The divergence of the airstream in a horizontal or vertical plane after it leaves the outlet.
What is Spread?
What is the average spread of a mass of air entering a space?
100
Cataloged sound data assumes this many diameters of straight duct.
What is 10 Diameters?
Why do we assume this distance of straight duct?
100
The percentage distance throw decreases when air travels across into a free space rather than across a surface.
What is 30 percent?
Why?
100
The velocity at which the air must be travelling inside the occupied zone (6 feet standing or 3.5 feet for sitting occupant).
What is 50 feet per minute (FPM)?
Why is this velocity important?
100
A return slot should be located here to carry away solar heat gain.
What is Above a Window.
Why is this a good idea?
200
A method which can be used to verify occupant comfort in cooling mode.
What is ADPI 80. What does ADPI 80 mean?
200
Sound performance tests for diffusers are conducted in accordance with this Standard.
What is ASHRAE Standard 70?
200
This Standard mandates a 5-deg F vertical temperature stratification in the Occupied Zone.
What is ASHRAE Standard 55?
200
This is the best way to present a sound requirement on a specification or a schedule.
What is octave band sound power.
Why octave band and not NC?
200
Which diffusers carry a higher overall system cost (labor, install, etc), perforated diffusers or plaque diffusers?
What are perforated diffusers.
Why might this be?
300
The difference between a grille and a register.
What is the presence of a face-adjustable volume damper (with a finger tab).
300
This standard is used to estimate room sound power from known sound pressure.
What is AHRI Standard 885.
300
Which diffuser performs better in a VAV system, a perforated diffuser or a plaque diffuser?
What is a plaque diffuser.
Why?
300
The 10 dB reduction allowed by Standard 885 during grille testing.
What is room absorption.
300
This is the location and height where a t-stat should not be located. There are multiple possible answers.
What is close to the floor, on exterior walls, in direct sunlight, close to supply grilles.
Why?
400
The mass of air which enters a room through free round openings, grilles, perforated panels, ceiling diffusers and other outlets is called?
What is a Primary Air Jet.
400
These are the frequencies (in Hz) where GRDs typically peak in terms of noise transmission.
What are 500, 1000, 2000 Hz.
Why?
400
Air is thrown horizontally across a ceiling, and the throw decreases as the air travels. Is it winter or summer time?
What is summer time.
Why?
400
The two requirements of ASHRAE 55 when heating from the ceiling.
What are 15 degree dT and a 150 FPM velocity that reaches 4.5' above the floor.
400
These two types of Air Distribution devices are beneficial in Hi-Bay designs (over 12') due to the need to heat/cool the occupied area only.
What is Displacement Ventilation and Underfloor Air Distribution (UFAD)?
Why are these two good ideas for high-ceiling applications?
500
The primary jet which enters a space while traveling along a ceiling or wall.
What is an entrained jet of air.
What is the opposite of an entrained jet?
500
This is how NC is typically calculated from octave band data.
What is by overlaying octave band sound power data on an octave band vs. NC curve chart.
500
This is the ideal Delta-t for a displacement (DV) or underfloor air distribution (UFAD) application.
What is 65 degrees.
Why?
500
The Required amount of Ventilation air that must be added (per ASHRAE 62.1) if you do not meet the 15 deg. delta T and the 150 fpm rules and the 5 deg. temperature stratification (from Standard 55).
What is 25 %?
Why might this be?
500
This device utilizes chilled/heated water, primary air supply and induced room air to treat the space. (not a Terminal Unit)
What are Chilled Beams.
What is the typical induction ratio for overhead CB's?
What are some design concerns associated with CB's?