ASSE 12080-legionella Exam Questions
with Complete Answers 2026 Updated.
In the absence of stagnation, biofilm, and other complexities, Legionella pneumophila will be
dormant (not multiply) in water below - Answer 20°C (68°F)
Systems or devices that can harbor and transmit Legionella and have been implicated in cases of
Legionnaires' disease include all but which of the following: - Answer natural gas piping
According to the [US] Centers for Disease Control and Prevention, approximately what
percentage of Legionnaires' disease cases among hospital patients are diagnosed? - Answer
10%
Which of the following is not an essential component of water management plans developed
for the purpose of controlling Legionella? - Answer Average annual temperature of the water
in the fire protection system
Primary factors that affect Legionella growth include all but which of the following: - Answer
Pressure
Studies have shown that a Legionella infection can be contracted by: - Answer Inhaling or
aspirating into the lungs Legionella bacteria transmitted from water
A(n) ______________ approach to preventing Legionnaires' disease (LD) is to test and disinfect
water systems only after a facility-acquired case of LD is identified rather than managing water
systems to prevent cases. A(n) ________________ approach is to manage water systems to
minimize Legionella. - Answer reactive; proactive
As biofilm grows, fragments of it break off and flow into the water, delivering potentially high
levels of Legionella to faucets, showers, and drinking fountains. - Answer True
The [US] CDC defines an outbreak (or cluster) of Legionnaires' disease as ___ or more cases
associated with the same possible source during a ___ month period. For cooling towers, the
duration of time considered for defining an outbreak could be ____________. - Answer 2; 12;
shorter
Only smokers or persons who are immunocompromised or elderly are at risk of contracting
Legionnaires' disease and of dying from it. - Answer False
,In the absence of stagnation, biofilm, and other complexities, Legionella pneumophila will die
within about 32 minutes in water at - Answer 60°C (140°F)
Compared to Legionella pneumophila, the optimum temperature range for multiplication is
____________ for Pseudomonas aeruginosa and slightly ____________ for Mycobacteria avium
- Answer lower; wider
Per the [US] CDC, to diagnose Legionnaires' disease, sputum for culture should ideally be
obtained __________ antibiotic treatment. - Answer before
Which of the following best describes Legionella? - Answer bacteria that typically live inside
biofilm or amoebae
The scientific community worldwide largely agrees that the best strategy for preventing
Legionnaires' disease, with current technology, is to: - Answer Manage building water systems
to minimize Legionella bacteria
Pontiac fever is a highly contagious illness with a death rate of nearly 50%. - Answer false
Legionellosis is any illness caused by Legionella bacteria. The two most common types are
Pontiac fever and Legionnaires' disease. - Answer true
The US Centers for Medicare and Medicaid Services (CMS) memorandum QSO-17-30-
Hospitals/CAHs/NHs requires that hospitals test their water systems for Legionella? - Answer
False
Per the memorandum referencing "QSO-17-30-Hospitals/CAHs/NHs," the US Department of
Health & Human Services, Centers for Medicare and Medicaid Services (CMS), requires that all
but which of the following facility types implement a water management program to reduce the
risk of Legionella and other opportunistic pathogens: - Answer outpatient clinics
Guidelines typically provide practices, instructions, or procedures that are - Answer
recommended
It takes ___ day(s) to get results from a Legionella urinary antigen test and ___ day(s) to get
results from a sputum Legionella culture test. - Answer < 1; > 5
In the absence of stagnation, biofilm, and other complexities, Legionella pneumophila will
survive but not multiply in water at - Answer 50°C (122°F)
, Many outbreaks of Legionnaires' disease that have been reported in scientific literature were
shown to be associated with which of the following? - Answer Construction projects or water
main work
The Legionella urinary antigen test can detect: - Answer only Legionella pneumophila
serogroup 1
Per the [US] CDC, which Legionella diagnostic test allows clinical and environmental isolates to
be compared, to help investigators identify where exposure occurred? - Answer Sputum
culture
Biofilms that form on valves and fittings and pipe walls can not only feed Legionella bacteria but
also protect them from disinfectants. - Answer True
Per the [US] CDC, if indications warrant testing a patient for Legionnaires' disease, it is best
practice to obtain the following: - Answer both sputum for culture and urine for a urinary
antigen test concurrently
Which statement is true? - Answer Most cases of Legionnaires' disease are not diagnosed and
many cases that are diagnosed result in death or long term disabilities.
Evidence examined by the CDC after discovering Legionella indicates the bacteria had not
caused illness prior to the outbreak in 1976. - Answer False
Legionnaires' disease is typically treated with: - Answer Antibiotics
There are more than 70 Legionella species, less than half of which have been linked to
Legionnaires' disease. - Answer 70
Each Legionella control measure must be: - Answer monitored to determine whether it is
performed to a designated standard (control limit)
All but which of the following are required for a water management program team per ASHRAE
188? - Answer availability 24/7/365
A Legionella hazard analysis notes which water systems identified in the facility survey present a
significant potential for Legionella growth and transmission, and locations at which Legionella
control measures can and should be applied. The hazard analysis does not typically vary from
one system to another of the same type. - Answer True
with Complete Answers 2026 Updated.
