Title: ASHRAE Standard 62'12004
1(No Transcript)
2 The Use of Gas Phase Filtration and ASHRAE
Standard 62.1
Brian Monk , P.E. Carrier Corporation ASHRAE DL
3 Overview
- IAQ and ASHRAE Std 62.1-2007
- Key requirements
- Indoor source control
- Outdoor source control
- Ventilation rates
- Case Studies
4Indoor Air Quality
- People spend a lot of time indoors (90 )
- Poor IAQ reduces comfort
- Poor IAQ reduces well-being
- Irritation (Sick Bldg Syndrome)
- Health (Bldg Related Illness)
5Indoor Air Quality Design Strategies
- Comply with Local building code
- Comply with the specifications
- Comply with ASHRAE Std. 62.1
- Adopted entirely by local codes
- Adopted partially by local authorities
6ASHRAE Standard 62.1-2007
- Purpose
- to specify minimum ventilation rates and indoor
air quality that will be acceptable to human
occupants - Scope
- all indoor...spaces that people may occupy
- considers chemical, physical and biological
contaminants
7ASHRAE Standard 62.1-2007
- A mixed-language standard,an evolutionary
process - Std 62-1973 - first issued
- Std 62-1981 - lower rates
- Std 62-1989 - higher rates
- Std 62-1999 - O.A. Quality
- Std 62-2001 - refinement
- Standard 62.1-2004 Mandatory Language
8ASHRAE Standard 62.1-2004
- Std 62.1 for commercial andinstitutional spaces
- Minimum requirements
- Code-intended mandatory language
- User Manual for Std 62.1
- Guideline 62.1 (informational)
- State-of-the-Art design guidance
- Std 62.2 for residential spaces
9ASHRAE Standard 62.1-2007
- Std 62.1 for commercial andinstitutional spaces
- Applies to high-rise residential(three stories
or more) - Std 62.2 for residential spaces
- Applies to single family \
- Applies to multiple-family less than three
stories
10ASHRAE Standard 62.1-2007 Dilution of
Contaminants
- The ventilation standard cant simply specify
minimum outdoor airflow - Because minimum outdoor airflow required depends
upon - Indoor contaminant source strength
- Target indoor contaminant levels
- Outdoor contaminant concentration
11 ASHRAE Standard 62.1-2004 Dilution of
Contaminants
Ci Co G/Vo
Indoor Target Concentration
Net Indoor Generation Rate
Emission - Removal
Vo G/(Ci - Co)
Outdoor Concentration
Outdoor Airflow
12Indoor Pollutants
- IAQ and ASHRAE Std 62.1-2004
- Key requirements
- Indoor source control (G)
- Outdoor source control (Co)
- Ventilation rates (Vo)
13(No Transcript)
14(No Transcript)
15Air Contaminant Sizes
SCAN. ELEC. MICROSCOPE
OPT. MICROSCOPE
EYE
SMOG
FUMES
DUSTS
SPORES
TOBACCO SMOKE
BACTERIA
HUMAN HAIR
VIRUSES
MOLECULES
POLLEN
16(No Transcript)
17(No Transcript)
18Indoor Source Control
- Strong sources (can over-tax ventilation system
with contaminants) - Particulate matter (can degrade equipment
operation) - Microbial growth (can cause odors, allergies and
maybe illness) - ETS (can cause odors, illness and cancer)
G
Vo G/(Ci - Co)
19(No Transcript)
20Filtration
- For cleanliness, must filter at MERV 6 or higher
for PM10.
Std 62-2007 5.9 Particulate Matter Removal.
Particulate matter filters or air cleaners having
a minimum efficiency reporting value (MERV) of
not less than 6shall be provided.
