 Over the last few decades, California 

has adopted policies for restricting, 

eliminating use of TCE

 Safer viable and cost effective 

alternatives are available and used

 Based on California’s actions and 

experience, EPA can phase out or 

restrict TCE use in the three applications
 Intermediate in production of refrigerants

 Vapor degreasing of fabricated metal 

parts

 Cold cleaning

› Equipment

› Handwipe

› Spotting chemicals 

 Aerosol cleaning
 No flash point

 Fairly high boiling point

 Aggressive solvent

 Suitable for removing heavy oil, grease

 High evaporation rate
 Solvent heated to its boiling point in a vapor 

degreaser 

› stainless steel tank with a heater in the bottom 

and cooling coils around the inside perimeter

› Liquid and vapor zone

 Parts lowered into degreaser in basket

› Hot solvent in vapor zone condenses on part 

carrying contaminants into liquid

 Many types of vapor degreasers

› Conveyorized

› Batch open top

› Airless/Airtight

 Open tank or remote reservoir or flushing 

operation where solvent is at room 

temperature

 Small squeeze bottles or table containers

› Solvent applied with rags or wipes

 Exposure to workers higher than for 

vapor degreasers

› Solvent not contained by cooling coils

 Carrier solvent or cleaning solvent

 Used in aerosol cans, generally with a 

propellant

 Exposure is higher than for other 

applications

› TCE is in breathing zone

 Identify problem where safer alternative is needed in 

industrial or consumer product application

 Work with several companies using the operation 

 Identify, develop, test and demonstrate alternatives 

that perform well and are cost effective

 Work with regulatory agency to adopt/implement 

regulation

 Anticipate what alternatives may be used and try to 

prevent adoption of regrettable substitutes

 IRTA’s work has led to reduction in use of hazardous 

substances in California by more than 100 tons per 

day
 TCE used extensively in vapor degreasing 

and cold cleaning in the 1960s and 70s

 TCE designated as photochemically

reactive (VOC)and carcinogen in early 

70s

 Most users in California used TCA or PERC

 In 1990s, EPA adopted the NESHAP and 

production of TCA and CFC-113 was 

banned because of ozone depletion

› Thousands of vapor degreasers using TCA
 Most users converted to water-based cleaners 

and systems

› Water-based cleaning evolved and improved

 Some users converted to regrettable substitutes

› NPB began to be used

 Local air districts adopted increasingly stringent 

VOC regulations on vapor degreasing and 

cold cleaning in 1990s

 After 2000, local air districts and CARB 

continued to adopt VOC regulations and 

began banning the use of chlorinated solvents 

(PERC, TCE, methylene chloride) in many 

applications
 SCAQMD regulations set 25 gram per liter 

VOC limit for open top vapor degreasers 

and cold cleaning units

› Must use airless/airtight equipment with TCE

› May be as few as 25 TCE degreasers statewide

› Eliminated use of NPB

 CARB banned use of chlorinated solvents in 

automotive aerosol cleaners

› Initial conversion to hexane, other VOC solvents

› CARB set low VOC limit so TCE, hexane cannot 

be used
 IRTA worked with users to find 

alternatives for hundreds of vapor 

degreasing applications

› Virtually all converted to water-based 

cleaning systems

 Case study examples

› Nameplate company (conveyor spray)

› Contract cleaning company (ultrasonic)

› Aerospace subcontractor (spray cabinet)

 IRTA conducted EPA sponsored project 

to find alternatives to VOC solvents in 

repair and maintenance cleaning

› Used by auto repair and industrial facilities

› Some used TCE

› Remote reservoirs, batch systems

 Worked with many facilities of both types

› Found best way to optimize use of waterbased cleaners for the application
 SCAQMD passed regulation that 

became effective in 1999

› 40,000 operations converted

› Reduced VOC emissions by 18 tons per day

 Over next several years, other local air 

districts in California adopted similar 

regulations

› VOC reduction in state of 36 tons per day

 Water-based cleaners are now 

institutionalized in this use
 Case study examples

› Aerospace subcontractor (water-based 

cleaning)

› Auto repair facilities (water-based cleaning)

› Silicone implantable medical devices 

(eliminated contaminants)

 IRTA conducted EPA/HESIS/CARB 

projects to find alternatives to VOC and 

chlorinated solvents in automotive 

aerosol cleaning applications

› Used by auto repair, industrial facilities and 

consumers

› Included brake cleaners, general purpose 

degreasers, carburetor and fuel injection 

system cleaners, engine degreasers

› Worked with about 25 auto repair facilities 

and some consumers

 Developed and tested alternatives

› Water-based, acetone, soy

 IRTA project led to CARB ban of chlorinated 

solvents and VOC content restrictions

› Eliminated use of TCE and some regrettable 

substitutes

› Reduced VOC emissions by 10 tons per day

 CARB restricts TCE use in other aerosol 

applications

› IRTA worked on alternatives in some other 

applications
 Case study examples

› Automotive dealership (water-based brake 

cleaning systems)

› Auto repair facility (water-based spray 

bottles)

› Energized electrical equipment cleaning 

(carbon dioxide pellet blasting/snow)

 TCE poses high risk to workers and 

community members in vapor 

degreasing, cold cleaning, aerosol 

applications

 Alternatives available for all applications

› Demonstrated in the California experience

 Vapor degreasing

› Safer alternatives have been demonstrated

› EPA should ban TCE or restrict its use to 

airless/airtight systems
 Cold cleaning applications

› Dow Chemical, manufacturer of TCE, no 

longer recommends its use in cold cleaning

› Cannot control exposure

› Safer alternatives have been demonstrated

› EPA should ban it

 Aerosol applications

› Can reformulate with safer alternatives in all 

cases

› EPA should ban it
Dr. Katy Wolf

Institute for Research and 

Technical Assistance (IRTA)

8579 Skyline Drive

Los Angeles, CA 90046

Phone (323)656-1121

Cell (818) 371-9260 

Fax (818) 656-1122

kwolf.irta@earthlink.net

www.irta.us