1. Why take the longest run when sizing a fan?
2. Why should pressure drop be 0.4-0.6 Pa in sizing ducts?
HVAC
AIR HANDLING UINIT is mostly used to condition big spaces, air is conditioned outside and ducted
inside the building. Diffusers are used to distribute the air inside the building. Hideaway unit work in
a similar manner. Except they are not outside.
Negative pressure – more air leaving (extracting) than one flowing inside (supply). So air pressure is
more outside than inside, in this case air will from outside to the inside….ideal for kitchens and
toilets since the smell should be kept inside.
Positive pressure – more air flowing inside the building than one leaving (extraction). Ideal since it
keeps dust away since air will flow from high pressure to low pressure, hence dust will not enter the
space.
FIRE PROTECTION
Fire hydrants and hose reels are both crucial tools in firefighting, but they are typically not used
simultaneously due to the way water supply and pressure are managed in a fire protection system12.
1. Water Supply and Pressure: Fire hydrants and hose reels are connected to the same water
supply. Using them simultaneously could lead to a drop in water pressure, which could affect
the effectiveness of firefighting efforts1. Adequate water pressure is crucial for the proper
functioning of both fire hydrants and hose reels1.
Size hose reel pumps, assuming a maximum of two hose reels will be operational. Hose reel covers a
maximum of 30m around it, if more than two hose reels are to be used then a fire hydrant should be
used.
MEDICAL GAS SUPPLY PIPELINE
The following general information is required to
design an MGPS:
a. schedule of provision of terminal units;
b. design flow rates and pressure requirements at each terminal unit;
c. diversified flows for each section of the pipeline system;
d. total flow.
DRAINAGE
GULLY TRAP;-
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used for grey water (shower, sink, WHB)
serves as an access point in case of blockage
traps bad smell