OTC Committee
Discussion Paper for Potential Measures
Date updated: 09-01-21 03 – 13 - 09
Name of potential measure: Solvent Cleaning
Brief description of the measure being considered: Control measure will address VOC emissions from cold
cleaning machines (the major source of VOC emissions), open-top vapor degreasers, all types of conveyorized
degreasers and air-tight and airless cleaning systems that carry out solvent degreasing operations with a solvent
containing volatile organic compounds (VOC) [and the issue of including NESHAP halogenated solvents as
practiced under 2004 California rules must be considered]. Cleaning operations will use solvent with a material
VOC content of 25 g/l or less. The former vapor pressure limit (1.0 mmHg) is no longer used.
Previous programs, model programs or historical significance: The SCAQMD has had a solvent cleaning rule
since 1979 that has been amended and tightened many times to attain ever lower VOC emissions. They also have a
companion rule, 1171 (Solvent Cleaning Operations), that treats the use of solvents and solvent waste generated
during production, repair, maintenance, or servicing of products, tools, machinery and general work areas which
usually runs in tandem with rule 1122. Dropping the use of vapor pressure to set VOC limits started with rule 1171
when material VOC calculations were introduced late in 1999 and then was adopted into 1122 using the same 50
g/l VOC limits.
Major Issues: Likely not a problem as the SCAQMD rule 1122 went into effect mainly in 2005 with some
portions effective in 2006. However, without close attention to special exemptions for small but critical operations
such as aerospace, medical, specialized electronics, etc, significant resistance will be encountered. Exemptions for
specialized operations tend to be higher than in other rules and are somewhat state specific (that is, the OTC model
rule cannot include specialized operations that may be peculiar to only a few states, thus each state may be required
to search out these specialized operations).
Emissions reduction benefit: Difficult to say and more discussions with CA representatives are required to
determine the reductions . Anticipated to be in excess of 5 tons per year per million population. 13.0 tons per day
across the OTR
Control Cost Estimate: Not yet known, but likely to be in the range of $4,000 $1400 per ton VOC reduced.
Benefit for other pollutants: The current SCAQMD rule includes halogenated solvents such as
perchloroethylene, which are a health concern; included due to many stakeholder comments to add such coverage.
SCAQMD also was concerned that users could be tempted to substitute non-VOC solvents that pose a health risk
to avoid the solvent cleaning rule. OTC must give this issue careful consideration as these are exempt solvents
which pose no ground-level ozone problem but do pose a health risk to employees operating the equipment.
National program possibilities: Yes, but it is unlikely that EPA would be interested in developing a national
solvent cleaning rule more stringent than already exists for halogenated solvents.
Author Contact info:
Gene Pettingill
State of Delaware
Dept. of Natural Resources & Environmental Control
715 Grantham Lane
New Castle DE 19720
302-323-4542 302-323-4598 fax
gene.pettingill@state.de.us