The use of local exhaust ventilation for reducing worker exposure

Introduction

Many industrial processes release airborne contaminants into the workplace. The inadequate control of these can allow them to enter the breathing zone of workers’ resulting in inhalation exposure. One method of minimising exposure is to apply extraction at the source of the contaminant generation, thereby removing the hazard before it enters the workplace air. This technique is usually referred to as local exhaust ventilation (LEV).This article explains LEV, its relationship to the hierarchy of control, the different generic hood designs, including examples used in industry, and the steps that need to be taken to achieve successful and reliable control.…