REHS EXAM 2025 QUESTIONS AND
ANSWERS
1. A factor or agent which increases the risk of cancer is known as a
a. teratogen
b. mutagen
c. carcinogen
d. fomite - ANS carcinogen
2. The four major causes of death among all age groups of Americans include all of the
following
except.
a. homicide
b. accidents
c. malignant neoplasms
d. heart disease - ANS homicide
3. In recent years, the largest number of rabies cases were associated with
a. skunks
b. bats
c. dogs
d. raccons. - ANS skunks
4. Asbestosis is caused by fine silicate fibers retained in the
a. kidneys
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,b. lungs
c. colon
d. abdomen - ANS lungs
5. An illness due to a specific infectious agent or its toxic product which is transmitted from a
reservoir to a susceptible host either directly or indirectly is called
a. an infectious disease
b. a communicable disease
c. a genetic disease
d. a noncommunicable disease - ANS a communicable disease
6. Rocky mountain spotted fever is spread by
a. flies
b. spiders
c. cockroaches
d. ticks - ANS ticks
7. Mycotoxins are poisonous chemicals produced by
a. bacteria
b. vertebrates
c. viruses
d. fungi - ANS fungi
8. The study of the occurrence, frequency, and distribution of disease is
a. entomology
b. biology
c. endocrinology
d. epidemiology - ANS epidemiology
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,9. Which of the following organisms are most resistant to unfavorable environmental
conditions and indicate
past or possibly intermittent pollution?
a. fecal streptococci
b. escherichia coli
c. aerobacter aerogenes
d. clostridium sporulates - ANS clostridium sporulates
10. Engineering controls are
a. controls that isolate or remove hazards from the work place
b. less effective than good training
c. the last option that should be considered
d. less effective than personal protection processes - ANS controls that isolate or remove
hazards from the workplace
11. Which of the following is not considered a satisfactory solution to the problem of chemical
contamination in
Well systems?
a. abandoning the well
b. boiling the water
c. building a new, properly constructed, drilled well - ANS boiling the water
12. Which of the following chemicals is most widely used to destroy microorganisms?
a. chlorine
b. copper sulfate
c. chloramine
d. hydrogen sulfate - ANS chlorine
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, 13. Which of the following is not a practical method for removal of cadmium?
a. ion exchange
b. lime softening
c. reverse osmosis
d. iron coagulation - ANS reverse osmosis
14. Which of the following is not a commonly accepted method of device to prevent
backsiphonage?
a. vacuum breakers
b. cross-connections
c. air gap separation
d. back pressure units - ANS cross-connections
15. This substance is the first product of the decomposition of organic matter. Its presence in
water usually
Indicates "fresh pollution" of sanitary significance. What is it?
a. ammonia
b. sugar
c. carbon dioxide
d. hydrogen sulfide - ANS ammonia
16. One of the most common reasons for the contamination of wells drilled through rock, clay,
or hardpan is
a. seepage of pollutants through soil
b. failure to seal well casings properly
c. porosity of the rock
d. use of inferior quality well casings - ANS failure to seal well casings properly
17. In emergencies, small quantities of water can be disinfected by boiling or using
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ANSWERS
1. A factor or agent which increases the risk of cancer is known as a
a. teratogen
b. mutagen
c. carcinogen
d. fomite - ANS carcinogen
2. The four major causes of death among all age groups of Americans include all of the
following
except.
a. homicide
b. accidents
c. malignant neoplasms
d. heart disease - ANS homicide
3. In recent years, the largest number of rabies cases were associated with
a. skunks
b. bats
c. dogs
d. raccons. - ANS skunks
4. Asbestosis is caused by fine silicate fibers retained in the
a. kidneys
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,b. lungs
c. colon
d. abdomen - ANS lungs
5. An illness due to a specific infectious agent or its toxic product which is transmitted from a
reservoir to a susceptible host either directly or indirectly is called
a. an infectious disease
b. a communicable disease
c. a genetic disease
d. a noncommunicable disease - ANS a communicable disease
6. Rocky mountain spotted fever is spread by
a. flies
b. spiders
c. cockroaches
d. ticks - ANS ticks
7. Mycotoxins are poisonous chemicals produced by
a. bacteria
b. vertebrates
c. viruses
d. fungi - ANS fungi
8. The study of the occurrence, frequency, and distribution of disease is
a. entomology
b. biology
c. endocrinology
d. epidemiology - ANS epidemiology
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,9. Which of the following organisms are most resistant to unfavorable environmental
conditions and indicate
past or possibly intermittent pollution?
a. fecal streptococci
b. escherichia coli
c. aerobacter aerogenes
d. clostridium sporulates - ANS clostridium sporulates
10. Engineering controls are
a. controls that isolate or remove hazards from the work place
b. less effective than good training
c. the last option that should be considered
d. less effective than personal protection processes - ANS controls that isolate or remove
hazards from the workplace
11. Which of the following is not considered a satisfactory solution to the problem of chemical
contamination in
Well systems?
a. abandoning the well
b. boiling the water
c. building a new, properly constructed, drilled well - ANS boiling the water
12. Which of the following chemicals is most widely used to destroy microorganisms?
a. chlorine
b. copper sulfate
c. chloramine
d. hydrogen sulfate - ANS chlorine
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, 13. Which of the following is not a practical method for removal of cadmium?
a. ion exchange
b. lime softening
c. reverse osmosis
d. iron coagulation - ANS reverse osmosis
14. Which of the following is not a commonly accepted method of device to prevent
backsiphonage?
a. vacuum breakers
b. cross-connections
c. air gap separation
d. back pressure units - ANS cross-connections
15. This substance is the first product of the decomposition of organic matter. Its presence in
water usually
Indicates "fresh pollution" of sanitary significance. What is it?
a. ammonia
b. sugar
c. carbon dioxide
d. hydrogen sulfide - ANS ammonia
16. One of the most common reasons for the contamination of wells drilled through rock, clay,
or hardpan is
a. seepage of pollutants through soil
b. failure to seal well casings properly
c. porosity of the rock
d. use of inferior quality well casings - ANS failure to seal well casings properly
17. In emergencies, small quantities of water can be disinfected by boiling or using
COPYRIGHT © 2025 FYNDLAY ALL RIGHTS RESERVED 4
