Perchloroethylene (PERC)

Perchloroethylene (PERC) [四氯乙烯 (PDF)][全氯乙烯 (PDF)] is a man-made chemical. It is most often used in dry cleaning and manufacturing. PERC is a non-flammable, colorless liquid that easily evaporates into the air. It has a smell that many people associate with dry cleaning.

PERC is present at very low levels in the air because of its widespread use. Higher levels of PERC may be found near businesses that use it, such as dry cleaners or auto repair shops. Some New York City residential buildings that share space with dry-cleaning shops also have high levels of PERC. However, not all dry cleaners use PERC.

If you live above or next to a dry cleaner, you may be exposed to dry cleaning chemicals that can affect your health. The NYC Health Department offers free home air testing for residents living by a dry cleaner. To request a free air test or see if you're eligible, call 311 and mention "PERC" or e-mail us at

Health Effects

The longer you are exposed to PERC the more health issues it can cause.

People who regularly use or manufacture PERC, such as dry cleaners, are more likely to have health problems from PERC. When there is a lot of PERC in the air—especially in closed areas with little air movement—one-time exposure to PERC can cause:

  • Dizziness
  • Headache
  • Sleepiness
  • Confusion
  • Nausea
  • Difficulty speaking and walking
  • Irritation to skin, lungs, eyes, nose and throat

People who are exposed to high levels of PERC for many years are at risk for problems with the nervous system, liver and kidneys, as well as certain cancers.

People who live or work in buildings that share space with dry cleaners that still use PERC may be exposed to low levels of the chemical. Though research is limited, it suggests that this level of exposure could cause color vision issues and mild effects on the central nervous system over time.

Regulating Dry Cleaners

Dry cleaners that still use PERC must follow federal, state, and local regulations to keep PERC vapors at a low level in their shops and out of neighboring homes and businesses. Employers must also protect workers from PERC exposure.

For more information, see Best Practices for Dry Cleaning Shops in Residential Areas (PDF) Other languages: [Español] [한국어] [中文] [简体中文]


Testing People

There are no readily available medical tests for residents to find out if their amount of PERC exposure. The best way to check if a resident is being exposed to PERC is to measure the air in the home for PERC.

Testing the Air

If you live on the first or second floor of an apartment building that is above or next door to a dry cleaner, the New York City Health Department offers free air tests (PDF) to make sure dry cleaners are following health regulations. Call 311 and mention PERC to see if you are eligible and request a free test. Air test results for PERC are measured in milligrams per cubic meter of air (mg/m3) or parts per million (ppm).

In homes, the New York State Department of Health recommends that the average air level of PERC not exceed 0.03 mg/m3 (0.004 ppm). Levels above 0.03 mg/m3 may indicate that dry cleaning equipment is not operating properly and needs to be fixed.

For workers, the Occupational Safety and Health Administration (OSHA) requires employers to keep air levels below 678 mg/m3 (100 ppm) over an eight-hour work day.

See OSHA's Reducing Worker Exposure To Perchloroethylene (PERC) In Dry Cleaning for more information.

When To Seek Help

If you believe you or your children are experiencing symptoms that you think might be related to PERC exposure, see your health care provider. Tell the provider when, how, and for how long you think you were exposed to PERC.

In case of an emergency, call the Poison Control Center at 212-POISONS, 212-VENENOS or (212) 340-4494. You can call 24 hours a day, 7 days a week.

For more information or to register a complaint about possible air quality impacts to your home from a dry cleaner, call 311.

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