Dry Cleaning Method Comparison Chart
| Method |  CO2 |  Wet Cleaning | PERC | GreenEarth | Hydrocarbon | Glycol Ether |
|---|---|---|---|---|---|---|
| What Is It? | Carbon dioxide – a colorless, odorless gas; under pressure, becomes liquid | Water | Perchloroethylene (PERC for short) is a toxic and environmentally dangerous solvent that dry cleaners have used for more than 40 years | A siloxane-based solvent (any of a large class of compounds that have alternate silicon and oxygen atoms) | A descendant of the petroleum-based solvents used in the early days of dry cleaning | A family of chemicals used in everything from antifreeze to household cleaning products; it's not clear what glycol ethers make up the cleaner |
| Solvent Manufacturers | Naturally occurring | Naturally occurring | Dow, Vulcan | Dow Corning, General Electric, Shin-Etsu | ExxonMobil Chemical, Chevron Phillips Chemical | R.R. Street, Dow, Rynex, Lyondell Chemical |
| # of Cleaners Nationwide | 35 | 85-100 | 35,000+ | 600-700 | Unknown | Unknown |
| Machines | Modern, high-pressure cleaning machines | Computer-controlled washing machines | Dry-cleaning machines | Modified dry-cleaning machines | Converted dry-cleaning machines | SolvAir machine is new, untested |
| Heat | NONE - better for your clothes (heat sets stains) | Computer-controlled | YES - 120+ degrees | YES - 120+ degrees | YES - 120+ degrees | YES - 120+ degrees |
| Chemical Odor | NONE | NONE | Strong chemical odor | None – but can be prone to bacterial growth leading to musty odor. Additional chemicals are marketed to kill the bacteria. | Slight odor | Slight odor |
| Pollution | NONE | NONE, with the exception of waste water | The EPA has established PERC as a known carcinogen and is regulated as a Hazardous Air Pollutant. According to a government study, PERC now contaminates up to 25% of U.S. drinking water. | None | Concerns for groundwater contamination | Glycol ethers are volatile organic compounds (VOCs), which means they are emitted into the air after performing their function; toxicity is currently unknown |
| Worker Health Safety | Low Risk | Low Risk | High Risk | Low Risk | Med. Risk | Med. Risk |
| Harmful Health Effects | NO RISK | NO RISK | May cause cancer in dry cleaning workers, serious negative health effects for people who live above dry cleaners, and harmful effects from direct repeated exposure to dry cleaned clothes | Download SEHSC fact sheet Download Winter 2008 Newsletter |
Comes with concerns about explosion, toxicity and the potential for groundwater contamination | Overexposure can cause anemia, irritation of eyes, nose and skin; some evidence that workplace exposure is hazardous to reproductive health |