Protecting Human Health in the Built Environment

withEnhanced Air Filtration Devices

Gerald (Jerry) Lamping

ASHRAE Member

NAFA Member

EPA Master IAQ Class Member

Green Classroom Professional – USGBC

October 18, 2016 Alamo ASHRAE Meeting

ASHRAE History and Future• The ASHRAE was founded in 1894 at a meeting of engineers in New York City.

• Until 1954, the American Society of Heating and Ventilating Engineers (ASHVE);

• In 1954, American Society of Heating and Air-Conditioning Engineers (ASHAE).

• In 1959, ASHAE and the American Society of Refrigerating Engineers (ASRE) merged to form ASHRAE.

• In 2012, ASHRAE rebranded itself with a new logo and tagline:

"Shaping Tomorrow’s Built Environment Today

ASHRAE History and Future• The ASHRAE was founded in 1894 at a meeting of engineers in New York City.

• Until 1954, the American Society of Heating and Ventilating Engineers (ASHVE);

• In 1954, American Society of Heating and Air-Conditioning Engineers (ASHAE).

• In 1959, ASHAE and the American Society of Refrigerating Engineers (ASRE) merged to form ASHRAE.

• In 2012, ASHRAE rebranded itself with a new logo and tagline:

"Shaping Tomorrow’s Built Environment Today”

•In the Future, it may add the term Filtration & Air Cleaning (FAC) to its name

So Greetings toAlamo

ASH-RA-FACEEngineers

"Shaping Tomorrow’s Built Environment Today”

In the past, ASHRAE has been concerned about the

• Comfort of building occupants and

• Efficency of devices, equipment, and systems

In the future, “ASHRAFACE” will be also concerned about the

• Health of the building occupants and

• Productivity/performance of students, workers and public

"Shaping Tomorrow’s Built Environment Today”

In the past, ASHRAE has been concerned about the

• Comfort of building occupants and

• Efficiency of devices, equipment, and systems

In the future, “ASHRAFACE” will be also concerned about the

• Health of the building occupants and

• Productivity/performance of students, workers and public

While it may be difficult to talk about health issues and illness prevention due lack of knowledge and rules/regulations on making health improvement statements, HVAC people must tell about the benefits of FAC.

ASHRAE Standard for Ventilation for Acceptable

Indoor Air Quality, 62.1 -2016Since 1973, Standard 62 has been the

primary ASHRAE Clean Air and

Ventilation document:

1) reduce indoor contaminant sources

2) prescribe minimum outdoor airflow

rates for listed occupancy categories.

3) The standard allows three alternative

ventilation approaches.

Ventilation Rate Procedure (VRP)

Indoor Air Quality Procedure (IAQP)

Natural Ventilation Procedure (NVP)

ASHRAE Ventilation Rate Requirements

• ASHRAE minimum for Ventilation Rate (VRs) in offices is ~17 CFM/person

(Some IAQ organizations are calling for up to 50 cfm/person VR)

• Increased VRs, particularly in offices, may have many positive effects on occupant wellbeing

• Lower infection risk, less Sick Building Syndrome (SBS), reduced absenteeism, better productivity and decision making

• However, higher VRs will increase Ozone & Particulate Matter (PM) indoors

• Ozone & PM exposure = reduced health and productivity/performance!

Additional ASHRAE IAQ DocumentsA Position Document is a Board of Directors-approved document expressing the views of the Society on a specific topic pertaining to public policy.

• Airborne Infectious Diseases (PDF) (Updated May 2014)

• Environmental Tobacco Smoke (PDF) (Updated July 2016)

• Filtration and Air Cleaning (PDF) (Approved January 29, 2015)

• Indoor Air Quality (PDF) (Updated July 2014)

• Limiting Indoor Mold and Dampness in Buildings (PDF) (Updated January 2016)

ASHRAE Guide Books and Conferences

• ASHRAE Indoor Air Quality Guide (www.ashrae.org/FreeIAQGuidance)

• ASHRAE IAQ 2013: Environmental Health in Low Energy Buildings

• ASHRAE Annual Handbooks

http://www.rimbach.com/cgi-bin/Article/IHN/Number.idc?Number=118

Cleanroom standards are required for manufacturing of

electronics, drugs, food and beverage plants

Need a Clean Air Room Standard for Indoor Spaces at Class 6

Computers

Medicines

Indoor Space

Outside Air

Data CentersEntry Rooms

ISO 14644-1

Medical Devices

Semiconductors

Meat Processing

Needed: ASHRAE Standard for Filtration and Air Cleaning for Acceptable

Indoor Air Quality, 62.X -xxxx

EPA NAAQS PM StandardFor long-term effects of fine PM (PM2.5 ), EPA’s Clean Air Scientific Advisory

Committee (CASAC) recommended the primary health standard be tightened from

a current annual average of 15 µg/m3 to somewhere in the range of 11–13 µg/m3.

