An electrostatic precipitator used in conjunction with a recirculation duct was developed to remove airborne pig dust from an environmental chamber. The collection efficiency of the precipitator was evaluated by using 3 applied voltage levels (-10.3, -11.0 and -12.1 kV d.c.) and 3 airspeeds (0.55, 0.76 and 0.95 m/s). The overall collection efficiency of the precipitator ranged from 18.5 to 96.4% at applied voltages of -10.3 and -12.1 kV, respectively. Removal efficiency was highest at 0.76 m/s for all applied voltages. An applied voltage of -12.1 kV produced ozone levels of 0.21 p.p.m., which exceeded the recommended level of 0.1 p.p.m.