G
21(No Transcript)
22microbial growthBasics Of The Problem
- Microbial growth bacteria and fungi (mold,
mildew) growing indoors - May be the major cause of IAQ-related complaints
today - Can produce odors, allergens, toxins
- Can cause building damage, discomfort, allergic
reactions (asthma) possibly illness
G
23microbial growthSolution Depends On Location
- On the walls (i.e., in the space)
- Fix pipe leaks, dry carpet after shampooing,
control relative humidity and building pressure - In the walls
- Fix wall/roof leaks, minimize vapor pressure
diffusion, control relative humidity and building
pressure - In the air handler and ducts
- Manage condensate, allow access for cleaning
G
24Control Relative Humidity
- This will help
- Currently 65 RH limit required
Std 62-2004 5.10 Relative humidity in
habitable spaces preferably should be maintained
between 30 and 60 relative humidity to minimize
growth of allergenic or pathogenic organisms.
G
25Control Building Pressurization
- Limits transfer air cross contamination
- Often required by local code (Hospitals)
- In future expect positive building pressure
requirement in predominantly cooling climates
G
26Not Completely Addressed
- Relative humidity control and positive building
pressure help walls dry-in in humid climates,
but doesnt solve problem - Envelope issues not really within scope of
ventilation standard - No requirement related to envelope leaks (biggest
source of moisture in walls, roof) - No requirement for vapor retarder (a big problem
in humid climates)
G
27Manage Condensate
- Standing water allows microbial growth (mainly
bacterial) - Persistently wet surfaces due to spitting and
carryover encourage microbial growth - Accumulated dirt can absorb moisture and
encourage microbial growth (fungi)
G
28(No Transcript)
29Manage Condensate
- To avoid standing water, drain pans must drain
(AHU)
Std 62-2004 5.11.1 Drain Pan Slope. Pans
intended to collect and drain liquid water shall
be sloped at least 1/8 in. per foottoward the
drain outlet or shall be otherwise designed to
ensure that water drains freely from the pan
... 5.11.2 Drain Outlet. The drain pan outlet
shall be located at the lowest pointand shall be
of sufficient diameter to preclude drain pan
overflow
G
30(No Transcript)
31Manage Condensate
G
- To avoid spitting in draw-thru units, drain
lines must seal
Std 62-2004 5.11.3 Drain Pan Seal. the drain
line shall include a P-trap or other sealing
device designed to maintain a seal against
ingestion of ambient airwhether the fan is on or
off.
32Manage Nutrient Sources
G
- Accumulated dirt can absorb moisture and
encourage microbial growth (mainly fungi) - Some airstream surface materials can be colonized
by microbial growth (fungi)
33 Manage Nutrient Sources
- To manage accumulation of dirt, air handler
surfaces must be accessible for cleaning
G
Std 62-2004 5.12.2 Finned-Tube Coil Selection
for Cleaning. Individual finned-tube coilsshall
be selected to result in no more than0.75
in.wcpressure drop when dry coil face velocity
is500 fpm. 5.14.2 Ventilation Equipment Access.
Access doors, panels, or other means shall be
provided ...to allow convenient and unobstructed
access sufficient to inspect, maintain, and
calibrate all ventilation system components...
34Environmental Tabacco Smoke
G
- ETS is a Class A carcinogen with no established
acceptable concentration - So, minimum ventilation rates in table no longer
accommodate a moderate amount of smoking - In many buildings, smoking is allowed in some or
all areas, so system designer needs - Separation guidance
- Ventilation-for-odors guidance
35Separation
G
- When a building includes smoking-permitted (ETS)
areas, they must be separated to minimize ETS
concentration in ETS-free areas - Currently no requirements
- In the future expect specific separation
requirements in Addendum 62g.
36Separation
- For example, 62g may require
- Pressurization of ETS-free area
- Separation of ETS-free from ETS area using walls
with doors or unidirectional airflow - No recirculation or transfer air from ETS to
ETS-free area - Exhaust air from ETS area to outdoors
- Posted sign This Area May Contain ETS
G
37 Ventilation for Odors
- To achieve perceived acceptable indoor air
quality, must ventilate ETS areas - Currently specific ventilation requirements for
smoking lounges (see Table 2) - In the future, per Addendum 62o, expect
- No spaces that permit smoking listed in Table 2
- Ventilation recommendations in an Appendix.
