Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 1 Indoor Air Quality

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1 INDOOR AIR QUALITY OPR IAQ: one of the key outcomes along with thermal comfort of a climate control system Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 1 Indoor Air Quality We are completely submerged in this ocean of air and we are completely dependent upon it as any fish is upon the sea. Our relationship with it is very complex the air is also the habitat of the respiratory system, including the sense of olfaction James Marston Fitch American Building: The Environmental Forces That Shape It Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 2 1

2 IAQ We ll consider Why? Why should an architect worry about IAQ? What? What is indoor air quality? How? How is IAQ addressed during design? Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 3 Design Context Design for IAQ is related to, but generally independent of, design for thermal comfort (thermal comfort IAQ; IAQ thermal comfort) IAQ is an important issue in building design and operation (with lots of concerns, fears, false alarms, real problems, quacks, and experts) IAQ must be first addressed in pre-design OPR development (building codes tend to be minimal-solutionoriented rather than problem-defining) IAQ is an interdisciplinary concern IAQ is one part of IEQ (indoor environmental quality) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 4 2

3 Why Worry About IAQ? An architect s ethical responsibility to cause no harm IAQ complaints and news stories can be reputation-killers for all involved parties IAQ lawsuits have been filed, are pricey, and make compelling news stories IAQ is an interdisciplinary design issue (ideally with the architect in the lead) To address green design outcomes (LEED, ) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 5 Bad Press Florida in a hot, humid climate Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 6 3

4 Bad Press Florida (continued) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 7 Bad Press Nationwide in a temperate climate Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 8 4

5 Some IAQ Terminology Sick Building Syndrome A building whose occupants experience acute health and/or comfort effects that appear to be linked to time spent therein, but where no specific illness or cause can be identified. Complaints may be localized in a particular room or zone, or may spread throughout the building. Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 9 Some IAQ Terminology Building Related Illness Diagnosable illness whose cause and symptoms can be directly attributed to a specific pollutant source within a building (e.g., Legionnaire's disease, hypersensitivity, pneumonitis). Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 10 5

6 IAQ Terminology for Design Acceptable Indoor Air Quality Air in which there are no known contaminants at harmful concentrations as determined by cognizant authorities and with which a substantial majority (80% or more) of the people exposed do not express dissatisfaction. [ this defines acceptable IAQ ] ASHRAE Standard Ventilation for Acceptable Indoor Air Quality Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 11 Two Sides to Acceptable IAQ HEALTH COMFORT Air in which there are no known contaminants at harmful concentrations as determined by cognizant authorities and with which a substantial majority (80% or more) of the people exposed do not express dissatisfaction. ASHRAE Standard Ventilation for Acceptable Indoor Air Quality Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 12 6

7 Acceptable IAQ per ASHRAE Involves a health component that is addressed quantitatively from a medical perspective (as it must, due to the nature of the concern) This aspect of acceptable IAQ deals with contaminants that usually cannot be detected (or evaluated) by occupants Involves a comfort component that is addressed qualitatively via occupant opinions (as it must, due to the nature of the concern) This aspect of acceptable IAQ deals with characteristics of air quality that can be sensed (and evaluated) by occupants Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 13 Common Health-Related Contaminants Carbon dioxide (CO 2 ) Carbon monoxide (CO) Radon Ozone Formaldehyde Asbestos Sulfur dioxide VOCs (volatile organic compounds) Particulates Molds, spores Viruses Dust Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 14 7

8 Health Effects of Common Contaminants Carbon dioxide (CO 2 ): displaces oxygen (drowsiness or worse) Carbon monoxide (CO): toxic substance (quickly fatal) Radon: carcinogen (long-term impacts) Ozone: reactive agent (lung irritation, trigger for asthma) Formaldehyde: irritant (eye and throat); possible carcinogen Asbestos: carcinogen (long-term impacts) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 15 More Contaminants & Health Effects Sulfur dioxide: eye and throat irritation VOCs: wide range of possible effects (from a broad family of compounds) Particulates: eye and throat irritation Molds, spores: irritations, allergies, toxic reactions Viruses: transfer of illnesses Dust: eye and throat irritation Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 16 8

9 Comfort-Related Contaminants Odors Body odor Perfume Cologne Pizza?? (pick your own) Dust Water vapor Should be dealt with under thermal comfort (it affects the perception of odors, but is not itself a contaminant) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 17 Contaminant Sources Occupants Produce CO 2, odors, bacteria/viruses, skin cells, Furnishings Source of outgassing (of VOCs, formaldehyde, ) Construction and finishing materials May produce outgassing (VOCs), traces of lead, asbestos diffusion, Processes (such as printing, cooking, welding and construction activities) Produce dust, paint fumes, vapors, ozone, Exterior environment May contain radon, smog, dust, odors, Cleaning May release VOCs or other chemical compounds, stir up dust Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 18 9