The EPA’s new standard 12 µg/m3 annual mean

With an annual standard of 12 µg/m3 , the EPA estimates the annual health benefits are

$2.3–5.9 billion, with costs of $69 million.

About 30% of the U.S. population lives in the 191

counties or parts of counties designated as

“nonattainment” for the current annual PM2.5 standard.

Weinhold B 2012. EPA Proposes Tighter Particulate Air Pollution Standards. Environ Health Perspect 120:a348-a349. http://dx.doi.org/10.1289/ehp.120-a348a

http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1289%2Fehp.120-a348a#r3

http://www.catf.us/resources/publications/files/SickOfSoot.pdf

Fresh Air is not always FreshALA’s latest State of the Air-2016 Report concludes the following

• more than half of all Americans—166 million people—live in counties where they are exposed to unhealthful levels of either ozone or particle pollution.

• More than 27.8 million people (8.9%) in the United States live in 17 counties with unhealthful levels of all pollutants measured in the report.

• Twenty-two of the 25 most ozone-polluted cities in the report – including Los Angeles, New York City, and Chicago – had more high ozone days on average.

Outside Air Is Not Always Clean

NAAQS Contaminants

Particle Matter • PM10,

• PM2.5 ,

• UFPM,

• Nano-PM

Ozone; Hot & Sunny Days

Water Vapor in Hot and Humid Climates

Other Gases; Sewer, Boiler Gas, Industrial

Chemical and Biological Threats; Pranksters

Source: ASHRAE 62.1-2007

Source: www.airnow.gov

EPA’s Air Quality Index

http://airnow.gov/index.cfm?action=aqibasics.aqi (Accessed 08/19/2013)

AQI Values Greater than 100

Number of days on which AQI values were greater than 100 during 2002-2010 in selected cities

http://www.epa.gov/airtrends/2011/graphics/figure06.gif

Saharan Dust travels across the Atlantic Ocean

Typical San Antonio Day

AQI 30

10 µg/m3

Air Quality Health Alert Day

in San Antonio

AQI 108

40 µg/m3

Outside Air in San Antonio

EPA Ozone StandardFor long-term effects of Ozone, EPA’s Clean Air Scientific Advisory Committee (CASAC) recommended the primary

health standard be tightened from a current annual average of 75 ppb to somewhere in the range of 60-70 ppb.

The EPA’s new Ozone standard is now 70 ppb

San Antonio could be in Non Attainment for O3

• Three Year Average of Fourth Highest Ozone Readings, 2014-2016

Monitoring Site Average Current 3-Year Average

• Camp Bullis C58 71

• Calaveras Lake C59 62

• San Antonio Northwest C23 68

• EPA’s NAAQS Limit for Ozone is now set at 70 parts per billion (ppb)

Source: http://www.tceq.state.tx.us/cgibin/compliance/monops/8hr_attainment.pl

Health Effects of Particulate MatterParticulate Matter (PM) has been identified as a air contaminant with significant public health impacts.

• In 1971, the US Total Suspended Particulate (TSP) was first regulated as a criteria NAAQS pollutant.

• In 1987 the regulation changed from TSP to respirable particulate matter less than 10 microns (PM10).

• In 1997, the regulation separated into a standard for PM10 and a standard for PM2.5.

• In 2012, driven by an increasing depth of health effects studies between PM10 and PM2.5, the PM2.5 standard was lowered from

an annual average concentration of 15 µg/m3 to 12 µg/m3.

• The current WHO and European PM2.5 Standard is 10 µg/m3.

Health Effects of Particulate & Ozone Pollution

Table 5 : Deaths attributable to AAP in 2012, by disease, age and sex

Disease Children < 5 years Men Women Total

ALRI 169,250 - - 169,250

COPD - 135,900 106,350 242,250

Lung cancer - 285,900 116,450 402,350

IHD - 606,350 472,450 1,078,800

Stroke - 540,600 542,150 1,082,750

Total 169,250 1,568,750 1,237,400 2,975,400

AAP : ambient air pollution ;

ALRI : acute lower respiratory disease ;

COPD : chronic obstructive pulmonary disease ;

IHD : ischemic heart disease.

