306A National Plumbing Code of Canada 1

Question 1

What is the minimum size of a building drain serving a single water closet according to the National Plumbing Code of Canada?

Accepted Answer

3 inch

Answer

The National Plumbing Code of Canada specifies a minimum 3-inch diameter for a building drain serving a water closet to ensure adequate flow and prevent blockages.

Question 2

According to the Code, what is the maximum distance a P-trap can be from the vent connection?

Accepted Answer

1.2 m for 1¼ inch trap

Answer

The Code limits the trap-to-vent distance to 1.2 m for a 1¼-inch trap arm to maintain the trap seal and prevent siphonage.

Question 3

What minimum slope is required for a 4-inch horizontal drainage pipe in the National Plumbing Code of Canada?

Accepted Answer

1 in 50 (2%)

Answer

A 4-inch horizontal drain requires a minimum slope of 1 in 50 (approximately 2%) to maintain self-cleansing velocity and prevent solid deposits.

Question 4

How many fixture units does a standard bathtub have according to the National Plumbing Code of Canada?

Accepted Answer

2 fixture units

Answer

A bathtub is rated at 2 fixture units in the National Plumbing Code of Canada, reflecting its moderate water demand and drainage load.

Question 5

What is the minimum depth of a trap seal required by the National Plumbing Code of Canada?

Accepted Answer

50 mm

Answer

The Code requires a minimum trap seal depth of 50 mm (approximately 2 inches) to prevent sewer gases from entering occupied spaces.

Red Seal Plumber 306A Practice Test

Red Seal Plumber 306A Practice Test

306A National Plumbing Code of Canada 1