AIR-QUALITY IN AN ANIMAL FACILITY - PARTICULATES, AMMONIA, AND VOLATILE ORGANIC-COMPOUNDS

Concentrations of ammonia, volatile organic compounds, particles, and mouse allergen were measured in an animal facility. Ammonia concentrat ions averaged less than 1 ppm, below-any health-based standards. The c oncentrations of volatile organic compounds were in the 5-15 mu g/m(3) range. Among the volatile organic compounds found, only the terpenes a-pinene and a-terpinol (which may be derived from the pine shavings u sed as bedding) were consistently present in concentrations greater th an outdoor air. The primary air contaminant present at concentrations high enough to be of known physiological significance was the mouse al lergen, Mus ml. To determine which activities in an animal room genera ted the highest concentrations of airborne Mus ml, a monitor that coun ted particles continuously was used. The particle counts were correlat ed with allergen levels in the worker's breathing zone (r50.83, p,0.05 ). Thus, a particle counter can be used effectively in animal facility to identify specific activities that generate high levels of both par ticles and allergen. Such activities included changing mice from soile d to clean cages, cleaning floors, and changing foam inserts in pressu rized individually Ventilated cages. To reduce exposure to allergen du ring cage changing, which is the major activity for an animal caretake r, a capture-type ventilated changing table was designed and tested. U se of such a table reduced exposure to allergen in the worker's breath ing zone from 4.961.1 to 2.160.3 ng Mus ml/m(3), a level comparable to background levels.