Men and women are adults of 25 years and above.

WHO Report - Ambient air pollution:A global assessment of exposure andburden of disease

In 2012, the World Health Organization (WHO) report stated that

ambient air pollution from particulate matter was responsible for

• about 3 million deaths

Ambient air pollution: A global assessmentof exposure and burden of disease

Relationship between PM2.5 and mortality

EPA’s Health Effects Pyramid

Indoor air should

be at lowest

contamination

level

In 2012, the World Health Organization (WHO) report stated that

ambient air pollution from particulate matter was responsible for

•about 3 million deaths and

• 85 million DALYs.Disability Adjusted Life Years

Ambient air pollution: A global assessmentof exposure and burden of disease

Disability Adjusted Life Years (DALYs) provide an estimate of the total health burden and are a combined estimate of

• years of life lost (YLL) and

• years living with disability (YLD).

PM2.5 was the pollutant with the greatest DALY (700 DALYs lost per 100,000),

• second hand smoke (100 DALYs),

• radon-smokers (80 DALYs) and

• formaldehyde (35 DALYs).

The DALY for PM 2.5 is several times larger than the second hand smoke,

the indoor pollutant with the next highest ranking.

.

Disability Adjusted Life Years (DALYs)

Disability Adjusted Life Years (DALYs) provide an estimate of the total health burden and are a combined estimate of

• years of life lost (YLL) and

• years living with disability (YLD).

PM2.5 was the pollutant with the greatest DALY (700 DALYs lost per 100,000), • second hand smoke (100 DALYs),

• radon-smokers (80 DALYs) and

• formaldehyde (35 DALYs).

The DALY for PM 2.5 is several times larger than the second hand smoke,

the indoor pollutant with the next highest ranking.

PM 2.5 is identified by the J. M. Logue study* as the indoor air

contaminant with the greatest health impact in US buildings.

Disability Adjusted Life Years (DALYs)

* Environmental Health Perspectives, February 2012, v 120 no.2 pages 216-222

Disability adjusted life years (DALYs) are defined

by the World Health Organization as “years of healthy life lost”, and calculated as the sum of Years of life lost (YLL) and Years of life disabled (YLD).

Research Finds That Particle Size & Quantity Matters

• An increase in 10 micrograms per cubic meter of indoor course particle pollution, there is a 6 % increase in the number of days of cough, wheeze, or chest tightness in asthmatic children.

• An increase in 10 micrograms per cubic meter of indoor fine particle pollution, there is a

7 % increase in days of wheezing severe enough to limit speech.

Source: Johns Hopkins University School of Medicine February 2009

A decrease of 10 micrograms per cubic

meter of fine particle air pollution results in an

– increase in life expectancy

of 0.7 years

– in a 10% decrease in the risk

of premature death

Sources: Harvard School of Public Health, Jan. 2009

American Lung Association, Highlight of recent Research

on Particulate Air Pollution: Effects of Long Term

Exposure, www.lungusa.org Oct. 2008

Research Shows The Effects of Fine Particles

Buildings Located Near Major Highway (Keck School of Med.)

Childhood Incident Asthma and Traffic-Related Air

Pollution at Home and School By Rob McConnell, et al

•Results indicate that children exposed to higher levels of

traffic-related air pollution at school and home are at

increased risk of developing asthma.

•Almost 10% of public schools in California are located within

150 m of roadways with >25,000 vehicles daily.

•Students in urban areas in eastern U.S. cities are even more likely

… to attend schools near major highways.

•And one in three US public schools is within about 1,300 feet, or a

quarter mile, from a major highway.

• Environmental Health Perspectives • volume 118 | number 7 | July 2010

Invisible Particle Health Effects

Source: Pope and Dockery, 2006

http://www.noaca.org/pmhealtheffects.pdf

Health Effects Of Sub Micron Sized Particulate Matter (PM)

• Pulmonary inflammation initiating a

systemic response;

• Translocation of UFPM into the

blood circulation, leading to

interaction with endothelium and

white blood cells;

• Distribution to extra pulmonary

organs (e.g., liver, heart) thereby

inducing vascular effects and cardiac

events;

• Translocation of UFPM along

sensory neuronal pathways to the

CNS causing inflammation,

and activation of irritant receptors in

the conducting airways affecting

input to the automonic nervous

system.

