![[logo] US EPA](http://www.epa.gov/epafiles/images/logo_epaseal.gif){kind=logo}
Module 3: Characteristics of Particles - Particle Size Categories - Practice Problems
-
Instructions:
- Work these problems on a sheet of paper and check your answers against those provided below.
-
#1 -
Select the correct EPA classification for the particle or
particulate matter described below.
-
EPA Classifications
-
Total Suspended Particulate Matter
-
PM10
-
PM2.5
-
Particles < 0.1
- Condensable Particulate Matter
Particle (Particulate Matter) Descriptions
-
A particle immediately released from a metallurgical process
that consists of 50 molecules clustered together prior to
agglomerating to form larger sized particles.
-
Particulate matter that was formed from gases immediately
after being released into the atmosphere.
-
Respirable particulate matter that falls into the coarse and
fine size categories.
-
Particulate matter, released from a source, which consists of
particles ranging in size from approximately 2 micrometers to
25 micrometers.
-
Fine particulate matter composed of nitrates.
-
Particulate matter that cannot usually be removed prior to
reaching deep into the human respiratory tract and can travel
hundreds of miles in the atmosphere due to its slow settling
characteristics.
-
Total Suspended Particulate Matter
-
-
Answer: i. d. Particles < 0.1
-
Particles as small as 50 molecules are categorized as being less
than 0.1 micrometer. These particles rapidly cluster to form larger
particles.
-
Answer: ii. e. Condensable Particulate Matter
-
Condensable particulate matter is formed from gases or vapors that
form particulate matter once released into the atmosphere.
-
Answer: iii. b. PM10
-
PM10 is considered respirable and includes particles in
the coarse, fine, and ultrafine range.
-
Answer: iv. a. Total Suspended Particulate Matter
-
Total suspended particulate matter includes particles with
diameters between 0.1 and approximately 30 micrometers.
-
Answer: v. c. PM2.5
-
PM2.5 are fine particles often composed primarily of
sulfates, nitrates, organic compounds, and ammonium compounds.
-
Answer: vi. c. PM2.5
- PM2.5 can stay airborne for hundreds of miles and usually is unaffected by the defense features of the human respiratory tract.
-
#2
-
Match the particle size with the appropriate size
category.
-
-
-
Answer: i. b. Coarse
-
Coarse particles range in size from 2.5 through 10 micrometers.
-
Answer: ii. a. Supercoarse
-
Supercoarse particles are greater than 10 micrometers in size.
-
Answer: iii. a. Supercoarse
-
Supercoarse particles are greater than 10 micrometers in size.
-
Answer: iv. c. Fine
-
Fine particles range in size from 0.1 to 2.5 micrometers.
-
Answer: v. b. Coarse
-
Coarse particles range in size from 2.5 through 10 micrometers.
-
Answer: vi. d. Ultrafine
- Ultrafine particles are less than 0.1 micrometer in size.