Aerosol 101: generation and behavior of airborne particles (aerosols).

Details

• Personal Author:
  Baron, Paul
• Description:
  What is an AEROSOL? Simply defined- tiny particles or droplets suspended in air. The haze in the picture on the right is caused by light scattering from numerous water/oil droplets and mineral particles released into the air from the drilling of rock. Are Aerosols dangerous? The air we breathe always contains solid particles or droplets and is therefore an aerosol. These aerosol particles can be from natural sources or man-made sources. Sometimes the particles are of type that, at sufficient concentration, are toxic to our body. The organ in our body most sensitive to particle exposure is the respiratory system. Toxic Aerosols!? Our respiratory system is efficient at removing aerosols, but if they fall within particular size ranges, are highly concentrated, or toxic, they may cause adverse health effects. They may also deposit on skin or eyes, generally only causing irritation, though more toxic effects may occur. Very small particles may pass through the skin and enter the body that way. Soluble particles may dissolve and pass through the skin. Aerosol Assessment in the Workplace: Types of Measurements: Sampling, usually with a filter and pump, provides a sample that can be analyzed in the lab for specific chemicals, quantity of dust, particle shape (fibers), etc. Direct reading instruments allow continuous observation of dust concentrations, e.g., mass or concentration or size distribution, but do not usually provide specifics of the aerosol type. The most accurate assessment of worker's exposure is measurement with a personal sampler, i.e, a collection or measurement device placed on the worker's chest. Techniques for control of exposures can use either personal samplers or (fixed) area measurement devices. Direct reading devices allow rapid assessment of the effectiveness of dust control devices or strategies. This document also covers the following: I. Particle size range; II. Inhalation & lung deposition; III. Particle behavior: Settling, impaction, electrostatic effects; IV. Particle generation: Energy input, size, charge, humidity. Scenarios: Letter release and Carpet release; and VI. Particle collection and measurement, including Filter sampling (Filter efficiency, pore size, filter type; Sufficient volume for analysis; Dries particles because of continuous air flow. Removal from filter can be an issue) and Impactor sampling (Cascade impactor: 3 to 8 stages, size resolution; Sufficient volume for analysis; Dries particles, though less than filter; Inert (oiled?) surface or direct to growth medium).
• Subjects:
  Accidents, Occupational Air Pollutants, Occupational Air Pollution, Indoor Manufacturing And Industrial Facilities Nitrosamines Occupational Health Preceptorship Safety Workplace
• Keywords:
  Aerosol Particles Aerosols Aerosol Sampling Airborne Particles Filters Particle Size Particulate Dust Sampling Methods
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Genre:
  Other
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DART - Division of Applied Research and Technology
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-40
• NIOSHTIC Number:
  nn:20059634
• Citation:
  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, 2004 Dec; :1-40
• Federal Fiscal Year:
  2005
• Peer Reviewed:
  False
• Source Full Name:
  National Institute for Occupational Safety and Health
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:625cd7d602de3dc88538f8ff4e9c61113c2408e10465a2c05d75cf5361953e43ded7b16299283519a570b747bf7152cb2c0c1f6e491cd768906a323fc4275b88
• Download URL:
  https://stacks.cdc.gov/view/cdc/181869/cdc_181869_DS1.pdf
• File Type:
  [PDF - 346.14 KB ]