Source: Assessment of Ambient UFP Health

Effects:Linking Sources to Exposure and

Responses in Extrapulmonary Organs : 2010

Grant EPA R827354, Günter Oberdörster et al,

University of Rochester; EPA PM Research Center

Health Risks of Indoor Exposure to Particulate Matter: Workshop Summary

available at http://www.nap.edu/23531

Studies have shown that PM2.5 and UFPs can reach the brain,

either via the nose and olfactory nerve (Oberdorster et al., 2004) or

via the lungs and systemic circulation (Peters et al., 2006).

Crossing from the systemic circulation into the brain involves direct transport or damage to the blood–brain barrier (Calderón-Garcidueñaset al., 2008).

Health Risks of Indoor Exposure to Particulate Matter: Workshop Summary

available at http://www.nap.edu/23531

Effects of PM exposure on the central nervous system.NOTE: BBB = blood-brain barrier; ROS = reactive oxygen species.

Studies have found that PM air pollution is harming brains of urban kids and have found that when airborne PM

and their components such as metals are inhaled or swallowed, they pass through damaged barriers, including

respiratory, gastrointestinal and the blood-brain barriers and can result in long-lasting harmful effects.

The results found that the children living in Mexico City had significantly higher serum and cerebrospinal fluid

levels of autoantibodies against key tight-junction and neural proteins, as well as combustion-related metals..

Calderon-Garciduenas notes that once there is a breakdown in the blood-brain barrier, not only will particulate

matter enter the body but it also opens the door to harmful neurotoxins, bacteria and viruses. "The barriers are

there for a reason. They are there to protect you, but once they are broken the expected results are not good,"

The results of constant exposure to air pollution and the constant damage to all barriers eventually result in

significant consequences later in life. The autoimmune responses are potentially contributing to the

neuroinflammatory and Alzheimer's and Parkinson's pathology they are observing in young urban children. While

the study focused on children living in Mexico City, others living in cities where there are high levels of PM.

Professor Lilian Calderon-Garciduenas(University of Montana) studies on PM

Significant health effects of Unclean Air

1. Aggravation of respiratory and cardiovascular disease*;

2. Decreased lung function*;

3. Increased frequency and severity of respiratory symptoms*;

4. Increased susceptibility to respiratory infections*;

5. Effects on the nervous system¥;

6. Cancer ¥;

7. Premature death ¥

American Academy of Pediatrics. Pediatric Environmental Health, 2012.

Kampa M and Castanas E, Environmental Pollution, 2008.

http://www.epa.gov/ttnatw01/3_90_022.html (Accessed 08/19/2013)

*Effects likely to occur in childhood and adulthood¥Effects likely to occur in adulthood, but associated with exposures in childhood

ASHRAE Position Document onFiltration and Air Cleaning (FAC)

• Filtration technologies, in which particles are removed by attaching them to the media (often called mechanical or media filters), have been documented to be capable in many cases of reducing particle concentrations substantially, including reductions from levels being above to levels being below the associated regulatory exposure limits for reducing health risk set by recognized cognizant authorities.

• Modest empirical evidence suggests that mechanical filters will have positive effects on health, especially for reducing adverse allergy or asthma outcomes...

• Models predict large reductions in morbidity and mortality associated with reduction of indoor exposures to particles from outdoor air, but these health benefits have not been verified empirically.

Invisible Particles In The Air

Current USA Filtration PracticeASHRAE 62.1-2013

MERV 8 before coil

Only one level of particle filtration and no level

of gas phase filtration for all HVAC systems

A MERV 8 Ain’t (isn't) Great

Source: Selecting Ventilation Air Filters to Reduce PM2.5. B Stephens, et al, ASHRAE Journal Sept 2016

3 Levels of Outside Air Quality - 4 Levels of Indoor Air Quality

Gas Phase Filters required in polluted areas for Clean Indoor air

http://www.freedom2choose.info/docs/EC_Standard_For_Ventilation.pdf

European Union Filtration Law

Classifications of Air Filters for Particle Matter

Portable Hand Held Particle Counter Needed to Measure PM Levels in Indoor Spaces

Six Channels of Particle Sizes from .3 to 10 Micrometers in diameter

Actual Experience in Removing Invisible Particles with Enhanced Air Filtration

Providing better thermal and air quality conditions in school classrooms would be cost-effective

by Pawel Wargocki and David P. Wyon, International Centre for Indoor Environment and Energy,

