Development of a Thermal Spray Coating Generator and Exposure System for Toxicology Studies

Details

• Personal Author:
  Afshari A ; Antonini JM ; Lee EG ; McKinney WG
• Description:
  Thermal spray coating is a surface treatment process that enables different types of materials to be deposited on various substrates- metal, metal alloys, ceramics, and plastics. The process involves spraying a metal coating product which is melted by high temperatures and then sprayed under pressure onto a surface. Applications for thermal spray processes have a broad range across all industrial sectors. This technique is widely used in repairing bridges, water towers, wind turbines, pipelines, and ship tankers as well as in the automobile and aircrafts industries. During the process, large quantities of aerosols composed of fine and ultrafine metal particles are generated. Little is known about the physical (e.g., particle size and morphology) and chemical (e.g., metal composition, solubility, surface chemistry, metallurgy) properties of the particles formed during the process. The goals of this research were to construct a thermal spray coating generator and exposure system for toxicology studies and to characterize the properties of the formed aerosols during different spray coating processes in a laboratory setting. Initial studies have evaluated twin-wire arc thermal spray coating using P-MET 730 stainless steel consumable wire. In twin-wire arc thermal spraying coating, two consumable metal wires are fed independently into the spray gun. The wires are charged, forming an arc between them. The heat from the arc melts the wires generating metal particles which are entrained in an air jet from a spray gun. The entrained molten metal is then deposited onto a rotary substrate via compressed air. Count median electric mobility diameter was measured to be 196 nm with a geometric standard deviation of 1.5, using a scanning mobility particle sizer (SMPS). Importantly, a significant portion of the primary particles were observed via scanning electron microscopy (SEM) to be in the ultrafine size range with diameters <100 nm. The particles were primarily composed of iron, chromium, nickel, and manganese. With the development of this system, it is possible to investigate the pulmonary and systemic health effects associated with the inhalation of aerosols generated from different thermal spray coating processes in an animal model. [Description provided by NIOSH]
• Subjects:
  Aerosols Immune System Lung Metals Occupational Exposure Occupational Health Particulate Matter Respiratory System Safety Toxicology
• Keywords:
  Aerosol Particles Immune Reaction Inhalation Studies Lung Irritants Metal Fumes Metal Oxides Occupational Exposure Particle Size Spraying Operations Sprays
• ISSN:
  1096-6080
• Document Type:
  Text
• Genre:
  Abstract or Summary
• Place as Subject:
  California ; OSHA Region 3 ; OSHA Region 9 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  46
• Volume:
  174
• Issue:
  1
• NIOSHTIC Number:
  nn:20058864
• Citation:
  Toxicologist 2020 Mar; 174(1):46
• Federal Fiscal Year:
  2020
• NORA Priority Area:
  Manufacturing
• Peer Reviewed:
  False
• Source Full Name:
  The Toxicologist. Society of Toxicology 59th Annual Meeting and ToxExpo, March 15-19, 2020, Anaheim, California
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:c3a7938ce53c1c2cc383adcda88adba5352aba40ddf15ec20eb77a8439a16fe43074b8f0a29d607bd7c2a709cb3219ff47409c841e58303ef7e7fbb4f629dfae
• Download URL:
  https://stacks.cdc.gov/view/cdc/223243/cdc_223243_DS1.pdf
• File Type:
  [PDF - 539.13 KB ]