060201abA Drainage And Venting Systems: Part A Flashcards
What is the limit of directional change in the trap arm before the fixtures vent must be connected
135 degrees
What is the maximum a trap arm fall/ grade before it connects to a vent
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)
What is the minimum length of a trap arm?
Double the pipe diameter
What special allowance for trap arms are water closets given
Extra 90 degrees of change for 225 degrees
How much change vertically and horizontally do water closets get
1 metre vertically
3 metres horizontally
What spots are clean out mandatory
-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
Where can a Tee wye be used
Only used for vents or vertically on a drain where it connects to a vent
What fitting can’t be used for connection of two back outlet water closets in a back-to-back installation
Double tee wye
Is a double tee wye permitted with back to back or side to side lavs ?
Yes
If you use a double tee wye to connect two urinals where does the clean out go ?
Ontop
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
1.5m
What size floor drains are considered emergency fixtures
3” or bigger
How far can a 3” floor drain run before a vent connection
12 feet at 1/4 inch per foot
Minimum trap arm for an un-vented floor drain
18”
What type of backwater valve is not allowed
A Normally closed valve (N/C )
Every building in which plumbing is installed needs one main vent at least what size
3”
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.
Individual vents
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. 
Dual vents
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
Flat vent 
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 
Branch vents
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
Stack vent
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
Continuous vent 
The horizontal portion of a flat vent installed below flood level rim of a fixture must have what
A clean out
When a vent connects to another vent pipe, it must connect above what the fixtures other vent protects
It must connect above flood level rim
