Page 337 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED Indoor Envir onmental Quality 299

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measurement and is 10 m. If you assume that these particles are round and have a specific gravity
of 2, what are their volume ranges and mass ranges?
5. IEQ credit 4.3 limits total VOC emissions and also several specific compounds emissions, including
formaldehyde from carpets and carpet cushioning. It also limits the VOC level (concentration) in the
carpet adhesive as per IEQc4.1. You are carpeting a room that is 4.5 m by 6 m wide and 3.2 m tall, and
it is totally sealed so that there are no air exchanges. If you install carpet cushioning and carpet on
the floor that all are at the emissions limits as established by the Carpet and Rug Institute (CRI) for
formaldehyde and as listed in Table 6.4.3., how long (in hours) will it take until the concentration in
the room of formaldehyde reaches the threshold for human irritation (around 0.1 ppm)? Remember,
we are assuming a perfectly sealed room. You can assume that both the formaldehyde and the air
are ideal gases.
6. You are carpeting a room that is 4.5 m by 6 m wide and 3.2 m tall, and the room changes out
its full volume of air every 4 h. If you install carpet cushioning and carpet on the floor that all are
at the emissions limits as established by the Carpet and Rug Institute (CRI) for formaldehyde as
listed in Table 6.4.3, what is the steady-state concentration of formaldehyde in the room? Please
note the following:
• Steady state means that the mass rate of formaldehyde leaving the room in the air which is
leaving equals the mass rate of the formaldehyde which is being emitted into the room from
the carpet system as noted. (See Chap. 10 for mass balance box models.)
• You can assume that both the formaldehyde and the air are ideal gases.
7. You are carpeting a room that is 4.5 m by 4.5 m wide and 3.0 m tall, and the room changes
out its full volume of air every 2 h. If you install carpet cushioning and carpet on the floor that
all are at the emissions limits as established by the Carpet and Rug Institute for formaldehyde as
listed in Table 6.4.3, what is the steady-state concentration of formaldehyde in the room? Please
note the following:
• Steady state means that the mass rate of formaldehyde leaving the room in the air which
is leaving equals the mass rate of the formaldehyde which is being emitted into the room
from the carpet system as noted. (See Chap. 10 for mass balance box models.)
• You can assume that both the formaldehyde and the air are ideal gases.
8. Your room has equal mass concentrations of particulate matter in the 1- to 3-μm range and
in the 3- to 10-μm range and an insignificant amount of the smaller particulate matter on a mass
basis. What is the overall efficiency of a MERV 8 filter and a MERV 13 filter for this room based
on Table 6.3.1?
9. Your room has approximately 25 percent on a mass basis of the particulate matter in the 1- to
3-μm range, approximately 20 percent in the 3- to 10-μm range, and the remainder in the 0.3- to
1.0-μm range. What is the overall efficiency of a MERV 8 filter for this room based on Table 6.3.1?
What is the overall efficiency of a MERV 13 filter for this room based on Table 6.3.1?
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10. Ambient air PM2.5 1997 maximum standards are 15 μg/m on an average annual basis and
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65 μg/m on an average 24-h basis in 1997. The 24-h standard was tightened to 35 μg/m in 2006.
You have a room that is 4 m by 4 m by 3 m. If you flush out the volume of this room and it is at
the maximum annual ambient air standard for PM2.5, what mass of PM2.5 would you expect to
collect on a MERV 13 filter?
11. Estimate the time it would take to flush out a building after occupancy for the minimum
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rates set in LEED 2009 IEQ credit 3.2 Option 1, Path 1. The standard gives a total of 14,000 ft of
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outside air per square foot. The Path 2 alternate flush-out option allows for occupancy after 3500 ft is
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complete. At the minimum rate of 0.30 ft /(min · ft ) for a typical 9-h day occupancy (8 h plus lunch),