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OSSF INSTALLER 1 AND 2 LICENSE ACTUAL
EXAM NEWEST 2025 ACTUAL EXAM COMPLETE
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED
A+|BRAND NEW!!
ANSI - .....ANSWER ...✔✔ American National
Standards Institute
BOD - .....ANSWER ...✔✔ biochemical oxygen
demand, typically expressed in mg/L.
CBOD - .....ANSWER ...✔✔ Carbonaceous
Biochemical Oxygen Demand, expressed in mg/L.
FC - .....ANSWER ...✔✔ Fecal Coliform, expressed in
number of colonies 100/ml.
LOSS - .....ANSWER ...✔✔ large on-site sewage
system
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NSF - .....ANSWER ...✔✔ Nation Sanitation
Foundation International
O&G - .....ANSWER ...✔✔ Oils and Grease,
component of sewage typically originating from food
stuffs (animal fats of vegetable oils) expressed in mg/L.
RS&G - .....ANSWER ...✔✔ Recommended Standards
and Guidance
SSAS - .....ANSWER ...✔✔ a subsurface soil
absorption system
TAC - .....ANSWER ...✔✔ Technical Advisory
Committee established in WAC 247-272A-0400
TN - .....ANSWER ...✔✔ Total Nitrogen, expressed in
mg/L.
TSS - .....ANSWER ...✔✔ Total Suspended Solids. A
measure of the total suspended solids in a given solution,
expressed in mg/L.
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USEPA - .....ANSWER ...✔✔ United States
Environmental Protection Agency
Additive - .....ANSWER ...✔✔ a commercial product
added to an on-site sewage system intended to affect
the performance or aesthetics of an on-site sewage
system
Approved - .....ANSWER ...✔✔ Acceptable to the
authority having jurisdiction. Local health officer or the
department
BED - .....ANSWER ...✔✔ a soil dispersal component
consisting of an excavation with a width greater than 3
feet
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 sewer, individual sewage disposal
system or other point of disposal. It begins two feet
outside the building wall and conveys sewage from the
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building drain to the remaining portions of the on-site
sewage system.
Cesspool - .....ANSWER ...✔✔ a covered hole or pit
for receiving drainage or sewage, as from a house
allowing liquid to seep into the surronding rock or soil
Conforming System - .....ANSWER ...✔✔ an on-site
sewage system of component meeting rules of: New
construction requirements
Approved and installed within previous requirements
Permitted by WAC-246-272A-0420
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.
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.
OSSF INSTALLER 1 AND 2 LICENSE ACTUAL
EXAM NEWEST 2025 ACTUAL EXAM COMPLETE
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED
A+|BRAND NEW!!
ANSI - .....ANSWER ...✔✔ American National
Standards Institute
BOD - .....ANSWER ...✔✔ biochemical oxygen
demand, typically expressed in mg/L.
CBOD - .....ANSWER ...✔✔ Carbonaceous
Biochemical Oxygen Demand, expressed in mg/L.
FC - .....ANSWER ...✔✔ Fecal Coliform, expressed in
number of colonies 100/ml.
LOSS - .....ANSWER ...✔✔ large on-site sewage
system
,2|Page
NSF - .....ANSWER ...✔✔ Nation Sanitation
Foundation International
O&G - .....ANSWER ...✔✔ Oils and Grease,
component of sewage typically originating from food
stuffs (animal fats of vegetable oils) expressed in mg/L.
RS&G - .....ANSWER ...✔✔ Recommended Standards
and Guidance
SSAS - .....ANSWER ...✔✔ a subsurface soil
absorption system
TAC - .....ANSWER ...✔✔ Technical Advisory
Committee established in WAC 247-272A-0400
TN - .....ANSWER ...✔✔ Total Nitrogen, expressed in
mg/L.
TSS - .....ANSWER ...✔✔ Total Suspended Solids. A
measure of the total suspended solids in a given solution,
expressed in mg/L.
,3|Page
USEPA - .....ANSWER ...✔✔ United States
Environmental Protection Agency
Additive - .....ANSWER ...✔✔ a commercial product
added to an on-site sewage system intended to affect
the performance or aesthetics of an on-site sewage
system
Approved - .....ANSWER ...✔✔ Acceptable to the
authority having jurisdiction. Local health officer or the
department
BED - .....ANSWER ...✔✔ a soil dispersal component
consisting of an excavation with a width greater than 3
feet
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 sewer, individual sewage disposal
system or other point of disposal. It begins two feet
outside the building wall and conveys sewage from the
, 4|Page
building drain to the remaining portions of the on-site
sewage system.
Cesspool - .....ANSWER ...✔✔ a covered hole or pit
for receiving drainage or sewage, as from a house
allowing liquid to seep into the surronding rock or soil
Conforming System - .....ANSWER ...✔✔ an on-site
sewage system of component meeting rules of: New
construction requirements
Approved and installed within previous requirements
Permitted by WAC-246-272A-0420
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.
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.