DTU Civil Engineering, Technical University of Denmark,

http://www.sciencedirect.com/science/article/pii/S0360132312002727

Particle

Size

Outside Air Injection Rate

Particles

Per

cm3

Without air

filter operation

With air filter

operation

ASHRAE Research Project RP 1257

Actual Experience in Removing Invisible Particles From Classrooms

Providing better thermal and air quality conditions in school classrooms would be cost-

effective by Pawel Wargocki and David P. Wyon, International Centre for Indoor

Environment and Energy, DTU Civil Engineering, Technical University of Denmark,

http://www.sciencedirect.com/science/article/pii/S0360132312002727

ASHRAE Research Project RP 1257

Particles In Classrooms

2,895

13,735

2,118

181

7,3965,127

663

169,339

167670

3,367

6,512

187,836

9,779

203,028260,521

120,352

1,663,402

10

100

1,000

10,000

100,000

1,000,000

10,000,000

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0

Particle Size, Micromenter

Part

./C

u F

t

Ten fold decease in Fine Particles after Air Cleaning in Room (G.A. Lamping 2010)

After Air

Cleaning

Before Air

Cleaning

Actual Experience in Removing Invisible Particles From Classrooms

Actual Experience Shows Test Score Benefits of Clean Air

School B had higher percentages (up to 4% higher) of students passing reading, writing and mathematics sections.

School B had 11% and 16% more students than School A obtaining the Commended Level on the reading and mathematics tests

(students correctly answered 90% or better of the TAKS questions). (G.A. Lamping 2012)

50556065707580859095

100

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2011 TAKS Tests Results

School B

School A

School A had ASHRAE Standard 62.1 Ventilation and Air Filtration Practice with CO2 Demand Control

School B had ASHRAE Standard 62.1 IAQ Procedure Filtration and Air Cleaning Practice with constant 7.5 CFM OA Ventilation

Actual Experience Shows Attendance Benefits of Clean Air

School A had slightly higher percentages (up to 0.4% higher) student attendance rates

School A had ASHRAE Standard 62.1 Ventilation and Air Filtration Practice with CO2 Demand Control

School B had ASHRAE Standard 62.1 IAQ Procedure Filtration and Air Cleaning Practice with constant 7.5 CFM OA Ventilation

School 10-11 11-12 12-13 13-14 Average

A 97.3 97.5 97.4 97.2 97.35

B 97.1 97.2 97.0 96.9 97.05

School Year Average Daily Attendance Rate, %

(G.A. Lamping 2016) http://www.neisd.net/athletics/PE/documents/DetectingAerosolsPPP.pdf

Filtration and Air Cleaning with Gas Phase Filtration Media

• Media is a combination of activated

carbon, and an activated alumina substrate

impregnated with sodium permanganate.

• By using these media in combination, the

removal of most irritant gases is achieved.

Air Cleaning in Practice – School Sustainability and Commercial Building Field Study Results

http://www.purafil.com/PDFs/Technical%20Papers/Commercial/Air%20Cleaning%20in%20Practice%20(IAQA%202009).pdf

Position Document: Airborne Infectious Diseases Engineering Controls to Reduce Infectious Microbe Transmission.

Strategies for Indoor Spaces

Dilution Ventilation Personalized ventilation Source capture Central system filtration Local filtration/cleaningDuct UVGI

The ASHRAE Position Document on Airborne Infectious Diseases January 2012

by the Society’s Airborne Infectious Diseases Position Document Committee. http://www.ashrae.org/about-ashrae/position-documents

Also the transmission of Shed and Re-suspended Particles

Enhanced Air Filtration Can Reduce the Risk of Flu Infection at Lower Cost

• Parham Azimi and Brent Stephens, Ph.D., Department

of Civil, Architectural and Environmental Engineering

at Illinois Institute of Technology have shown that

enhanced air filtration and cleaning can reduce the

risk of infection from the influenza virus.

• The annual costs for dilution and filtration are shown,

a break point is at ASHRAE’s Minimum Efficiency

Reporting Value (MERV) of 13.

• Annual costs are shown for one 24x24x1 filter.

