– 1970: Passage of the Clean Air Act. In the same year, both the U.S. Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) were formed.
1. What are the (5) primary elements of good IEQ? (PG: 6)
- Avoiding indoor air pollutants.
- Ventilation strategies.
- Physical comfort (4 categories), which depends on:
o Ergonomic comfort
o Thermal comfort
o Visual comfort
o Acoustical comfort
- Biophilia, which describes the innate human connection & need to experience natural habitats & systems (connection to the outdoors and natural lighting).
- Planning for health and well-being.
2. Discuss examples of how good IEQ benefits different stakeholder groups in terms of the 3E’s (environment, social equity, and economy). (PG: 7)
- Benefits to occupants (employees, building visitors, etc.)
o Improved long-term health.
o Decreased physical symptoms (i.e. headaches, fatigue, respiratory problems) & associated health care cost.
o Improved cognitive function and mood.
o Increased productivity.
- Benefits to building owner, or organization
o Reduced insurance liability costs.
o Decreased absenteeism.
o Increased productivity.
o Reduced regulatory inspection load.
o Less churn (changes in tenant occupancy).
o Improved community livability.
o Improved stakeholder relationships.
o Improved corporate profile.
o Better market position with “pro-green” consumers
3. Explain the different health risks associated with poor IAQ. (PG: 10)
- Acute Illness Clusters – some indoor air pollutants can directly cause acute health problems and illness.
- Sick building syndrome – EPA defines SBS as a set of symptoms that affect a substantial number of building occupants during the time they spend in the building that diminish or go away during periods when they leave the building, and that cannot be traced to specific pollutants or sources within the building.
- Building Related Illness – EPA defines as discrete, identifiable diseases or illnesses that can be traced to a specific pollutant or source within a building.
- Multiple Chemical Sensitivity – Unusually severe & chronic sensitivities or allergy-like reactions to many different types of pollutants.
- Body Burden – The persistent bioaccumulation of toxins in human bodies that present health issues for the human “host” of the toxins (individual immediately exposed to the toxins).
4. What are the linkages between good IAQ and materials choices? Are there other linkages between other building systems and IEQ? (PG: 23-25)
- Choose low or non-emitting building materials and finishes; request safety info and investigate what chemicals or particles make up the material.
o Low or non-toxic: materials that contain few carcinogens, irritants as demo’d by manufacturer through testing.
o Minimal chemical emissions: products with minimal VOCs; bonus for materials that maximize resources and energy efficiency, while reducing chemical emissions.
o Low VO C assembly: material can be installed with minimal VOCs producing compounds
o Moisture resistant: products or materials that resist moisture or inhibit the growth of biological contaminants in buildings.
o Healthfully maintained: materials or components and systems that require only simple non-toxic or low VOC methods of cleaning. Bonus for durable materials that require little care once installed.
o Contains safe components : precautionary approach when installing w/nanotechnology.
- Other linkages:
o Avoid conditions conductive to mold growth & other biological contaminants. (Cleaning)
o Emission & odor released from occupants. (Prohibit smoking & fragrance use in the workplace).
5. What are the sources of IAQ pollution? (PG: 12-13)
- (4) Outdoor sources:
o Outdoor air quality.
o Auto/transportation-related exhaust and fumes.
o Gases/vapor/smoke/dust from nearby const., operations, or industrial activities.
- (6) Indoor sources:
o Bldg. AC and air distribution system.
o Bldg. materials &/or furnishings.
o Const. & renovation.
o Occupant activities.
o Moisture/water intrusion.
o Lack of adequate ventilation.
6. Explain the hierarchy of solution for good IAQ. (PG: 23)
- Pathways and pressure govern the movement of air into, out of, and through a building and become avenues for the movement and distribution of pollutants and moisture. Eliminating or controlling their ability to move around, are the primary means of address IAQ.
- (4) Hierarchy of good IAQ solutions:
a) Avoiding/eliminating the source: select low-emitting VOC building materials and finishes
b) Isolating/sealing the source: segregate vent chemical storage areas, bathrooms, kitchens and office equipment room to an outside location
c) Ventilate: using ASHRAE Stds. 129-1997 & 62.2 – 2007. Supplying adequate outdoor ventilation air does dilute indoor air contaminants.d) Filter: include ways to capture particulates, mold spores and other biological pollutants. Maintenance plays a significant role in managing many allergens & irritants.
7. What is the difference between ventilation rate procedure and IAQ procedure? (PG: 25-26)
- Ventilation rate procedure: Acceptable IAQ is achieved by providing ventilation air of specified quality and quantity to the space.
o Carbon dioxide monitoring can help indicate the need for and timing of ventilation.
- IAQ procedure: Acceptable IAQ is achieved within the space by controlling known and specifiable (airborne) contaminants.
8. Explain the ventilation strategies, and list their similarities and differences. (PG: 27-29)
- Natural ventilation: requires a well designed layout and orientation of building in order to take advantage of:
o Stack effect or the flow of air resulting from warm air rising and naturally creating a positive pressure area at the top of a building and negative pressure area at the bottom of the building
o Wind driven pressure differentials – when wind attempts to equalize pressure differences that result from uneven heat distribution.
- Mechanical ventilation: consists of fans, louvers, and filters that circulate air through a system of ductwork.
o Delivery systems (2 Types):
- Constant volume (CV) system varies its supply and air temperature to match the reduction of space load during part-load operation to maintain predetermined space air temperature.
