Environmental agricultural tractor cab filter efficiency and field evaluation.

To evaluate filter efficiency and performance of environmental enclosures for tractors, 3- to 4-year-old tractor enclosure combinations (cabs retrofitted to tractors after manufacturing) were studied at a custom pesticide applicators facility. Optical particle counters were used to measure the aerosol number concentration inside and outside the cab. The ratio of these concentrations multiplied by 100 is termed percentage penetration, the amount of the aerosol that penetrates into the enclosure.

Engineering controls for furniture strippers to meet the OSHA methylene chloride PEL.

This case study demonstrates how methylene chloride exposures during furniture stripping can be reduced to below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 25 ppm (as an 8-hour time-weighted average). Five surveys were conducted at one facility; the first four resulted in employee exposure geometric means from 39 to 332 ppm. For the fifth survey local exhaust ventilation was used at the stripping tank and the rinsing area, which together exhausted 138 m3/min (4860 ft3/min).

The impact of maintenance and design for ventilation systems.

Ventilation systems need to be designed to include access for cleaning and preventive maintenance. Without such access, the exhaust volume will deteriorate. Because of access difficulties and the many demands on their time, plant managers are sometimes errant in performing proper preventive maintenance.