060201abA Drainage And Venting Systems: Part A

Question 1

What is the limit of directional change in the trap arm before the fixtures vent must be connected

Answer 1

135 degrees

Question 2

What is the maximum a trap arm fall/ grade before it connects to a vent

Answer 2

Cannot drop larger than it’s inside diameter- ex 1 1/2” pipe cannot drop/ grade more than 1 1/2” ( 6ft with 1/4” per ft)

Question 3

What is the minimum length of a trap arm?

Answer 3

Double the pipe diameter

Question 4

What special allowance for trap arms are water closets given

Answer 4

Extra 90 degrees of change for 225 degrees

Question 5

How much change vertically and horizontally do water closets get

Answer 5

1 metre vertically
3 metres horizontally

Question 6

What spots are clean out mandatory

Answer 6

-where the building drain enters a building
-the base of every stack
-directly above every running trap
-in a location permitting the cleaning of any interceptor

Question 7

Where can a Tee wye be used

Answer 7

Only used for vents or vertically on a drain where it connects to a vent

Question 8

What fitting can’t be used for connection of two back outlet water closets in a back-to-back installation

Answer 8

Double tee wye

Question 9

Is a double tee wye permitted with back to back or side to side lavs ?

Answer 9

Yes

Question 10

If you use a double tee wye to connect two urinals where does the clean out go ?

Answer 10

Ontop

Question 11

A horizontal drainage pipe must not have a wye taken off how far from a vertical stack if that stack receives 30 or more fixture units or receives sewage from 2 or more stories above

Answer 11

1.5m

Question 12

What size floor drains are considered emergency fixtures

Answer 12

3” or bigger

Question 13

How far can a 3” floor drain run before a vent connection

Answer 13

12 feet at 1/4 inch per foot

Question 14

Minimum trap arm for an un-vented floor drain

Answer 14

18”

Question 15

What type of backwater valve is not allowed

Answer 15

A Normally closed valve (N/C )

Question 16

Every building in which plumbing is installed needs one main vent at least what size

Answer 16

3”

Question 17

Every fixture has its own vent pipe, installed to protect the water seal in the fixture trap. However, this arrangement is not practical, nor is it desirable due to the cost of material and labor.

Answer 17

Individual vents

Question 18

A method of venting in which two fixture trap seals are protected from positive or negative pressures. Using only one vent pipe. This is the simplest form of group venting a form of group venting is when one vent serves more than one trap. 

Answer 18

Dual vents

Question 19

Individual vent installed with some portion of the vent usually near the fixture running horizontally below flood level rim a flat vent is often used for fixtures, like kitchen sinks, basins, and bathtubs

Answer 19

Flat vent 

Question 20

A method of venting, connecting small Vents from fixtures into a common vent pipe for ease and economy of installation the branch vent pipe must be large enough to vent the entire load of fixtures, venting through it branch venting allows you to avoid multiple floor wall and roof penetrations 

Answer 20

Branch vents

Question 21

A cent pipe that connects the top of a stack of vertical sanitary drainage pipe that penetrates through more than one story of a building to other outside air or to ventaa header

Answer 21

Stack vent

Question 22

The type that is an extension of a vertical section of a branch or fixture drain the upper end of every horizontally wet vented branch terminates into this vent

Answer 22

Continuous vent 

Question 23

The horizontal portion of a flat vent installed below flood level rim of a fixture must have what

Answer 23

A clean out

Question 24

When a vent connects to another vent pipe, it must connect above what the fixtures other vent protects

Answer 24

It must connect above flood level rim

Question 25

Can vertical wet vents terminate into a continuous vent if the vertical section of piping does not pass through one complete story

Answer 25

Yes