Embalmers are exposed to formaldehyde at concentrations averaging up to 9 parts per million (ppm) during embalming. Short-term exposures to this strong-smelling gas cause eye, nose, and throat irritation at levels up to 5 ppm. At levels from 10 to 20 ppm, it causes cough, chest tightness, and unusual heart beat; and from 50 to 100 ppm, fluid on the lungs, followed by death. Exposure to formaldehyde over a long time may also cause cancer. NIOSH engineers designed and evaluated a local exhaust ventilation [LEV] system that effectively reduces embalmer's exposure to formaldehyde below the OSHA permissible limit of 0.75 ppm, as an 8-hr time-weighted average exposure.