<正> A generator to induce simulated underpressure of blast waves has been designed andapplied for the study of underpressure injuries in animals.The generator consists of a vacuumchamber

a vacuum pump

an experimental chamber

a membrane-rupturing device

and apressure-measuring system.When the pressure in the vacuum chamber is reduced with the suc-tion of the vacuum pump to a given level

the membrane separating the vacuum chamber andthe experimental chamber

in which the experimental animal is fixed

is ruptured instantly by asharp pointer.Underpressure occurs in the experimental chamber as soon as its pressure is re-duced rapidly.The physical parameters of the simulated underpressure of blast waves rangefrom-13 to-90 kPa for the peak level

1 to 90 ms for the decreasing time and 14 to 2000 msfor the duration.Animal experimentation with the generator verified that underpressure can in-flict injuries on living bodies as well.