Use of local exhaust ventilation to control aerosol exposures resulting from the use of a reciprocating saw during an autopsy.
American Industrial Hygiene Conference and Exposition, May 19-23, 1997, Dallas, Texas. Fairfax, VA: American Industrial Hygiene Association, 1997 May; :40
In December of 1995, investigators from the National Institute for Occupational Safety and Health responded to a health hazard evaluation request from the county coroner's office of a large metropolitan area. Specifically, the request asked for assistance in evaluating the use of reciprocating saws during forensic autopsies and the resulting operator exposure to generated bone, blood, and tissue fragments. Two reciprocating saw models were evaluated during the conduct of six examinations; an electric StrykerŪ saw and a pneumatic saw equipped with local exhaust ventilation (LEV). The generation of aerosols was monitored in real-time with light scattering instruments including the Met One Model 227 Handheld Laser Particle Counter for area measurements and the Handheld Aerosol Monitor (HAM) for personal breathing zone (PBZ) measurements. Integrated PBZ samples for tissue and bone fragments were also collected using 37-millimeter polyvinyl chloride filters analyzed by optical microscopy. Additionally, spectral noise samples were collected with a Larson-Davis Laboratory Model 2800 Real-lime Analyzer and a Larson-Davis Laboratory Model 2559 1/2" random incidence microphone. For the area measurements, peaks were observed during the use of the electric Stryker saw for particles greater than 1 um. These peaks corresponded to the use of the reciprocating saw on the cranial region of the decedent and were at least an order of magnitude above the baseline. Peaks were not observed at any of the measured particle size cut points with the pneumatic saw equipped with LEV Integrated PBZ samples agreed with the real-time measurements indicating an 88% reduction in the concentration of bone and tissue fragments (0.037 to 0.004 fragments/cubic centimeter) for the operating forensic technician. These results indicate that saws equipped with LEV exhibit lower generated aerosol concentrations outside of the capture zone of the hood. Additionally, peaks observed with the HAM collected on the forensic technician indicate that aerosols generated by the use of unventilated saws are capable of reaching the worker breathing zone. The noise data showed little difference between the two types of saws. Although noise levels for either saw can approach 95 dB(A), the short amount of time, 5 minutes or less, which the pathologist or technician are subjected to the noise lowers the time-weighted average (TWA) value below any applicable evaluation criteria.
Workers; Work-areas; Hazards; Environmental-hazards; Health-hazards; Exposure-levels; Blood-cells; Body-fluids; Aerosols; Aerosol-particles; Biohazards
American Industrial Hygiene Conference and Exposition, May 19-23, 1997, Dallas, Texas