When using fall-arrest systems, specialist assistance may be necessary to select appropriate equipment, provide effective training in use and inspection, and develop an emergency retrieval plan to recover a person suspended in a fall-arrest harness. People suspended by a fall-arrest harness for short periods of time may suffer serious health effects, or may have incurred injury during the fall prior to the fall-arrest device deploying.
The two buttons must be pushed at the same time and are located at a distance from each other that prevents simultaneous operation by one hand. The operation should be designed so that if either or both of the buttons are released, the hazardous action of the machinery and/or equipment cannot be reached, or if it can be reached, the mechanism returns to a safe state.
They are assembled from a standardized type of components. These consist of mechanical elements that control the movement in various ways, such as, gear trains, transistor switches, belt or chain drives, linkages, cam and follower systems, brakes and clutches, and structural components such as frame members and fasteners.
For potentially harmful substance exposures from machinery and equipment, such as mist, fumes, vapour or dust, and where it is not possible to control the emission at its source, ventilation and extraction systems are used to remove the hazardous emissions from the work environment.