Evaluation of Exposure to Crystalline Silica, Welding Fume, and Isocyanates During Water Heater Manufacturing

Details

• Personal Author:
  Methner, Mark M. ; Page, Elena H.
• Corporate Authors:
  National Institute for Occupational Safety and Health
• Description:
  The Health Hazard Evaluation Program received a union request about employees' exposures to silica during tank finishing operations, welding fume during tank fabrication, and methylene diphenyl diisocyanate (MDI) during tank insulation using a spray foam application. We measured exposure to airborne crystalline silica, welding fume, and MDI, held medical interviews, administered medical questionnaires, and collected blood for biomarkers of isocyanate exposure and sensitization. We found overexposure to crystalline silica during brushing, tank and flue spraying, and mill room operations. Methylene diphenyl diisocyanate and welding emissions were below occupational exposure limits. Employees reported symptoms consistent with work-related asthma. Two employees had MDI-specific IgE, consistent with MDI asthma, in their blood. Five employees had MDI-specific IgG in their blood, indicating recent exposure to MDI despite the use of engineering controls and personal protective equipment. Some employees in foam booths cut slits in their Tyvek suit to aid in cooling, creating a potential for skin exposure to MDI. Some ventilation controls were either not working or were ineffective in containing airborne contaminants. Improvements in ventilation system design, use, and maintenance are needed. The employer should also begin a medical surveillance program for employees exposed to MDI and silica and provide training on the hazards of working with both.
• Subjects:
  • Air Pollutants, Occupational
  • Antibodies
  • Asthma
  • Asthma, Occupational
  • Biomarkers
  • Blood
  • Dust
  • Environmental Exposure
  • Environmental Monitoring
  • Ferrous Compounds
  More +
• Keywords:
  • OSHA Region 5
  • Health effects
  • Manufacturing
  • Welders
  • Welding
  • Welding fumes
  • 4,4-Methylene diphenyl diisocyanate
  • Industrial processes
  • Spraying operations
  • Exposure assessment
  More +
• Source:
  Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, HHE 2015-0076-3282, 2017 Jun ; :1-23
• Series:
  Health Hazard Evaluation Reports (HHE)
• DOI:
  https://doi.org/10.26616/NIOSHHHE201500763282
• Document Type:
  Text
• Genre:
  Field Study
• Place as Subject:
  Michigan ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DSHEFS - Division of Surveillance, Hazard Evaluations, and Field Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  30 pdf pages
• Contributor:
  Booher, Donald E. ; Chiu, Sophia ; Feldmann, Karl D. ; Galloway, Ellen ; Mackenzie, Barbara ; Marlow, David ; Moore, Kevin ; Watts, Shawna
• NIOSHTIC Number:
  nn:20049994
• NTIS Accession Number:
  PB2017-102640
• Citation:
  NIOSH 2017. Exposure to crystalline silica, welding fume, and isocyanates ; during water heater manufacturing. By Methner MM and Page EH. Cincinnati, OH: ; U.S. Department of Health and Human Services, Centers for Disease Control and ; Prevention, National Institute for Occupational Safety and Health, Health Hazard ; Evaluation Report 2015-0076-3282,
• CAS Registry Number:
  • 4,4’-methylene diphenyl diisocyanate (CAS RN 101-68-8)
  • Crystalline silica, quartz (CAS RN 14808-60-7)
  • Ferric oxide (CAS RN 1309-37-1)
  • Manganese (CAS RN 7439-96-5)
  • Silica (CAS RN 7631-86-9)
• Federal Fiscal Year:
  2017
• NORA Priority Area:
  Services
• Peer Reviewed:
  False
• NAICS and SIC Codes:
  335228 - Other Major Household Appliance Manufacturing - (NAICS)
• Download URL:
  https://stacks.cdc.gov/view/cdc/172387/cdc_172387_DS1.pdf
• File Type:
  [PDF - 1.57 MB]
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:61267dd9c1fe0528b59847096a8b9d2e11b6dcb34a47889b76f3508e18298a3f2d7b51e9222893e06b19835c08ebd0f6376fb6875e2429bf5f6ffe864cd1992b