Enhanced Air Filtration Can Reduce the Risk of Flu Infection at Lower Cost

Source: Parham Azimi and Brent Stephens, Ph.D., the Department of Civil, Architectural and Environmental

Engineering, Illinois Institute of Technology Chicago http://built-envi.com/

Costs for Dilution at

Different Climates

Costs for Filtration at

Different Levels

Harvard School of Public Health Study

• Recently, Kathleen Ward Brown, John D. Spengler and others from Environmental Health & Engineering Inc. and the Harvard School of Public Health, respectively, assessed the effectiveness of commercially available air filters to reduce the levels of asthma and allergy triggers in indoor environments.

• Their analysis found that an air filter valued at an ASHRAE MERV 12 and 13 level can effectively lower the indoor concentrations of asthma triggers and allergens by greater than 50% when installed in a central HVAC system.

• Annual operating costs for these air filters were calculated to be $70 and $80, respectively.

• Other studies throughout the world have demonstrated that improved filtration and air cleaning (FAC) practices are successful in reducing indoor levels of potentially harmful contaminants.

Impact of High-Efficiency Filtration Combined with High Ventilation Rates on Indoor Particle Concentrations and Energy Usage in Office Buildings

Michael S. Waring

Associate ProfessorDirector of Architectural Engineering Program

Civil, Architectural and Environmental Engineering at Drexel University

Indoor Environment Research Group (http://www.indoor-envi.com/)

Drexel Air Resources Research Laboratory (DARRL)

Building Science & Engineering Group (BSEG)

msw59@drexel.edu

National Air Filtration Association (NAFA)

Friday, August 28, 2015

NAFA + ASHRAE funded research project

National Criterion on Filtration and IAQ Procedure Recommended Enhanced/Best Practice ASHRAE 62.1 IAQ Procedure

NAFA “Best Practice Guidelines” for Commercial Spaces MERV 13 Not mentioned

NAFA “Recommended Practice Guidelines” for Schools MERV 8 MERV 13 Not mentioned

Texas - TX-CHPS-CRITERIA 2015 MERV 11 1 pt MERV 13 - 2pts MERV 15 Allowed

CALIFORNIA – CA-CHPS CRITERIA – 2014 MERV 13 MERV 15 Not Allowed

Washington Criteria for High-Performance Schools, 2015 MERV 13 or better Not mentioned

United States-US-CHPS CRITERION - 2014 MERV 11 MERV 13 Not Allowed

NORTHEAST CRITERIA (NE-CHPS) VERSION 3.O MERV 11 MERV 13 Not Allowed

European Standard for Ventilation – EN 13779-2007 Low PM outside air Medium PM outside air -----------

Air Filtration Requirement based on Particles(PM) in Outside Air MERV 8 MERV 13 Gas phase filter allowed

EPA - Energy Savings Plus Health: IAQ Guidelines for School Upgrades MERV 8 MERV11 to MERV 13Gas phase filter allowed

EPA - School Siting Guidelines: Sections 6, 8.1, and 8.2Evaluate the outside air quality at a particular

location for

Evaluating Impacts of Nearby Sources of Air Pollutioneither six Criteria Pollutants or Hazardous Air

Pollutants (HAPs) Gas phase filter allowed

LEED v4 - Enhanced indoor air quality strategies ------ MERV 13 Alternative Compliance Path

WELL Building Standard® Version 1.1 - 2014 MERV 13 Meet WELL Air Quality Standards Allowed

ASHRAE 62.1-2016 Ventilation for Acceptable Indoor Air QualityMERV 8 Minimum

Depending on Outside Air Quality Allowed

National Criterion on Filtration and Air Cleaning

(G.A. Lamping 2016)

ASHRAE IAQ Guide (Free)

www.ashrae.org/FreeIAQGuidance

Sponsored by

ASHRAE

American Institute of Architects,

U.S. Green Building Council,

Builders and Owners Management

Association International,

Sheet Metal and Air Conditioning

Contractors of North America,

U.S. Environmental Protection Agency.

Additional References on Impacts of Indoor Environments on Human Performance and Productivity

Source: and http://www.iaqscience.lbl.gov/

Impacts of Building Ventilation on Health and Performance

Indoor Dampness, Biological Contaminants and Health

Indoor Volatile Organic Compounds (VOCs) and Health

Impacts of Indoor Environments on Human Performance and Productivity

Benefits of Improving Indoor Environmental Quality

Scientific Findings Resource Bank

(IAQ-SFRB) Lawrence Berkeley National Laboratory