Quiz 2

ASHRAE has defined "acceptable" indoor air quality as: a) "air in which there are no harmful concentrations of known contaminants and with which 80% of people exposed do not express dissatisfaction" b) "air which is regularly circulated and flushed during unoccupied hours" c) "air that is maintained at a relatively constant temperature of 72o F" d) "air that maintains comfortable conditions when the majority of building occupants are wearing clothing with a value of 1 CLO"

a) "air in which there are no harmful concentrations of known contaminants and with which 80% of people exposed do not express dissatisfaction"

Using Figure D.2(c), the solar azimuth for Tulsa, OK (36°N) at 10 am (solar time) on December 21 is: a) 30° east of south b) 30° west of south c) due south d) 60° east of south

a) 30° east of south

Which intersection of relative humidity and air temperature is outside the ASHRAE thermal comfort zone? a) 60% and 86oF (30oC) b) 60% and 68oF (20oC) c) 40% and 77oF (25oC) d) 50% and 75oF (24oC)

a) 60% and 86oF (30oC)

Which of the following is a true statement about a breathable wall? a) The wall system is dependent upon a building being under negative pressure, such that airflow is being forced out. b) The wall must have holes at each floor. c) The wall must have fan units at each floor. d) At least 4 inches (100 mm) of clearance must be provided for the wall's expansion and contraction.

a) The wall system is dependent upon a building being under negative pressure, such that airflow is being forced out.

The heat transfer process of conduction is primarily dependent upon: a) a difference in surface temperatures b) the number of CLOs per person c) a change in air temperature d) radiation

a) a difference in surface temperatures

The following information cannot be found on manufacturer-provided Material Safety Data Sheets (MSDS): a) a prediction of pollution emission rates b) the material's chemical constituents c) handling procedures d) physical data such as melting point, flash point, etc.

a) a prediction of pollution emission rates

The vertical shadow angle for 100% shading would extend from: a) a window sill to the outer edge of an overhang b) a window sill to the inner edge of an overhang c) from the overhang to the floor inside the building envelope d) from the outer edge of the horizontal overhang to the outer edge of the vertical overhang

a) a window sill to the outer edge of an overhang

A properly sized horizontal overhang can provide 100% shading only when: a) the solar-window azimuth is 0o b) the window is facing north c) the window is facing west d) it is longer than the hypotenuse of the profile angle

a) the solar-window azimuth is 0o

Mean radiant temperature can be defined as: a) the uniform temperature of a surrounding enclosure in which radiant transfer from the human body would equal the actual radiant heat transfer within a building space b) the average apparent temperature experienced by all individuals in a room c) the difference between the heat contained in a building's thermal mass and that retained by its occupants d) the average temperature experienced by a building's exterior cladding

a) the uniform temperature of a surrounding enclosure in which radiant transfer from the human body would equal the actual radiant heat transfer within a building space

About how much "new" air would an indoor space have after one hour of ventilation at the rate of one air change per hour (ACH)? a) 100% b) 63% c) 50% d) 10%

b) 63%

Using Figure D.2(c), the solar altitude for Jackson, MS (32°N) at solar noon on June 21 is: a) 11° b) 82° c) 45° d) 56°

b) 82°

Which compound can be used as a "canary in the coal mine" to warn of the buildup of other pollutants? a) NO2 b) CO2 c) H2O d) NaC

b) CO2

The sun's position on May 21 would be the same as on: a) June 21 b) July 21 c) January 21 d) December 21

b) July 21

The baseline of a shading mask corresponds to which aspect of a building? a) a window sill b) a building wall c) the horizontal edge of the shading device d) the vertical edge of the shading device

b) a building wall

The Passive House concept is best described as: a) an energy standard b) an energy standard and set of design and construction principles c) a set of design principles d) a set of construction principles

b) an energy standard and set of design and construction principles

Movable shading devices have not been implemented as widely as possible because: a) they cannot provide shade for windows facing south b) building managers perceive them as expensive to maintain and prone to breakdowns c) occupants tend to operate them improperly d) surveys have indicated that occupants prefer not to have moving elements attached to building exteriors

b) building managers perceive them as expensive to maintain and prone to breakdowns