In the absence of stagnation, biofilm, and other complexities, Legionella pneumophila will be
dormant (not multiply) in water below - Answer 20°C (68°F)
Systems or devices that can harbor and transmit Legionella and have been implicated in cases of
Legionnaires' disease include all but which of the following: - Answer natural gas piping
According to the [US] Centers for Disease Control and Prevention, approximately what
percentage of Legionnaires' disease cases among hospital patients are diagnosed? - Answer
10%
Which of the following is not an essential component of water management plans developed
for the purpose of controlling Legionella? - Answer Average annual temperature of the water
in the fire protection system
Primary factors that affect Legionella growth include all but which of the following: - Answer
Pressure
Studies have shown that a Legionella infection can be contracted by: - Answer Inhaling or
aspirating into the lungs Legionella bacteria transmitted from water
A(n) ______________ approach to preventing Legionnaires' disease (LD) is to test and disinfect
water systems only after a facility-acquired case of LD is identified rather than managing water
systems to prevent cases. A(n) ________________ approach is to manage water systems to
minimize Legionella. - Answer reactive; proactive
As biofilm grows, fragments of it break off and flow into the water, delivering potentially high
levels of Legionella to faucets, showers, and drinking fountains. - Answer True
The [US] CDC defines an outbreak (or cluster) of Legionnaires' disease as ___ or more cases
associated with the same possible source during a ___ month period. For cooling towers, the
duration of time considered for defining an outbreak could be ____________. - Answer 2; 12;
shorter
Only smokers or persons who are immunocompromised or elderly are at risk of contracting
Legionnaires' disease and of dying from it. - Answer False
,In the absence of stagnation, biofilm, and other complexities, Legionella pneumophila will die
within about 32 minutes in water at - Answer 60°C (140°F)
Compared to Legionella pneumophila, the optimum temperature range for multiplication is
____________ for Pseudomonas aeruginosa and slightly ____________ for Mycobacteria avium
- Answer lower; wider
Per the [US] CDC, to diagnose Legionnaires' disease, sputum for culture should ideally be
obtained __________ antibiotic treatment. - Answer before
Which of the following best describes Legionella? - Answer bacteria that typically live inside
biofilm or amoebae
The scientific community worldwide largely agrees that the best strategy for preventing
Legionnaires' disease, with current technology, is to: - Answer Manage building water systems
to minimize Legionella bacteria
Pontiac fever is a highly contagious illness with a death rate of nearly 50%. - Answer false
Legionellosis is any illness caused by Legionella bacteria. The two most common types are
Pontiac fever and Legionnaires' disease. - Answer true
The US Centers for Medicare and Medicaid Services (CMS) memorandum QSO-17-30-
Hospitals/CAHs/NHs requires that hospitals test their water systems for Legionella? - Answer
False
Per the memorandum referencing "QSO-17-30-Hospitals/CAHs/NHs," the US Department of
Health & Human Services, Centers for Medicare and Medicaid Services (CMS), requires that all
but which of the following facility types implement a water management program to reduce the
risk of Legionella and other opportunistic pathogens: - Answer outpatient clinics
Guidelines typically provide practices, instructions, or procedures that are - Answer
recommended
It takes ___ day(s) to get results from a Legionella urinary antigen test and ___ day(s) to get
results from a sputum Legionella culture test. - Answer < 1; > 5
In the absence of stagnation, biofilm, and other complexities, Legionella pneumophila will
survive but not multiply in water at - Answer 50°C (122°F)
, Many outbreaks of Legionnaires' disease that have been reported in scientific literature were
shown to be associated with which of the following? - Answer Construction projects or water
main work
The Legionella urinary antigen test can detect: - Answer only Legionella pneumophila
serogroup 1
Per the [US] CDC, which Legionella diagnostic test allows clinical and environmental isolates to
be compared, to help investigators identify where exposure occurred? - Answer Sputum
culture
Biofilms that form on valves and fittings and pipe walls can not only feed Legionella bacteria but
also protect them from disinfectants. - Answer True
Per the [US] CDC, if indications warrant testing a patient for Legionnaires' disease, it is best
practice to obtain the following: - Answer both sputum for culture and urine for a urinary
antigen test concurrently
Which statement is true? - Answer Most cases of Legionnaires' disease are not diagnosed and
many cases that are diagnosed result in death or long term disabilities.
Evidence examined by the CDC after discovering Legionella indicates the bacteria had not
caused illness prior to the outbreak in 1976. - Answer False
Legionnaires' disease is typically treated with: - Answer Antibiotics
There are more than 70 Legionella species, less than half of which have been linked to
Legionnaires' disease. - Answer 70
Each Legionella control measure must be: - Answer monitored to determine whether it is
performed to a designated standard (control limit)
All but which of the following are required for a water management program team per ASHRAE
188? - Answer availability 24/7/365
A Legionella hazard analysis notes which water systems identified in the facility survey present a
significant potential for Legionella growth and transmission, and locations at which Legionella
control measures can and should be applied. The hazard analysis does not typically vary from
one system to another of the same type. - Answer True
