VEHICLE-MOUNTED NEPHELOMETER FOR USE IN DESERT ENVIRONMENTS

Vehicles that are required to travel off-road in arid and semiarid con ditions can be exposed to high levels of airborne particles. The airbo rne material, typically sand, can be detrimental to the performance of air-breathing engines and other mechanisms. The U. S. Army, for insta nce, has experienced the influence of airborne desert dust during test ing of equipment at Yuma Proving Ground, and during critical operation s at other desert locations. To enhance testing of equipment under loa ding of airborne desert dust, a laser-based nephelometer has been cons tructed which provides the real-time measurement of dust mass per unit volume. The instrument is sensitive and provides a linear response to dust concentration levels from 0.01 to above 25 g/m(3). Important is that: (1) the light scattering technique is independent of particle si ze distribution in the sampling volume; and (2) the instrument is rugg ed to allow for mounting and operation on vehicles traveling off-road in the desert environment. (C) 1996 American Institute of Physics.