The Bureau of Mines studied environmental blast effects in six occupied residential structures. Airblast, ground, and structure vibrations were measured both inside and outside residences for seven quarry production blasts. The vibrations of the houses generated noticeable internal noise, correlating with the arrival of the groundborne energy. The later arriving airblast wave was predominantly at low infrasonic frequencies (1.0 to 1.5 Hz) and had similar amplitude and frequency characteristics both inside and outside the structures. Significant structural motions resulted from the airblast overpressures for at least two of the seven blasts. The most severe airblast effect occurred at a house 1,800 feet from a 5,047-pound (200-lb/delay) blast. This structure was subjected to a peak of 0.16-In/sec particle velocity and 130 db(l) airblast. The wall of the second floor responded to the ground vibration and airblast by shaking at particle velocities of 0.15 And 0.28 In/sec, respectively.