Workplace exposure to rosin-based solder flux fume during hand soldering

The patterns and extent of exposure to rosin based solder flux fume have been investigated in two surveys and a number of individual site visits carried out by the UK Health and Safety Executive (HSE). Determination of solder fume was by measurement of airborne resin acid particulate. Both static and personal sampling was carried out over time periods ranging from 15 minutes to several hours. Resin acid concentrations were found to vary from less than 1 microgram m-3 to 2289 micrograms m-3. The effects of various types of local exhaust ventilation on resin acid concentrations have been observed. On-tool tip extraction systems were generally found to be the best control measure available; however good design, positioning and system maintenance is essential for efficient capture of the fume. The resin acid concentrations detected at these twenty-six sites suggest that the proposed British long and short term occupational exposure limits are realistically attainable targets, particularly where good working practices and/or effective fume control measures are in place.