Measurements of solvent and lead release in a microcircuit production facility

Details

• Personal Author:
  Conroy LM ; Franke JE ; Scheff PA ; Wadden RA ; Yu-X-M
• Description:
  Ventilation and air concentrations were collected in two areas within a microcircuit production facility. In one area (-2800m3), methyl chloroform was used as a solvent In three degreasers to clean parts which had been processed in a lead reflow oven. None of the degreasers had local exhaust systems. One-hour average concentrations were measured, using adsorption on charcoal tubes and a GC-FID analytical finish, at 0.6 m and 1.4 m from each degreaser for a total of 12 hours over two days. Board through-put and other measures of source activity were recorded for each of the degreasers at two-minute intervals. The average near concentration was 23.8 ppm and that further away, 8.7 ppm. Average concentrations of dioxane, a contaminant of the methyl chloroform, were 2.36 mg/m3 at 0.6 m and 0.63 mg/m3 at 1.4 m away from the degreaser with the greatest solvent emissions. Measurements of concentration and air flow rates were also made on supply and exhaust air. A mass balance on the space over the two days yielded an equivalent emission rate from all three degreasers of between 141 and 171 kg of methyl chloroform/month. This was In good agreement with the usage value of 132 kg/month estimated from inventory records over a 2 month period. The other space (-5200m3) contained three wave soldering lines, each served by a local exhaust (partial enclosure) system. One-hour air samples were collected on polycarbonate filters at a calibrated pump rate of 3-5 lpm, and were analyzed for 29 elements using PIXE (proton induced x-ray emission). Twelve 1-hr periods were monitored over two days by sampling at two locations at different distances from each wave soldering machine, and In the duct of each local exhaust system. Observations of source activity, such as board throughput and frequency and duration of lead pot dedrosslng, were recorded at two-minute intervals. For lead, the average near concentration (i.e., within 1.2 m of a lead pot) was 3.57 u/m3. the far value (air recirculation) was 1.88 p.g/m3. and 17.94 ug/m3 was measured In the hoods. Hood concentrations much higher than room values were found for lead and tin (major components of solder). chlorine and potassium (from the flux added before soldering), and sulfur and silicon, indicating that these elements were integral to the soldering process. This pattern was not seen for concentrations of other elements, such as calcium, iron, nickel, copper, strontium, molybdenum, erbium, lutecium, hafnium and tungsten. For both spaces, the relationships between source activity and hourly concentrations provide a more specific measure of the emissions from each device. [Description provided by NIOSH]
• Subjects:
  Air Movements Chlorine Copper Environmental Monitoring Ferrous Compounds Lead Nickel Occupational Health Safety Solvents Sulfur Compounds Tungsten Ventilation

  More +
• Keywords:
  Air Flow Air Samples Calcium Cleaning Compounds Dioxane Emission Sources Filters Hafnium Iron Methyl Chloroform Molybdenum Monitoring Systems Potassium Sampling Silicon Soldering Strontium Sulfur Compounds

  More +
• Publisher:
  American Industrial Hygiene Association
• Document Type:
  Text
• Funding:
  Cooperative Agreement ; Grant
• Genre:
  Abstract or Summary
• Place as Subject:
  District of Columbia ; Massachusetts ; OSHA Region 1 ; OSHA Region 3
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  83
• NIOSHTIC Number:
  nn:20048364
• Citation:
  American Industrial Hygiene Conference and Exposition, Jun 1-5, 1992, Boston, Massachusetts. Fairfax, VA: American Industrial Hygiene Association, 1992 Jun; :83
• CAS Registry Number:
  1,1,1-Trichloroethane (CAS RN 71-55-6) ; Calcium (CAS RN 7440-70-2) ; Chlorine (CAS RN 7782-50-5) ; Copper (CAS RN 7440-50-8) ; Hafnium (CAS RN 7440-58-6) ; Iron (CAS RN 7439-89-6) ; Molybdenum (CAS RN 7439-98-7) ; Potassium (CAS RN 7440-09-7) ; Silicon (CAS RN 7440-21-3) ; Strontium (CAS RN 7440-24-6) ; Sulfur (CAS RN 7704-34-9) ; Tin (CAS RN 7440-31-5) ; Tungsten (CAS RN 7440-33-7)
• Federal Fiscal Year:
  1992
• Performing Organization:
  Center to Protect Workers' Rights, Washington, DC
• Peer Reviewed:
  False
• Start Date:
  19900928
• Source Full Name:
  American Industrial Hygiene Conference and Exposition, Jun 1-5, 1992, Boston, Massachusetts
• End Date:
  19961231
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:c4f8e94d5a66471f0ca682a9e6b740012e5bef44ef5597ecd1228d7abe51c436a8aac694e2bd2cd28c96c20ef5a8bd5fd42e00de24a60523cacfc17454478831
• Download URL:
  https://stacks.cdc.gov/view/cdc/203131/cdc_203131_DS1.pdf
• File Type:
  [PDF - 369.88 KB ]