Engineering Utilities 2: Water Systems

• The quiz covers plumbing engineering topics.
• It includes 100 multiple-choice questions.
• The quiz focuses on engineering utilities 2, CE 112.

Water Sources & Supply Systems

• Potable water is suitable for drinking.
• Oil wells are not a water source.
• An aquifer is a water-bearing layer of rock.
• A driven well is constructed by driving a pipe into the ground.
• The recommended minimum depth for a drilled well to avoid contamination is 25 ft.
• Water that runs off the surface into streams and lakes is surface water.
• A water table is the boundary between saturated and unsaturated ground.
• Household taps are included in Level 3 of water supply.
• A cistern is used to store treated potable water.
• A flowing well is drilled into a confined aquifer and rises above the aquifer level.

Fluid Properties & Flow

• The unit weight of water is 62.42 lb/ft³ or 9.81 kN/m³.
• Density is defined as mass per unit volume.
• The specific gravity of a liquid is the ratio of its density to water density.
• Atmospheric pressure at sea level is approximately 760 mm Hg or 101.325 kPa.
• The formula for volumetric flow rate (Q) is Q = V/t.
• Hydrostatic pressure is caused by the height of liquid.
• Water hammer occurs due to sudden stopping of water flow.
• Viscosity defines resistance to flow.
• The velocity of water in a pipe is affected by pipe diameter, fluid viscosity, and pressure difference.
• Bernoulli's Principle states the pressure of a fluid decreases as its velocity increases.

Plumbing Materials

• Lead pipe is not used due to toxicity.
• Brass is commonly used for water supply pipes.
• CPVC is the strongest plastic pipe for high-temperature use.
• ABS pipe is best suited for vent systems.
• Copper pipes are categorized into types K, L, M, and DWV.
• Vitrified clay pipe is mainly used for sewer systems.
• The standard length of a galvanized steel pipe is 6m.
• Clay is commonly used in underground sewer systems.
• HDPE is a pipe commonly used for LPG distribution.
• The primary advantage of CPVC over PVC is higher temperature resistance.

Pipe Fittings & Valves

• An elbow fitting changes the direction of a pipe at a 90-degree angle.
• A reducer fitting decreases pipe size.
• A sanitary tee is designed for drainage systems.
• A cross pipe fitting allows three connections at right angles.
• A union fitting allows easy disconnection of pipes.
• A gate valve stops or allows full flow.
• A globe valve is primarily used for throttling flow.
• A check valve prevents reverse flow.
• An angle valve is commonly used for water closets.
• A ball valve operates by a rotating spherical disc.

Plumbing Fixtures

• A water closet is also called a toilet.
• A waterless urinal uses no water for flushing.
• The primary purpose of a bidet is for personal hygiene.
• The minimum width of a shower stall is 750 mm.
• A pedestal sink is supported by a single freestanding leg.
• A flushometer valve is used to flush toilets without a tank.
• The primary purpose of a P-trap is to prevent sewer gases from entering a building.
• A freestanding bathtub is installed above the floor and not built into a wall.
• A triple-basin sink is designed for commercial kitchens with three compartments.
• Drinking fountains must be installed in public areas with sanitary drainage.

General Plumbing Principles & Regulations

• Plumbing materials must be durable and approved.
• Vent terminals must extend above the roofline.
• A backflow preventer stops the reverse flow of contaminated water.
• The minimum slope for a drainage pipe is 1%.
• A plumbing system must be tested for leaks using water, air pressure, and smoke.
• The minimum size of a building drain is 100 mm.
• Plumbing fixtures must be made of non-absorbent material.
• A plumbing trap must always contain a water seal.
• A grease interceptor is required in restaurants and commercial kitchens.
• The main cause of sewer gas entering a building is missing or dry traps.

Drainage and Waste Systems

• A waste pipe conveys wastewater from fixtures to the building drain.
• A stack is the vertical pipe that carries sewage or wastewater downward .
• A sanitary drainage system carries waste efficiently while preventing sewer gases from entering the building.
• The building drain is the main pipe in a building drainage system that receives discharge.
• A cleanout allows inspection and cleaning of the pipe in a drainage system.
• A trap seal prevents odors and sewer gases from entering the building in a plumbing trap.
• The minimum size for a main building drain in a typical residential home is 100 mm.
• "Gray water" is relatively clean wastewater from sinks, showers, and laundry.
• A plumbing vent provides fresh air, allows gases to escape, and equalizes pressure in the drainage system.
• A combined sewer carries both wastewater and stormwater.

Water Distribution Systems

• A service pipe connects the building to the water main.
• The distribution pipe is the main water supply line inside a building.
• Lead is not recommended for potable water supply.
• A water meter measures water usage.
• A pressure-reducing valve lowers excessive pressure.
• The standard pressure range for a residential water supply system is 30-50 psi.
• Water supply pipes must be installed above sewer pipes.
• A ball valve controls flow at a water meter.

Plumbing Safety and Codes

• An air gap prevents backflow in a plumbing system.
• Buildings with multiple floors need pressurized systems with booster pumps.
• The depth for burying water supply pipes to prevent freezing depends on local climate and frost depth.
• Plumbing codes standardize design/installation, ensure safety, and prevent potable water contamination.
• A cross-connection is a potable water supply connected to a potential contaminant source.
• The National Plumbing Code of the Philippines (NPCP) ensures proper plumbing installations and safety.
• The minimum clearance from the center of a toilet to the nearest wall should be 375 mm.
• Grease traps in commercial kitchens prevent grease and solid waste from clogging drainage systems.
• A plumbing system should be tested before and after covering the pipes for leaks.
• The maximum allowable lead content in drinking water pipes and fittings is 0%.
• The standard kitchen sink drain outlet height from the floor is 450 mm.
• Plumbing inspections are conducted before concealment, after installation, and during operation.

Special Plumbing Systems

• High-rise buildings use booster pump systems to maintain water pressure.
• Black steel piping is used in fire protection systems.
• A vacuum drainage system removes wastewater through a vacuum rather than gravity.
• A graywater system recycles wastewater for non-potable use.
• PVC is not suitable for use in a gas piping system.
• A sump pump removes accumulated water from basements.
• The recommended slope for horizontal drain pipes is 2%.
• A manhole in a sewer system provides access for maintenance and cleaning.
• The maximum allowable bend in a vent pipe is 45°.
• A plumbing vent must terminate at least 300 mm above the roof.