BS: Lesson 2 - Water Supply & Drainage Systems Flashcards
What are the 3 types of plumbing systems
supply systems - pressurized system
sanitary system - gravity feed system
storm water system - gravity feed system
In regards to water supply, what are the 4 concerns for water
acidity
hardness
carcinogens
disease
Water that has a pH of 7 is
neutral
In terms of acidity, rain water that falls from the sky is, which one:
- has no acidity
- is slightly acidic
- highly acidic
slightly acidic
In terms of acidity, water with a pH between 7 and 14 is what?
A basic alkaline solution
What happens when rain water mixes with the bi-products of combustion in the air?
It forms sulfuric acid and nitric acid rain
What causes sulfuric acid rain
Rain water mixing with sulfuric acid from combustion air
What causes nitric acid rain
Rain water mixing with nitrogen compounds from combustion air
Why is acid rain a problem
It corrodes metal pipes
In terms of water supply and potability, what process results in “hard water”
Rain water seeping into the ground and disolving minieral like limestone (CaCo3), calcium and/or magnesium.
Does water hardness interfere with the cleaning and lathering capabilities of detergents and soaps
Yes
What four factors effect water pressure
Lift
Friction
Thermal expansion
Static head
In regards to water supply, the presence of bacteria and viruses in water are a result of what
Improper disposal of human and animal waste.
If water pressure from the main is insufficient to supply the upper floors of a building, what can be installed to increase the pressure
downfeed system
pneumatic tank system
tankless system
In regards to a downfeed system, what is the greatest height water can be sucked up
33 feet
Will pushing or sucking water in a downfeed system achieve the greatest height if trying to supply water to upper floors of a building over 3 storys
Pushing - water can be pushed up from below to just about any height
Friction loss is a function of what?
Flow rate and diameter of the pipe.
Valves, tanks and other similar devices.
In regards to hot water heaters and usage, the most cost effective way to conserve energy is to
Insulate the hot water pipes
Arrange the following pipe materials in order of highest to least amount of thermal expansion: copper, PVC, steel, cast iron
PVC - greatest - coefficient of 35
copper - coefficient of 9.8
steel - coefficient of 6.5
cast iron - lowest - coefficient of 5.6
In sanitary drains, what do sanitary vents do
Relieve pressure in the system and break the suction or siphoning action that occurs when water passes down thru the system
When are soil lines and soil stacks referred to as waste lines and waste stacks
when a toilet is added
What is the minimum diameter of a sanitary vent
1-1/4” or half the diameter of the drain it serves; which ever is greater.
Per ANSI A117, what is the minimum size of a HCAP accessible restroom stall
48” wide by 56” deep
At what height is the toilet seat of a HCAP accessible toilet
19”