- Variable air volume (VAV) system varies its supply air-volume flow rate to match the reduction of space load during part-load operation to maintain predetermined space parameter, usually air temperature. Unlike CV systems, a VAV system reduces fan energy use when the supply volume flow rate is reduced or when there are more individual control zones.
o Delivery Design
o Under floor distribution introduces air through the plenum space under a raised access floor system through diffusers in the floor panels, rather than through a ducted overhead system.
o Displacement ventilation harnesses the natural buoyancy of heat to drive air flow. It also utilizes mechanical equip. to take advantage of this driving force.
o Filtration – low efficiency filters are generally used in HVAC systems to trap lint, dust and other large particles in order to keep from damaging the equipment.
- Hybrid, or Mixed-Mode, Ventilation: hybrid systems utilize both natural & mechanical ventilation to provide fresh air to spaces.
9. What are the elements of achieving good physical comfort? (PG: 44-51)
- The (4) elements of physical comfort include: thermal comfort, ergonomic comfort, visual and acoustic comfort.
A. Thermal Comfort (7 factors): Factors include temperature – air temperature, air mixing, air movement, relative humidity, activity level, clothing and thermal radiation.
- Temperature: Where air movement is virtually absent & when relative humidity can be kept at about 50%, the ambient temp. becomes the most critical factor for maintaining thermal comfort indoors.
- Humidity: when relative humidity is kept at 50%, office workers have few respiratory problems and generally feel better. Higher humidity makes the office feel stuffy. It contributes to bacterial and fungal growth, esp. in poorly ventilated and sealed buildings.
- Air movement: there must be air movement (oxygen and low carbon dioxide) to keep people alert and not lethargic or sleepy.
B. Ergonomic – refers to studies of the interaction between humans and the equipment they use.
- Disciplines include kinesiology, physiology / biomechanics, industrial and mechanical engineering, industrial design and psychology.
C. Visual – involves supplying high-quality light and the level of light appropriate to the tasks at hand, while creating visually interest and views.
- Eyestrain – inadequate or excessive light levels, poor ergonomic lighting design, and poor light quality (flicker, glare) can produce eyestrain in people.
- Seasonal Affective Disorder (SAD) is a form of depression thought to be related to light’s stimulus of the central nervous system that produces serotonin and / or the pineal gland which makes and releases melatonin.
- Occupant control – implement occupant control strategies allow people to easily control the light levels.
D. Acoustic – factors affecting acoustic comfort include level of background noise; reflection or absorption, qualities of the space, and sound transmission between spaces.
- Sources of sound problems include – office equipment, HVAC systems, outdoor noise, and voices in office space.
- Design solutions – ducts, fans; best solution is good design of the HVAC system, i.e. proper sizing and placement
- Noise masking includes: noise masking systems, installing ceiling tiles & carpet, cubical dividers over 5 feet tall and design strategies that avoid spill-over noise.
10. Describe the crossover between choices made in design that impact both energy and IEQ (e.g. lighting, HVAC, etc.). Refer back to Unit 3 (PG 10) to identify crossovers, and areas where tradeoffs may occur on a project. (PG: 50)
- ASHRAE 55-1992: prescribes an 80% comfort satisfaction rate by occupants at their specified temperature ranges.
- Humans expect to have an indoor environment with many factors within their comfort range, including temperature, air quality, surface temperature, humidity, air pressure, air velocity and acoustics. Comfort controls for light, temp., ventilation, & acoustics. In addition to the resultant change (in temp, light, noise, etc), there is a psychological benefit – humans feel more comfortable knowing that one has a certain level of personal control over their surroundings.
11. Define biophilia, and explain how it is similar or different to biomimicry. (PG: 51-52)
- Theory conceived by Edward Wilson at Harvard which proposes that humans have an innate biological need to be affiliated with processes and life forms, which is instrumental in human health and well-being.
- Biophilia is complementary to biomimicry, which looks at integrating natural systems into design processes.
- Biophilia is related to the aesthetics and psychological value of nature, while biomimicry focuses on using the functionality of nature as a design guide.
12. Explain the components of health and well-being, and describe how building features and strategies can negatively or positively impact the occupants’ health and well being. (PG 58)
a) Components of Health & well-being:
- Physical health & well being: design professionals typically focus on impacts to physical health: muscular-skeletal and respiratory concern, accident prevention and stress relief, carpal tunnel,
- correcting non-ergonomic, glass door collisions, IAQ issues related to respiratory conditions like asthma or anything that can cause sick building syndrome (SBS).
- Neuro-cognitive health and well-being: relates to a person’s memory, attention span, creativity, logical thought process, and flow.
- Psycho-social health & well being: related to emotional well-being, motivation, sense of belonging, satisfaction and social support – building blocks of commitment
- Sense of safety: can involve OSHA regulations and best practices; an environment that creates a sense of safety is important in reducing psychological stress and creating psychological comfort.
b) Positive impacts of building on occupants’ health & well being
- Ability by providing comfortable ambient condition by enabling individual control and adjustment of conditions and by reducing health and safety risks.
- Motivation by providing conditions that promotes positive affective functioning, psychological engagement, and personal control.
- Opportunity by providing equitable access to conditions that reduce health and safety risks, equitable access to amenities, and compensatory design options where inequities exist and are difficult to eliminate entirely.
c) Negative impacts of building on occupants health & well being:
- Negative impacts on ability to do work are associated with conditions that are uncomfortable, distracting, hazardous, or noxious.
13. Practice ‘pitching’ the health & well-being benefits of good IEQ to a pretend client. Then practice ‘selling’ the financial benefits of good IEQ.