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Mississippi Individual Onsite Wastewater Installer
Licensing Exam QUESTIONS AND VERIFIED ANSWERS
WITH RATIONALES JUST RELEASED
Mississippi Individual Onsite Wastewater Installer Licensing Exam
COVERAGE (Most Frequently Tested Areas)
Mississippi Onsite Wastewater Laws, Regulations & Certification Requirements (Core Exam Area); Soil
Evaluation & Site Assessment; Septic Tank Design, Installation & Operation; Absorption Fields,
Drainfields & Effluent Disposal; System Design & Sizing Calculations; Installation Standards &
Construction Practices; Pumps, Dosing Systems & Advanced Treatment Components; Troubleshooting,
Repairs & System Failure Analysis; Public Health & Environmental Protection; Safety Procedures &
Excavation Safety; Inspections, Documentation & Professional Responsibilities.
1. Under the Mississippi Individual On-Site Wastewater Disposal System Law, what is the minimum
passing score required on the closed-book examination for a person to become a Certified Installer?
A) 65%
B) 70%
C) 75%
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D) 80%
Answer: D
Rationale: Mississippi regulations require that an applicant must achieve a score of 80% or better on the
closed-book examination to demonstrate their knowledge and comprehension of the Individual On-site
Wastewater Disposal System Regulations .
2. According to Mississippi State Department of Health (MSDH) regulations, which of the following is the
correct certification renewal cycle for a Certified Installer?
A) Every 1 year
B) Every 2 years
C) Every 3 years
D) Every 5 years
Answer: C
Rationale: MSDH regulations stipulate that the department shall provide for the renewal of installer
certifications once every three (3) years .
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3. A probationary certified installer in Mississippi must successfully install a specified number of
compliant systems before being granted full certification. What is this required number?
A) One
B) Two
C) Three
D) Five
Answer: C
Rationale: A probationary installer must successfully install three Individual On-site Wastewater
Disposal Systems that are inspected and found without deficiencies by the Division before full
certification is granted .
4. What is the minimum general business liability insurance coverage required by Mississippi law for a
certified installer, per occurrence and in total aggregate?
A) $25,000 per occurrence and $50,000 aggregate
B) $50,000 per occurrence and $100,000 aggregate
C) $100,000 per occurrence and $200,000 aggregate
D) $150,000 per occurrence and $300,000 aggregate
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Answer: B
Rationale: Mississippi Code requires that an installer must provide proof of having a valid general
business liability insurance policy in effect with liability limits of at least Fifty Thousand Dollars
($50,000.00) per occurrence and at least One Hundred Thousand Dollars ($100,000.00) in total
aggregate amount .
5. The purpose of a septic tank in an onsite wastewater system is to separate solids from liquids. Which
component of the system is primarily responsible for this initial separation?
A) Distribution box
B) Effluent filter
C) Septic tank
D) Drainfield
Answer: C
Rationale: A septic tank functions as a settling chamber where solids settle to the bottom (sludge) and
lighter solids (scum) float to the top, separating wastewater into solid and liquid fractions .
Mississippi Individual Onsite Wastewater Installer
Licensing Exam QUESTIONS AND VERIFIED ANSWERS
WITH RATIONALES JUST RELEASED
Mississippi Individual Onsite Wastewater Installer Licensing Exam
COVERAGE (Most Frequently Tested Areas)
Mississippi Onsite Wastewater Laws, Regulations & Certification Requirements (Core Exam Area); Soil
Evaluation & Site Assessment; Septic Tank Design, Installation & Operation; Absorption Fields,
Drainfields & Effluent Disposal; System Design & Sizing Calculations; Installation Standards &
Construction Practices; Pumps, Dosing Systems & Advanced Treatment Components; Troubleshooting,
Repairs & System Failure Analysis; Public Health & Environmental Protection; Safety Procedures &
Excavation Safety; Inspections, Documentation & Professional Responsibilities.
1. Under the Mississippi Individual On-Site Wastewater Disposal System Law, what is the minimum
passing score required on the closed-book examination for a person to become a Certified Installer?
A) 65%
B) 70%
C) 75%
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D) 80%
Answer: D
Rationale: Mississippi regulations require that an applicant must achieve a score of 80% or better on the
closed-book examination to demonstrate their knowledge and comprehension of the Individual On-site
Wastewater Disposal System Regulations .
2. According to Mississippi State Department of Health (MSDH) regulations, which of the following is the
correct certification renewal cycle for a Certified Installer?
A) Every 1 year
B) Every 2 years
C) Every 3 years
D) Every 5 years
Answer: C
Rationale: MSDH regulations stipulate that the department shall provide for the renewal of installer
certifications once every three (3) years .
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3. A probationary certified installer in Mississippi must successfully install a specified number of
compliant systems before being granted full certification. What is this required number?
A) One
B) Two
C) Three
D) Five
Answer: C
Rationale: A probationary installer must successfully install three Individual On-site Wastewater
Disposal Systems that are inspected and found without deficiencies by the Division before full
certification is granted .
4. What is the minimum general business liability insurance coverage required by Mississippi law for a
certified installer, per occurrence and in total aggregate?
A) $25,000 per occurrence and $50,000 aggregate
B) $50,000 per occurrence and $100,000 aggregate
C) $100,000 per occurrence and $200,000 aggregate
D) $150,000 per occurrence and $300,000 aggregate
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Answer: B
Rationale: Mississippi Code requires that an installer must provide proof of having a valid general
business liability insurance policy in effect with liability limits of at least Fifty Thousand Dollars
($50,000.00) per occurrence and at least One Hundred Thousand Dollars ($100,000.00) in total
aggregate amount .
5. The purpose of a septic tank in an onsite wastewater system is to separate solids from liquids. Which
component of the system is primarily responsible for this initial separation?
A) Distribution box
B) Effluent filter
C) Septic tank
D) Drainfield
Answer: C
Rationale: A septic tank functions as a settling chamber where solids settle to the bottom (sludge) and
lighter solids (scum) float to the top, separating wastewater into solid and liquid fractions .