As air temperatures approach those of our own body, the following mechanism for heat flow becomes essential: a) radiation b) evaporation c) convection d) conduction

b) evaporation

Humphreys and Nicol's equation for indoor comfort differs from other comfort models in that: a) it is more accurate b) it does not take relative humidity into account c) it does not take averages of indoor or outdoor temperature d) it only applies to buildings in arid climates

b) it does not take relative humidity into account

The most common energy source for regenerating desiccant cooling devices today is: a) solar radiation b) natural gas c) gasoline d) electricity

b) natural gas

Which projection method is best described as "a two-dimensional graph of the sun's position in Cartesian coordinates, with the azimuth plotted on the horizontal axis and altitude on the vertical axis?" a) stereographic projection b) rectilinear projection c) equidistant projection d) gnomonic projection

b) rectilinear projection

The ASHRAE thermal comfort zones, as plotted on a psychrometric chart, are primarily defined by: a) the extent of convection in a given space b) relative humidity and operative temperature c) the federal government d) ambient air pressure and temperature

b) relative humidity and operative temperature

For the best diffusion of incoming air throughout a building, an air-to-air heat exchanger should operate under which condition? a) only when exterior temperature is below freezing b) with the exchanger located at a central forced-air fan c) when exterior temperature is equal to indoor temperature d) when exterior temperature is greater than indoor temperature

b) with the exchanger located at a central forced-air fan

A ____ relative humidity change will affect a person's comfort about as much as a 2Fo (1Co) change in temperature. a) 10% b) 20% c) 30% d) 50%

c) 30%

The exhaust capacity of a principal residential building exhaust fan should be at least ___ of the total HVAC system airflow capacity. a) 10% b) 20% c) 50% d) 60%

c) 50%

A generally accepted air exchange rate for air cleaning equipment is: a) 3-4 air changes per hour b) 4-6 air changes per hour c) 6-10 air changes per hour d) 10-20 air changes per hour

c) 6-10 air changes per hour

One would expect the sun to describe a similar path through the sky in which pair of cities: a) Seattle and Miami b) Los Angeles and Chicago c) Portland, Oregon and Boston d) San Francisco and Houston

c) Portland, Oregon and Boston

The insulating value of clothing is measured in CLO units, which is equivalent to: a) normal female business attire in 2005 b) the typical clothing worn by high school students in 1995 c) a typical American man's business suit in 1941 d) typical college student attire in 1965

c) a typical American man's business suit in 1941

When considering the following methods of providing acceptable IAQ, a designer must first and foremost: a) isolate unavoidable sources of pollution b) provide an adequate supply of fresh air c) choose materials and equipment carefully d) maintain the building and equipment in clean condition

c) choose materials and equipment carefully

The following sunpath projection chart is used for building shadow studies: a) equidistant b) rectilinear c) gnomonic d) stereographic

c) gnomonic

At 100% relative humidity: a) wet-bulb temperature is greater than dry-bulb temperature b) wet-bulb temperature is less than dry-bulb temperature c) wet-bulb temperature is equal to dry-bulb temperature d) the relationship of wet-bulb to dry-bulb temperature can only be determined using a psychrometric chart

c) wet-bulb temperature is equal to dry-bulb temperature

. Anywhere on the Earth's surface, what is the greatest deviation between true and magnetic north? a) 10o b) 20o c) 90o d) 50o

d) 50o

Which filter type is considered least effective in cleaning air? a) a media filter b) an air washer c) an adsorption filter d) a panel filter

d) a panel filter

A horizontal overhang in the Northern Hemisphere would provide the best sunshading protection for what type of condition? a) an east-facing window in the winter b) a west-facing window in the summer c) a north-facing window in the winter d) a south-facing window in the summer

d) a south-facing window in the summer

Passive House comfort criteria set a maximum limit on: a) relative humidity level b) air temperature c) mean radiant temperature d) air velocity

d) air velocity

In the United States, the vertical shadow angle is sometimes also called: a) the sunpath angle b) the spectral analytical angle c) the raytrace angle d) the profile angle

d) the profile angle

What is the recommended low humidity limit for the ASHRAE thermal comfortzone? a) 10% b) 5% c) 2% d) there is no recommended low humidity limit

d) there is no recommended low humidity limit

List the three categories of factors that affect comfort:

personal, measurable environmental, and psychological