G
38Outdoor Air
- IAQ and ASHRAE Std 62
- Key requirements
- Indoor source control (G)
- Outdoor source control (Co)
- Ventilation rates (Vo)
39Outdoor Source Control
- Ambient air quality (can impact indoor air
quality) - Filtration and/or air cleaning (can reduce impact
of poor ambient air quality) - Intake separation (can reduce introduction of
contaminants from local strong sources)
Co
Vo G/(Ci - Co)
40outdoor source controlAmbient Air Quality
- If regional outdoor air quality is poor it can
result in poor indoor air quality - If local outdoor air is contaminated, it can
result in poor indoor air quality
Co
41outdoor source controlAmbient Air Quality
- Regional outdoor air quality must be evaluated
ASHRAE Std 62-2004 4.1 Regional Air Quality.
The status of compliance with national ambient
air quality standards shall be determined for the
geographic area of the building site. In the
United States, compliance status shall be either
in attainment or non-attainment with
...NAAQS
Co
42National Primary Ambient- Air Quality Standard
(for O.A. as set by the US EPA)
43outdoor source controlAmbient Air Quality
- Local outdoor air quality must be evaluated
ASHRAE Std.62-2004 4.2 Local Air Quality. An
observational survey of the building site and its
immediate surroundings shall be conductedto
identify local contaminants from surrounding
facilities that may be of concern...
Co
44outdoor source controlFiltration/Air Cleaning
- If outdoor air is non-attainment for PM10 or
ozone (very high levels), clean it
ASHRAE Std.62-2004 6.2.1.1 Particulate Matter.
particle filters ...shall be provided with
efficiency MERV 6 or higher ASHRAE
Std.62-2004 6.2.1.2 Ozone. Air-cleaning devices
for zone shall be providedwith a minimum
volumetric ozone removal efficiency of 40
Co
45(No Transcript)
46Absorbtive Media
- POTASSIUM IMPREGNATED ALUMINA
- COAL BASED ACTIVATED CARBON
- ACTIVATED CARBON IMPREGNATED WITH PHOSPHORIC
-
- ACTIVATED CARBON IMPREGNATED WITH POTASSIUM
HYDROXIDE
47Removal Mechanisms
- ADSORPTION
- ABSORPTION
- CHEMISORPTION
- CATALYSIS
48Pore Structure
- Macropores (r gt 25 nm)
- Used to enter
- Mesopores (r 1-25 nm)
- Used to transport
- Micropores (r lt 1 nm)
- Used to adsorb
49Adsorption IsothermActivated Carbon vs General
HC
100.00
10.00
1.00
Cubic feet of MM-300 at 1000 CFM
0.10
0.01
0.00
1
10
100
1000
Operation Time, days
50Capacity vs Retentivity
- CAPACITY
- Mass of contaminant adsorbed when the
concentration of the contaminant at the inlet is
equal to the outlet concentration.
- RETENTIVITY
- When the maximum capacity of the media is
reached, the inlet air is substituted with fresh
air. The mass of the contaminant remaining in
the media when the outlet concentration is
non-detectable.
51Properties of Sorbent Materials
52Impregnated Activated Carbon
- Impregnation enhances the inherent properties of
an activated substrate by finely distributing
specific chemicals to target specific
contaminants. This process alters the removal
mechanism from physical adsorption to
chemisorption.
53Chemisorption
- Oxidation Reaction
- Oxidant Contaminant Oxygen Carbon
Dioxide Water -
- Acid-Base Reaction
- Acid Base Salt Water
54Adsorption Wave
T1
T2
T3
Unused Media
Unused Media
Unused Media
Active Media
MTZ
Active Media
MTZ
Active Media
MTZ
Spent Media
Spent Media
Spent Media
55Laboratory Analysis
- Optimize Media Change-Out
- Verify Media Performance
- Respond to Changing Contaminant Loads
56Residence Time, TRS
- The superficial amount of time that an air-stream
is in contact with the chemical media. - Ft3 of Media
- CFM
x 60
TRS
57UNIVERSAL SIDE ACCESS HOUSING THIN BED
RECIRCULATION SYSTEM
- FEATURES
- High Sealing Integrity
- Size Flexibility
- Multiple Stages of Particulate and Gas-Phase
Filtration - Optional Bi-Polar Ionization Section
58(No Transcript)
59outdoor source controlIntake Separation
- Should separate intakes from strong outdoor
sources - Currently, no requirements
- In the future, minimum separation distance from
intake for specific outdoor sources - Dumpster -- 15 ft
- Cooling tower exhaust -- 25 ft
- Loading dock -- 25 ft
Co
60Outdoor Air Treatment
61(No Transcript)
62Ventilation Rates
- IAQ and ASHRAE Std 62
- Key requirements
- Indoor source control (G)
- Outdoor source control (Co)
- Ventilation rates (Vo)
63Ventilation Rates
- First, why introduce outdoor air?
