1. DESIGN ENGINEER
DESIGN ENGINEER Colmac Coil has an immediate opening
for a Production Design Engineer. Compensation includes a
competitive salary, medical and dental insurance benefits and
401K plan.
Responsibilities Include: -Create fabrication and assembly
drawings, wiring diagrams and bills of materials for the
manufacture of products -Provide engineering support on
production issues -Write technical documents and procedures -
Provide design input on new and custom products -Other
projects as assigned.
Requirements: -4-Yr Engineering degree -High Level of
Proficiency in SolidWorks and AutoCAD -Working knowledge
of Outlook, Word and Excel -Problem Solving and
Troubleshooting Skills -Attention to Detail -Ability to Perform
Under Stress -Team Player -Positive Work Attitude.
IF INTERESTED, PLEASE SUBMIT RESUME AND COVER
LETTER TO: Brian Culler, E-mail: [email protected] Colmac
Coil Manufacturing, Inc.
Learning Objectives
Upon completion of this unit, students should be able to:
1. Discuss the difference between risk managers and risk
assessors.
2. Identify and discuss the four main steps of risk assessment.

2. 3. Evaluate the role of uncertainty and variability in risk
assessment.
4. Discuss the elements of risk communication to the general
public.
5. Evaluate the differences between conducting risk assessments
for carcinogenic and non-carcinogenic substances.
6. Define the hazard quotient and discuss how it is used to
evaluate the overall risk associated with a substance.
7. Define common terms encountered in performing a risk
assessment.
Written Lecture
After the toxicity and epidemiological data on a chemical has
been collected, how do we decide what levels are safe for public
health and the environment? Regulators use the process of risk
assessment to set pollutant emission levels based on the benefits
and consequences to society. In setting these limits, the
exposure to the pollutant, as well as its toxicity, are considered.
However, as Phalen & Phalen (2013) point out, there are gaps in
the toxicity data due to the fact that most of the data is for large
exposures. Our everyday exposure is more moderate, and there
is uncertainty regarding the extrapolation of the high-exposure
data to lower levels of exposure.
There are four main steps involved in risk assessment. Those
steps are (1) hazard identification, (2) hazard assessment, (3)
exposure assessment, and (4) risk characterization. During the
hazard identification stage of a risk assessment, toxicolological,
biological, epidemiological, and chemical data is examined to
determine how toxic a substance is and what effects if will have
on health. The hazard identification of carcinogens is difficult
because the effects of certain carcinogens might not be seen for
many years after the exposure (Phalen & Phalen, 2013). There
are several different classification systems for carcinogens. One
main system, used by the EPA, divides carcinogens into seven
categories. Following is the general classification system:

3. •human carcinogen,
•probable human carcinogen,
•possible human carcinogen,
•not classifiable as to human carcinogenicity, and
•evidence of non-carcinogenicity in humans (Phalen & Phalen,
2013).
After analyzing the hazards associated with a pollutant, the
hazard assessment stage begins. Phalen & Phalen (2013)
identify two main goals of a hazard assessment: (1) to establish
a dose-response relationship and (2) to define an acceptable
exposure threshold or dose. There are both non-cancer and
cancer processes. During a non-cancer assessment, a level is
determined below which it is unlikely that health effects will
occur. In a cancer assessment, however, it is generally assumed
that there is no safe level of exposure. The EPA’s goal is to
reduce cancer risk to less than one in a million per year (Phalen
& Phalen, 2013).
The next step in the risk assessment is the exposure assessment.
After the completion of the hazard identification and the hazard
assessment, the relative toxicity and the acceptable exposure
level has been established. Now, an estimate of the population
exposure must be made. There are a variety of potential
pollutant sources, some of which we have discussed in previous
units (stationary sources, point sources, non-point sources,
mobile sources, etc.). In addition to identifying the potential
sources of community exposure, the routes of exposure must
also be identified. Inhalation is the major route of exposure for
air pollutants. However, particles may also deposit on soil or in
waterways. The pollutant can then be ingested when we eat or
drink. These exposures can be measured through environmental
monitoring, personal monitoring, historical exposure records, or
mathematical models (Phalen & Phalen, 2013). For example,
Hart et al. (2009) studied the association between the incidence
of rheumatoid arthritis and the exposure to traffic pollution. To
assess the subject’s exposure, the distance to a road was

4. analyzed. In this particular study, a correlation between traffic
pollution exposure and rheumatoid arthritis was found.
Lastly, during the risk characterization, the information
collected in the first three steps of the risk assessment (hazard
identification, hazard assessment, and exposure assessment) can
be analyzed to determine the overall risk of exposure to the
pollutant. When the exposure concentration is divided by the
acceptable threshold (if they are in the same unit of
measurement), the hazard quotient is calculated. A quotient
greater than one indicates that exposure exceeds the acceptable
level, and a quotient less than one indicates that the exposure is
below the acceptable level.
There are many uncertainties in the risk assessment process, but
it provides a process by which regulators can analyze the
available data about the toxicity of a pollutant and combine that
information with exposure levels to determine whether or not
the public health is being protected. However, communicating
the meaning of the calculated risk to the public can be a
difficult task. Humans often inaccurately over- or underestimate
risks and make decisions about which risks to take based on
emotion rather than data. Phalen & Phalen (2013) suggest
several techniques for overcoming this communication barrier,
including avoiding appeals to emotion, comparing alternative
technologies, and making comparisons to other risks.
References
Hart, J. E., Laden, F., Puett, R. C., Costenbader, K. H., &
Karlson, E. W. (2009). Exposure to traffic pollution and
increased risk of rheumatoid arthritis. Environmental Health
Perspectives, 117(7).
Phalen, R. F., & Phalen, R. N. (2013). Introduction to air
pollution science: A public health perspective. Burlington, MA:
Jones & Bartlett Learning.

5. Additional Required Reading
See attachment
UnitVIIReadingAssignment_GuidanceforRisk