Tradesman Drainlayer Exam Practice
questions n correct answers already
passed
Explain the purpose of a neutralizing tap - correct answer ✔✔ To treat corrosive waste before
allowing it to be discharged into an outfall
Give seven examples of industrial locations where a neutralizing trap would be required -
correct answer ✔✔ Scientific laboratories. Photographic laboratories. Printers. Battery plants.
Electroplaters. Tanneries. Hospitals.
A section of drain has begun to regularly block. Give six possible causes of this. - correct answer
✔✔ Tree roots. Penetrations. Backfall. Collapse. Fats. Foreign object.
Describe the process that occurs in a septic tank's aerated chamber - correct answer ✔✔ Air
introduced into the chamber so that aerobic bacteria work more efficiently.
Give five factors that contribute to stratification/layering in a septic tank. - correct answer ✔✔
Heavier solids sink while lighter liquids float. Differing density of components. Input flow rate.
Retention time. Tank volume.
Name the THREE layers or zones that can be found in a septic tank. - correct answer ✔✔ Scum.
Liquid. Sludge.
Describe the process of transpiration in relation to an effluent disposal system. - correct answer
✔✔ Plants absorb liquid through the roots and then the liquid is released through the leaves.
, Give four reasons why surface water should not be disposed of through a septic tank system. -
correct answer ✔✔ Overloads the tank. Flushes the sewage through to the effluent system.
Flooding the effluent disposal field. Stirs up layers in the tank.
List eight items that should not be flushed into an on-site sewage treatment system because
they would disrupt the bacteria growth within it. - correct answer ✔✔ Grease. Bleaches.
Disinfectants. Paint. Paint thinners. Herbicides. Oils (automotive products). Food scraps.
Give two reasons why septic tanks are buried in the ground. - correct answer ✔✔ To limit
temperature variations in the tank. To provide fall for gravity fed tanks.
State the purpose of an access point on a foul water drainage system. - correct answer ✔✔ To
provide access for inspection or cleaning or maintenance.
Give four precautions that should be undertaken to ensure that people do not fall into an open
excavation during the hours of darkness. - correct answer ✔✔ Provide lights. Provide barriers.
Cover with a steel sheet. Temporarily backfill.
Name nine different methods for jointing two lengths of drainage pipe. - correct answer ✔✔
Rubber ring. Solvent cement. Electrofusion. Rubber sleeve. Bolted gland. Epoxy resin. Cement
mortar. Silver brazing. Threading.
Give six unsafe conditions that may need to be checked. - correct answer ✔✔ Gases. Flooding.
Temperature. Dust. Suitable exit strategy. Stability of walls.
When working in a trench, there is a danger from toxic gases. Explain two reasons why some
toxic gases may accumulate in the trench. - correct answer ✔✔ They are heavier than air. There
is no air movement.
Which of the following best describes the term erosion? - correct answer ✔✔ Wear
questions n correct answers already
passed
Explain the purpose of a neutralizing tap - correct answer ✔✔ To treat corrosive waste before
allowing it to be discharged into an outfall
Give seven examples of industrial locations where a neutralizing trap would be required -
correct answer ✔✔ Scientific laboratories. Photographic laboratories. Printers. Battery plants.
Electroplaters. Tanneries. Hospitals.
A section of drain has begun to regularly block. Give six possible causes of this. - correct answer
✔✔ Tree roots. Penetrations. Backfall. Collapse. Fats. Foreign object.
Describe the process that occurs in a septic tank's aerated chamber - correct answer ✔✔ Air
introduced into the chamber so that aerobic bacteria work more efficiently.
Give five factors that contribute to stratification/layering in a septic tank. - correct answer ✔✔
Heavier solids sink while lighter liquids float. Differing density of components. Input flow rate.
Retention time. Tank volume.
Name the THREE layers or zones that can be found in a septic tank. - correct answer ✔✔ Scum.
Liquid. Sludge.
Describe the process of transpiration in relation to an effluent disposal system. - correct answer
✔✔ Plants absorb liquid through the roots and then the liquid is released through the leaves.
, Give four reasons why surface water should not be disposed of through a septic tank system. -
correct answer ✔✔ Overloads the tank. Flushes the sewage through to the effluent system.
Flooding the effluent disposal field. Stirs up layers in the tank.
List eight items that should not be flushed into an on-site sewage treatment system because
they would disrupt the bacteria growth within it. - correct answer ✔✔ Grease. Bleaches.
Disinfectants. Paint. Paint thinners. Herbicides. Oils (automotive products). Food scraps.
Give two reasons why septic tanks are buried in the ground. - correct answer ✔✔ To limit
temperature variations in the tank. To provide fall for gravity fed tanks.
State the purpose of an access point on a foul water drainage system. - correct answer ✔✔ To
provide access for inspection or cleaning or maintenance.
Give four precautions that should be undertaken to ensure that people do not fall into an open
excavation during the hours of darkness. - correct answer ✔✔ Provide lights. Provide barriers.
Cover with a steel sheet. Temporarily backfill.
Name nine different methods for jointing two lengths of drainage pipe. - correct answer ✔✔
Rubber ring. Solvent cement. Electrofusion. Rubber sleeve. Bolted gland. Epoxy resin. Cement
mortar. Silver brazing. Threading.
Give six unsafe conditions that may need to be checked. - correct answer ✔✔ Gases. Flooding.
Temperature. Dust. Suitable exit strategy. Stability of walls.
When working in a trench, there is a danger from toxic gases. Explain two reasons why some
toxic gases may accumulate in the trench. - correct answer ✔✔ They are heavier than air. There
is no air movement.
Which of the following best describes the term erosion? - correct answer ✔✔ Wear