- To dilute and remove indoor contaminants
- To replace indoor air removed by exhaust
- Second, how much outdoor air is needed?
- For design, use IAQ Procedure, or
- For design, use Ventilation Rate Procedure
Vo
Vo G/(Ci - Co)
64Indoor Air Quality Procedure
- Performance-based requirements
- Given Ci target, Co and G values, and find Vo
- Lists limits for 10 contaminants, but open-ended
list - Requires a subjective analysis for odors
- Describes the use of air cleaning to reduce OA
rates - Not widely used its too costly and too risky
Vo
65Ventilation Rate Procedure
- Prescriptive ventilation requirements
- Without quantifying Co or G, assumes Ci is OK if
prescribed outdoor airflow is provided - Prescribes space (breathing zone) ventilation
rates in Table 2 - Most widely used procedure
Vo
66Ventilation Rate Procedure
- 1. Look up breathing zone ventilation rate in
Table 2 - Rp cfm/person (most spaces)
- Ra cfm/sf (some spaces)
6 ft
Vo
Breathing zone Rp or Ra
67Space Ventilation Rates
- Table 6-1 Minimum Ventilation Rates
62.1Rp cfm/p 5 10 7.5 7.5 5
62.1 Ra cfm/sf 0.06 0.6 0.06 0.12 0.06
- Space Type
- Office _at_ 5p/1000 sf
- K2 Classroom _at_ 25p/1000 sf
- Lecture Classroom _at_ 65p/1000 sf
- Retail Sales _at_ 15p/1000 sf
- Auditorium _at_ 150p/1000 sf
Vo
68Ventilation Rate Procedure
- 2. Calculate breathing zone (space) ventilation
airflow - Vbz Rp Pd or Vbz Ra A
- 3. Calculate zone ventilation airflow
- Vo Vbz / Eac
- Where Eac room air change effectiveness
Vo Vbz / Eac
Vo
Vbz RpP
Breathing zone
69Ventilation Rate Procedure
- 4. Calculate system intake airflow, Vot
- Vot Y Vst
- Y corrected intake fraction X / (1 X - Z)
- Vst total primary airflow S Vs (zone primary)
- X average ventilation fraction S Vo / Vst
- Z critical zone ventilation fraction Voc /
Vsc - Y depends on system type
- Single space
- Dedicated outdoor air
- Multiple-space recirculating
Vo
70Intermittent Occupancy
- Allows ventilation design for average occupancy
rather than peak occupancy - Widely used for conference rooms, classrooms and
churches to reduce equipment cost
Std 62-2004 6.2.6.1 Intermittent or Variable
Occupancy. Where peak occupancies of less than
three hours duration occur, the outdoor airflow
rate may be determined based on the basis of
average occupancy ... provided the average
occupancy used is not less than one-half the
maximum
71Outdoor Air Intake
- Must maintain minimum outdoor air intake flow
(Vot) at all loads - Therefore, VAV systems usually need modulating
(not fixed position) OA dampers
ASHRAE Std.62-2004 5.4 Ventilation System
Controls. The system shall be designed to
maintain the minimum outdoor airflow as required
by Section 6 under any load condition
72Demand Controlled Ventilation6.2.7 Dynamic Reset
- What is it?
- Vary outdoor air intake to match current
population - How can it be done?
