Washington State (WOSSA) Septic Installer Practice Exam
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1. ANSI Answer American National Standards Institute
2. BOD Answer biochemical oxygen demand, typically expressed in mg/L.
3. CBOD Answer Carbonaceous Biochemical Oxygen Demand, expressed in mg/L.
4. FC Answer Fecal Coliform, expressed in number of colonies 100/ml.
5. LOSS Answer large on-site sewage system
6. NSF Answer Nation Sanitation Foundation International
7. O&G Answer Oils and Grease, component of sewage typically originating from food stutts (animal fats of
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, vegetable oils) expressed in mg/L.
8. RS&G Answer Recommended Standards and Guidance
9. SSAS Answer a subsurface soil absorption system
10. TAC Answer Technical Advisory Committee established in WAC 247-272A-0400
11. TN Answer Total Nitrogen, expressed in mg/L.
12. TSS Answer Total Suspended Solids. A measure of the total suspended solids in a given solution, expressed in
mg/L.
13. USEPA Answer United States Environmental Protection Agency
14. Additive Answer a commercial product added to an on-site sewage system intended to attect the
performance or aesthetics of an on-site sewage system
15. Approved Answer Acceptable to the authority having jurisdiction. Local health oflcer or the department
16. BED Answer a soil dispersal component consisting of an excavation with a width greater than 3 feet
17. Building Sewer Answer that part of the horizontal piping of a drainage system which starts from the end
of the building drain and which receives the discharge of the building drain and conveys it to a public sewer, private
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, sewer, individual sewage disposal system or other point of disposal. It begins two feet outside the building wall and
conveys sewage from the building drain to the remaining portions of the on-site sewage system.
18. Cesspool Answer a covered hole or pit for receiving drainage or sewage, as from a house allowing liquid to see
into
the surronding rock or soil
19. Conforming System Answer an on-site sewage system of component meeting rules of Answer New
construction requirements
Approved and installed within previous requirements
Permitted by WAC-246-272A-0420
20. Cover Material Answer Soil placed over dispersal component, made up of mineral material with no greater
than
10% organic content. Cover may contain organic surface material, an organic landscaper to help reduce and contain
soil erosion.
mailto:https://www.stuvia.com/user/DREAMS
, 21. Cuts and Banks Answer a naturally occurring or artificially formed slope greater than one hundred
percent (forty-five degrees) and extending vertically at least five from the toe of the slope to top of the slope.
22. Department Answer Washington State Department of Health
23. Designer Answer Person who matches site and soil characteristics with approved components
24. Design Flow Answer Means the maximum volume of sewage a residence, structure or other facility is
estimated to generate in a twenty-four hour period. It incorporates both an operating capacity and a surge capacity
for the system during periodic heavy use events. The sizing and design of a on-site sewage system component is based
on the design flow.
25. Development Answer The creation of a residence, structure, facility, subdivision, area, or similar activ
resulting in
the production of sewage.
26. Disinfection Answer The process of destroying pathogens in sewage through the application of chlorination,
ultra-vi- olent light, or ozonation.
27. Distribution Technology Answer any arrangement of equipment and/or material that distributes
mailto:https://www.stuvia.com/user/DREAMS
2026 | Updated Actual Exam with Verified Questions and
Correct Solutions | Expert Verified | Guaranteed Pass |
Latest Update
1. ANSI Answer American National Standards Institute
2. BOD Answer biochemical oxygen demand, typically expressed in mg/L.
3. CBOD Answer Carbonaceous Biochemical Oxygen Demand, expressed in mg/L.
4. FC Answer Fecal Coliform, expressed in number of colonies 100/ml.
5. LOSS Answer large on-site sewage system
6. NSF Answer Nation Sanitation Foundation International
7. O&G Answer Oils and Grease, component of sewage typically originating from food stutts (animal fats of
mailto:https://www.stuvia.com/user/DREAMS
, vegetable oils) expressed in mg/L.
8. RS&G Answer Recommended Standards and Guidance
9. SSAS Answer a subsurface soil absorption system
10. TAC Answer Technical Advisory Committee established in WAC 247-272A-0400
11. TN Answer Total Nitrogen, expressed in mg/L.
12. TSS Answer Total Suspended Solids. A measure of the total suspended solids in a given solution, expressed in
mg/L.
13. USEPA Answer United States Environmental Protection Agency
14. Additive Answer a commercial product added to an on-site sewage system intended to attect the
performance or aesthetics of an on-site sewage system
15. Approved Answer Acceptable to the authority having jurisdiction. Local health oflcer or the department
16. BED Answer a soil dispersal component consisting of an excavation with a width greater than 3 feet
17. Building Sewer Answer that part of the horizontal piping of a drainage system which starts from the end
of the building drain and which receives the discharge of the building drain and conveys it to a public sewer, private
mailto:https://www.stuvia.com/user/DREAMS
, sewer, individual sewage disposal system or other point of disposal. It begins two feet outside the building wall and
conveys sewage from the building drain to the remaining portions of the on-site sewage system.
18. Cesspool Answer a covered hole or pit for receiving drainage or sewage, as from a house allowing liquid to see
into
the surronding rock or soil
19. Conforming System Answer an on-site sewage system of component meeting rules of Answer New
construction requirements
Approved and installed within previous requirements
Permitted by WAC-246-272A-0420
20. Cover Material Answer Soil placed over dispersal component, made up of mineral material with no greater
than
10% organic content. Cover may contain organic surface material, an organic landscaper to help reduce and contain
soil erosion.
mailto:https://www.stuvia.com/user/DREAMS
, 21. Cuts and Banks Answer a naturally occurring or artificially formed slope greater than one hundred
percent (forty-five degrees) and extending vertically at least five from the toe of the slope to top of the slope.
22. Department Answer Washington State Department of Health
23. Designer Answer Person who matches site and soil characteristics with approved components
24. Design Flow Answer Means the maximum volume of sewage a residence, structure or other facility is
estimated to generate in a twenty-four hour period. It incorporates both an operating capacity and a surge capacity
for the system during periodic heavy use events. The sizing and design of a on-site sewage system component is based
on the design flow.
25. Development Answer The creation of a residence, structure, facility, subdivision, area, or similar activ
resulting in
the production of sewage.
26. Disinfection Answer The process of destroying pathogens in sewage through the application of chlorination,
ultra-vi- olent light, or ozonation.
27. Distribution Technology Answer any arrangement of equipment and/or material that distributes
mailto:https://www.stuvia.com/user/DREAMS
