CHAPTER 3(NPCP)

What is a common reason for prohibiting side-inlet quarter bends in drainage systems?

• A) They are too expensive to manufacture
  
  
  

• B) They do not provide enough slope for proper drainage

• C) They can cause waste backups and clogging

• D) They are only allowed in residential buildings

What is the primary reason for reaming the burred ends of pipes?

• A) To increase water pressure
  
  
  

• B) To prevent turbulence and clogging

• C) To reduce the cost of installation

• D) To strengthen the pipe material

n an interior lot, when a rear building cannot have its own sewer line, under what condition can it connect to the front building's drain?

• A) Only if the front building’s drain size is adequate for both buildings

• B) If the rear building is taller than the front building

• C) Only if a pump system is used

• D) If the rear building has a direct connection to the city sewer

Why are running thread fittings prohibited in drainage systems?

• A) They create weak joints prone to leakage

• B) They are too expensive to install

• C) They allow excessive water pressure

• D) They require specialized tools to install

Which is an approved method for sealing an unused opening in a drainage system?

• A) Covering it with tape

• B) Using a rubber stopper

• C) Permanently plugging or capping it

• D) Leaving it open for ventilation

Which of the following drainage fittings is prohibited?

• A) 45-degree elbow

• B) Double hub fitting in a vertical position

• C) Sanitary tee used in a vertical stack

• D) Neoprene gasket with stainless steel band

What is the required slope for pipes with a diameter less than 102mm?

• A) 5mm/m or 0.5%

• B) 10mm/m or 1%

• C) 20mm/m or 2%

• D) 25mm/m or 2.5%

When using a driven pipe method for installation, how much larger should the drive pipe be compared to the pipe to be laid?

• A) The same size

• B) One pipe size larger

• C) Two pipe sizes larger

• D) Three pipe sizes larger

What is the maximum allowable length of a tunnel used for underground pipe installation?

• A) 1.2 meters

• B) 2.4 meters

• C) 3.0 meters

• D) 5.0 meters

What is the minimum required clear height above a pipe when installing it in a tunnel?

• A) 0.30 meters

• B) 0.45 meters

• C) 0.60 meters

• D) 1.00 meter