- Time-of-day schedules
- Occupancy (on-off) sensors
- CO2-based cfm/person sensing
- System ventilation efficiency (critical
ventilation reset)
73Demand Controlled Ventilation
- Does Std 62-2004 allow it?
- Implicitly YES
- Clarified somewhat in Interpretation 62-1999-33
- Presently
- Addendum 62n specifically allows DCV
74CO2-Based DCV
- How does CO2-based DCV work?
- Start with Ci Co G/Vo
- Tests show 80 of visitors are OK with human
bioeffluent odors at outdoor airflow Vo 15
cfm/p - Sedentary people generate CO2 at 0.0105 cfm/p
- If Co 300 ppm, Ci 300 10500/15 1000 ppm
- So, Ci - Co 700 ppm corresponds to 15 cfm/p in
offices
75CASE STUDYWashoe Medical Center, NevadaGas
filtration
- Helicopter landing pad
- O.A. filtration of Hydrocarbons, particulates
- Respiratory difficulties
- Chemical Filtration / HEPA particulate filtration
76 CASE STUDY Clinic OVO Montreal,
CanadaFertility clinic O.A./R.A. filtration
- Fertility Clinic
- Central AHU total filtration
- system
- 12,500 CFM O.A./R.A filtered
- MERV 8 /chemical filters / UV / HEPA
77CASE STUDYHIV Dental Clinic, Albany,
NYDedicated Filtration in Dental Surgery Areas
- Protect HIV patients from airborne contamination
- Filter Gases, Particulates, Biological
Contaminants - Maintain positive pressure 0.1 W.C. within
Dental Surgery Area.
78CASE STUDY Emergency 911 Center San
Francisco, CA.
- Objective Pressurization and Purification
- Equipment APS
? General Atmospheric Contaminants (SOX,,H2S,
NOX) ? Electrical Generator Atmospheric
Contaminants Diesel Emissions (Particulate / Gas)
Media Selection MM-1955 / 7000 Maintained Below
ISA G1 Severity-Level Requires Below 1 PPB on all
Gases Present in Class I Facilities
79CASE STUDY E-COMM Center, Vancouver,
CanadaEmergency Air Purification
- Location Vancouver, Canada
- Objective Purify contaminated O.A.
- Equipment USAH-406 filtration Bank
Key Contaminants ? CL2 ? NH3
Media Selection MM-9000 / 7000 A custom blend of
activated carbon impregnated with KOH.
80References
- Schoen, Larry ASHRAE Std 62, Ventilation for
Acceptable Air Quality. Boston Society of
Airchitects, Chapter of AIA, May 2004 - Vasselli, John Economics and Energy in
Buildings. Bynum Training Center, Carrier
Corporation, NOV 2006. - U.S. Environmental Protection Agency Office of
Mobile Sources. Air Toxics from Motor Vehicles.
February, 1995. - U.S. Environmental Protection Agency Office of
Mobile Sources. Environmental Fact Sheet -
Adopted Aircraft Engine Emission Standards.
August, 1994. - 1997 Current Market Outlook - World Market Demand
and Airplane Supply Requirements. Boeing, 1997. - Chang, K.M., The Integration of Airport Planning
and Environmental Assessment - A focus on Air
Quality Analysis, 1978. - Pant, Bhuvan C., Diesel Exhaust Irritants and
Odorants, Materials Research, Development and
Production Center, 1987. - Persily, Andrew ASHRAE Standard 62.1-2004
Introduction and Overview. ASHRAE Winter
Meeting, Orlando , FL, Feb 2005. - Carrier CorporationDemand Controlled
Ventilation System Design.Saving Energy Cost
while optimizing Indoor Air Quality. Syracuse
2001. - Stanke, Dennis. System Operation Dynamic Reset
Option, Standard 62.1-2004. ASHRAE Journal
December 2006 - ACGIH. 2001. Threshold Limit Values for Chemical
Substances and Physical Agents and Biological
Exposure Indices. American Conference of
Governmental Industrial Hygenists. - Purafil Canada Ltd. (Circul-Aire Inc.) Gas Phase
Filtration Technology and Solutions, 2005.