10 IAQ Control Approaches Dilution via ventilation Reducing contaminant concentrations by infusing polluted air with cleaner (outdoor) air Passive ventilation = an architectural design strategy Active ventilation = a mechanical design strategy Dilution via filtration Reducing contaminant concentrations by removing contaminants (a mechanical design strategy) Dilution via exclusion (source control) Reducing contaminant concentrations by limiting their production and/or flow into a space) Materials selection = an architectural design strategy Spot exhaust = a mechanical design strategy Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 19 Ventilation In the IAQ context ventilation means introducing clean air (outdoor air and/or well-filtered air) Ventilation requirements are addressed squarely by ASHRAE Standard for non-residential 62.2 for residential Future 62.x for special occupancies?? Ventilation rate is expressed as CFM per person or CFM per square foot CFM = cubic feet per minute (an airflow rate) Ventilation has serious energy use (and ongoing cost) implications since it brings hot or cold air into a presumably thermally-comfortable building Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 20 10

11 Ventilation Examples Active Passive Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 21 ASHRAE Standard 62 A fairly thin, yet controversial, standard (not a guideline). Considered too complicated by many. Considered too demanding by many and too lax by some. Provides prescriptive and performance compliance paths. Indoor Air Quality Guide Released by ASHRAE, AIA, USGBC, etc. Essentially a user s manual for good IAQ Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 22 11

12 OLD ASHRAE Standard 62.1 Provided One-Step Ventilation Requirements Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 23 NEW ASHRAE Standard 62.1 Provides Two-Step Ventilation Requirements Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 24 12

13 Passive Ventilation Design Issues (They re All Architectural) Source of fresh air (not always trivial see sign) Delivery of fresh air to space Ventilation system choice Air flow opportunities Control strategy System on/off control System modulation Can one person s actions or inactions destabilize the ventilation system? LEED Certified Building, Portland, OR Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 25 Active Ventilation Design Issues (Shared Responsibility) Source of fresh air (architectural/mechanical) Delivery of fresh air to space HVAC system choice (mechanical) Air delivery devices (mechanical) Control strategy (mechanical) Continuous ventilation with on-off control Demand controlled ventilation with proportional control commonly using CO 2 sensors with 1000 ppm as a typical target Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 26 13

14 What s With CO 2? CO 2 is an indoor air contaminant (produced by people and other things) It is fairly easy and economical to measure CO 2 Other contaminants are difficult and/or expensive to measure Thus, CO 2 is often used as an indicator of ventilation effectiveness and as a surrogate for contaminants in general Often used as an IAQ warning signal With 1000 ppm as a typical concern threshold Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 27 Filtration Filtration is essentially the process of straining air to remove pollutants Is addressed by ASHRAE Standard 62 The designer must match filter(s) to contaminant(s) Run-of-the-mill filters (physical screening action) These use MERV ratings (Minimum Efficiency Rating Value) The higher the MERV, the better the filter HEPA filters (High Efficiency Particle Arrestance; really good filters) Electrostatic filters (use opposing electrical charges) Adsorption/absorption filters (use chemical action) Filters are a fundamental part of an HVAC system Predominantly a mechanical systems design issue, with energy implications (due to pressure drop as air flows through the filter) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 28 14

15 Panel Filters HEPA Bag Electrostatic Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 29 Air Filter Performance Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 30 15

16 Source Control Is (in my opinion) the most logical IAQ approach (it addresses contaminants before they are a problem although there are limits to applicability you can t source control occupants) Not really addressed in ASHRAE Standard 62 For information look to green design guides (for materials) and specialty equipment manufacturers (for hoods; spot exhaust) Predominantly an architectural design issue (or an architectural coordination concern) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 31 Source Control - Mechanical laboratory fume hood kitchen exhaust fan Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 32 16

17 Source Control - Architectural selection of materials Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 33 Source Control - Paints Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 34 17

18 Source Control - Millwork Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 35 Epilogue: Why Worry About IAQ? Call v. Prudential (a critical lawsuit) This was the first major IAQ-related case argued before a jury. Although the case was settled (for a sum rumored to be in the multimillion dollar range) before a verdict was reached, Call generated important IAQ related law. Claims by the plaintiffs charged acts of negligence, including: 1) using building materials that emitted formaldehyde or other noxious substances 2) failure to warn them that the building was unsuitable for occupancy due to the noxious fumes and chemicals invading the premises 3) failure to supply sufficient fresh (outside) air to the building 4) failure to heed reports of tight building syndrome (TBS) and sick building syndrome (SBS) 5) failure to convey information about the health effects of tight building syndrome and sick building syndrome. Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 36 18

19 Why Worry? (continued) Call v. Prudential The owner of the building with the alleged IAQ problems was Prudential Insurance Company. It was named in the suit together with the management company, architect, engineer, general contractor, the companies that installed the HVAC components, and the company that built the floor where the problems originally occurred. The Call case extended the chain of liability for problems with the HVAC system not only to the manufacturers and sellers of the system, but to everyone involved in the design and construction of the system, architects, engineers, installers, and anyone else who might have been involved. A rational person might conclude: when it comes to IAQ problems, there are no innocent bystanders. Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 37 IAQ IEQ IAQ = indoor air quality focus as described above IEQ = indoor environmental quality focus includes IAQ thermal comfort visual comfort acoustical comfort Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 38 19

20 dust mite (not to scale): an indoor air contaminant (particulate) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 39 radon potential Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 40 20