Building Services: Water Supply, Sanitary Appliances, Drainage, and Fire Control

Comprehensive practice flashcards covering water supply systems, sanitary appliances, drainage design, sewage disposal, and fire safety systems based on the lecture by Dr. Desmond Opoku.

What are the two primary categories of water sources identified in the lecture?

Surface sources (lakes, rivers, streams, ponds, roof run-off, sea) and underground sources (boreholes, wells, springs, waterfalls).

According to the transcript, what is the definition of 'Head' in relation to water pressure?

It is the height to which water in the main would rise in a vertical pipe ($10\,feet$ of depth equals $10\,feet$ of head).

What is the recommended minimum and maximum 'Head' for water mains?

The minimum head is $30\,m$ and the recommended maximum head is $70\,m$.

List the three systems of water distribution in houses.

Direct System, Indirect System, and Combined System.

What are the eight properties of potable water specified in the notes?

1. Clear/free from suspended matter, 2. Colourless, 3. Free from harmful bacteria, 4. Pleasant to taste, 5. Free from harmful chemicals, 6. Moderately hard, 7. Odourless, 8. Neutral PH ($7$).

What is the specific range for residual chlorine required during water sterilization?

Between $0.1$ and $0.3\,ppm$.

Differentiate between Temporary and Permanent hardness of water.

Temporary hardness is caused by calcium bicarbonate and can be removed by boiling; Permanent hardness is caused by calcium/magnesium sulphates or chlorides and cannot be removed by boiling.

What are the three main types of water pumps?

Centrifugal pump, Displacement pump, and Rotary pump.

What is the difference between 'Foul' and 'Waste' sanitary appliances?

Foul (soil) appliances use water for flushing or disposing of foul matter; Waste appliances use water for drinking, cleaning, or culinary purposes.

What are the two classified types of Water Closet (WC) pans?

Wash Down and Siphonic (which includes Double Trap and Single Trap).

What purpose does a 'Trap' and its 'Seal' serve in sanitary appliances?

The trap contains a column of water (the seal) that prevents odors from rising from the sanitary pipe-work into the building.

What is the standard vertical height for a water seal in waste appliances like basins and baths?

$75\,mm$.

What is the formula for Reynolds number ($R$) and what value indicates turbulent flow?

$R = \frac{\rho vd}{\mu}$; a value greater than $2000$ indicates turbulent flow, while less than $2000$ indicates streamline/laminar flow.

State the D’Arcy formula for calculating head loss ($h$) due to friction.

$h = \frac{4fLv^2}{2gd}$.

What is a 'Demand Unit' (DU) based on for domestic pipe sizing?

A domestic basin cold water flow rate of $0.15\,l/s$, a tap discharge duration of $30\,seconds$, and a time interval between usage of $300\,seconds$.

According to the Building Regulations, what is the minimum capacity for a cesspool below the inlet level?

$18,000\,litres$.

What is the formula for determining the capacity ($C$) of a septic tank based on the number of persons ($P$) served?

$C = (180 \times P) + 2000$.

What are the three essential elements required for a fire to exist?

Fuel, Heat, and Oxygen.

Identify the five classes of fire (A through E).

Class A: Solid fuels; Class B: Inflammable liquids; Class C: Inflammable gases; Class D: Inflammable metals; Class E: Electrical current.

What does the 'PASS' acronym stand for in the context of using a fire extinguisher?

P - Pull the pin; A - Aim the nozzle; S - Squeeze the handle; S - Swing the extinguisher from side to side.

What color code identifies a Carbon Dioxide ($CO_2$) fire extinguisher?

Red with a black band.

How does a 'Drencher' system differ from a 'Sprinkler' system?

A sprinkler sprays water over an internal area when a heat bulb breaks; a drencher discharges water over roofs, walls, windows, and doors to protect the external faces of a building from adjacent fire risks.