OCCUPATIONAL-HEALTH DATA AS A BASIS FOR PROCESS ENGINEERING CHANGES -DEVELOPMENT OF A SAFE WORK-ENVIRONMENT IN THE SODIUM-AZIDE INDUSTRY

The development of an occupational health system for a plant manufactu ring sodium azide has had to confront biological and hygienic difficul ties related to the nature of sodium azide, Sodium azide in pellet for m is used as the nitrogen generant for automobile air bags; however, i t is manufactured as a very fine powder making exposure control more d ifficult. Sodium azide is a rapidly active, vasodilatory hypotensive a gent that causes headaches and drops in blood pressure. Occupational h ealth assessment of the plant and its employees demonstrated the need for exposure control, based on inspection, interviews, health data, pr ocess and site review. Targeted studies demonstrated the nature and ma gnitude of health effect problems at this plant and the relationship t o azide exposure. Engineering and hygiene changes were developed in re sponse to the evidence of worker exposure demonstrated by the targeted studies. The occupational health surveillance system provided a monit or for temporal changes, Results appear to demonstrate over the period of the development of the program, the following changes: (1) reducti ons in evidence of subjective symptoms from azide exposure (health inc ident reports of headaches and other symptoms), (2) reductions in obje ctive signs of effects from azide exposure (drops in cross-shift mean arterial blood pressures), and (3) reductions in measured levels of az ide exposure. Future studies need to, validate the evidence of exposur e changes and to further identify additional sources of exposure. Inte rventions designed to reduce exposures need to be demonstrated to be e ffective and need to be monitored to demonstrate continuing effectiven ess.