreasing. DuPont
corporate policies actively support reasonable and flexible regulations that promote regionally
consistent state rules to protect human health and the environment.
Several DuPont Businesses manufacture and distribute fluorinated solvents for vapor degreasing
applications. DuPont fluorinated solvent blends offer a unique line of products that are both
inherently safe, low toxicity, and non-flammable. They are used in small volumes in specialized,
niche applications such as those found in the medical, optics, aerospace, electronic (printed
circuit board) and precision cleaning industries which require stringent cleanliness levels. After
reviewing the Draft Rule, we have a number of comments and suggestions to ensure that the
above specialized applications requiring vapor degreasing can still rely on the products they use
and have certified thru QA/QC procedures that their manufactured products meet and/or exceed
their customer's cleanliness requirements. Because these materials are used in small specialty
applications, we believe the suggested changes are consistent with the environmental goals of
the model rule.
Our primary concern with the Draft Solvent Degreasing Rule is the very low VOC concentration
limitation. The Draft Rule requires VOC content to be 25 grams/Liter, or approximately 2.5 weight
percent. Some fluorinated solvent blends cannot meet this standard, and the only one that does
is a Class 2 regulated ozone depleter (HCFC-225), which will be phased out as part of the
Montreal Protocol on January 1, 2015. Also, a rule with only the 25 g/L standard will promote the
use of “less safe” solvents in air tight machines. These less safe, more toxic solvents become
economically attractive if air tight machines are mandated or the only alternative.
We therefore suggest that OTC consider including an alternative standard based on California's
use of Maximum Incremental Reactivity (MIR) values, or expanding the list of exempt applications
such as those found in the aerospace, electronics, and precision cleaning industries.
MIR Alternate Standard
CARB has published MIR values for over 1000 organic compounds. Ethane, the upper
benchmark for VOC delisting petitions, has an MIR value of 0.28. The MIR values of organic
compounds on the CARB list range from 0.014 to over 20. An MIR standard could be set, for
example at 1.7 MIR, and thus solvents or solvent blends would be exempted if less than 1.7 or a
weighted average if the solvent was a blend of organic compounds re-measure it. This alternate
standard would restrict highly reactive solvents but allow use of solvents with low photochemical
reactivity. The model rule implementation could be implemented with the addition of CARB's
MIR table published in Subchapter 8.6, Article 1, section 94700.
Additional Specialized Application Exclusions
Another option for providing certain specialized industries with extreme cleanliness requirements
is to expand the exemptions currently in the Draft Model Rule under section 7.0. DuPont
recommends that vapor degreasers used for aerospace, optics, electronic, and precision cleaning
industry parts cleaning be included with the medical and motion picture film cleaning exclusions.
Vapor degreasers in these specialized applications represent a very small percentage of the
solvent degreasing usage. Cold degreasers represent 85% of solvent degreasing, whereas
specialized vapor degreasing applications in aerospace and electronics industries is estimated to
be less than 3 %.
Another exemption to consider is a deminimis emission limit of 15 lbs/day of VOC emissions
below which regulation of a source would not be required. Many state regulations already
provide this allowance in their general VOC regulations, and we recommend that the Draft Model
Rule also incorporate this provision for insignificant VOC emissions from small vapor degreasing
equipment.
Minor Corrections
The following comments are very minor and identify some possibly unintended references to
California's South Coast Rule # 1122 and some of their state-specific procedures. See following
pages for references to "CARB" and SCAQMD":
Section 2. Definitions - p.9, definition "y";
Section 5. Compliance Test Methods - p.15, section (a), (g)(1) and (g)(2);
If you have any questions concerning these comments or need additional information, please
contact me at (302) 774-8043, or Robert A Lee (302) 545-5465.
Paul R. Jann
Sr. Regulatory Consultant
DuPont Engineering Environmental Section
Wilmington, Delaware
CC: Alexander Ryan-Bond (arbond@otcair.org)