Sources of Pollution Contributing to Indoor Air Quality

Environmental Factors

Thermal Comfort Impact on

Comfort, Health & Wellbeing and behaviour, where lower temperature can lead to aggression, while higher temperature can lead to both apathy and aggression. Supporting Reference

Motivation and performance improve when occupants are thermally comfortable. Warm discomfort has more negative effects on both attributes than cold discomfort.

Subjects’ heart rate, respiratory ventilation, end-tidal partial pressure of CO2 oxygen saturation decreases in a room temperature of 30°C vs. 22°C, implying negative affects on health and work effort.

Individuals are remarkably adaptable to temperature in a way that they are not, to air quality. (Cao and Wei, 2005)

(Cui et al., 2013)

(Lan et al., 2011)

(Alker et al., 2014) Study suggests that temperature is only one of three weather variables affecting people’s mood, daylight and length of nightime also play a role.

The change of human performance could also be explained by change of motivation rather than the change of temperature.

Small sample size (N=12).

Limitation / Bias / Argument

Noise 25% of noise perception is attributed to sound level while 75% are from personal and psychological factors, with 65% of variance in work performance, concentration and speech interference, being personal.

Performance drops 66% for ‘memory for prose’ tasks when individuals are exposed to varying types of background noise. (Oseland and Hodsman, 2018)

(Banbury and Berry, 1998) Prompts the question - does the extent of noise depend more on individual perception or the existing environment.

Small sample size (N=12).

The perception of thermal comfort still has a vidual satisfaction.

1.2 SOURCES OF POLLUTION CONTRIBUTING TO INDOOR AIR QUALITY

It is predominant to underline that indoor air quality of an environment is affected from contributions of both outdoor air sources of pollution and indoor sources of pollution, and consists of varying emission rates, and therefore it can be complex to determine where a specific pollutant is coming from. Table 1.2 presents a summary of air pollutants and their common sources, both indoor and outdoor. The highlighted sources are those that might be present within the building context yet to be explored in this report.

Category Pollutant Indoor Source Outdoor Source

Particulate Matter

Inorganic Air Pollutants

Chemical (Organic Air Pollutants)

Airborne Radiation

Biological Pollutants Particulate matter (PM) of different sizes • Combustion activities • Vacuuming & cleaning activities

Environmental Tobacco Smoke (ETS) • Smoking indoors • Components absorbed by indoor surfaces and later released • Air & road transport, combustion activities for industrial purposes; construction sites • Natural sources • N/A

Asbestos • Building materials prior to the year 2000 (now heavily regulated) • Natural deposits of asbestos minerals

Nitrogen Dioxide (NO2) Nitrogen Oxides (NOx) • Combustion activities • Burning of fossil fuels

• N/A • Motor vehicles, energy production, & industry

Carbon Monoxide (CO) Carbon Dioxide (CO2) • (Incomplete) combustion of fossil fuels • Human respiration • Burning wood, coal or gas • (Incomplete) combustion of fossil fuels • Burning of fossil fuels & industrial processes • Natural sources

Ozone (O3) • Sunlight reacting with pollutants in the air • By some devices such as laser printers, photocopiers & air cleaning appliances.

Volatile Organic Compounds (VOCs) • Construction & building products • • Furniture • Household consumer products

Semi-Volatile Organic Compounds (SVOC)

• Plasticisers (phthalates) • Flame retardants (PCBs, PBB) Formaldehyde • Building materials • chemical reactions • Sunlight reacting with pollutants in the air

• Combustion activities such as

• Pesticides

• N/A

Polycyclic Aromatic Hydrocarbons (PAHs) • Smoking, heating and cooking, burning of coal, oil, gas, rubbish, wood and other organic substances. • Incomplete combustion, waste incineration, industrial power generation, & vehicular and air • Natural sources

Radon • Through the ground, and cracks and fractures. • Water supplies can contribute to indoor levels. • Naturally occurring in certain regions in soil, rocks and water.

House dust mites • Bedding, carpets, mattresses, clothing, and soft furnishings • N/A

Moulds/fungi • Damp/moist surfaces/areas • Growing on food, plants and soil

Endotoxin • N/A • Natural environment

Pollen • Plants

Pet hair and dander • Wherever the animal (household pets or pests) may have been • Plants

• N/A