INDOOR AIR QUALITY

“Quality” Indoor Air

Good Indoor Air Quality (IAQ) depends upon...

Proper circulation Age of the building Regular maintenance Filtration Humidity levels

Indoor air in schools

One out of every thirteen school-aged children suffer from asthma

Every year, more than 10 million absentee days are accumulated on account of airborne related illnesses

EPA study in 2000 determined 50% of nation’s schools had improperly maintained equipment

Student test performance

Effect of outdoor air supply rate and filtration Speed of 4 of 7 tests performed improved

significantly when outdoor air supply rate increased

No sig. effect on test scores Effect of moderately raised temperatures

When temps reduced from 25 to 20 degrees Celsius, performance (speed) improved in 2 numerical and 2 language based tests

Effect of particle filtration So significant effects on performanceWargocki and Lyon, 2006. Wargocki et al., 2007.

Indoor Air Pollutants

Radon Carbon Monoxide Ozone Tobacco Smoke Volatile Organic Compounds (VOC’s) Toxic Materials – Asbestos, Lead Biological Aerosols (Bioaerosols)

Bioaerosols

Defined as... - Any airborne molecule that is biological in

origin

can be in the form of gases, vapor, or large particulates.

can also be microorganisms themselves- Fungi, bacteria, viruses, protozoans

Bioaerosols

SOURCE EXAMPLES OF BIOAEROSOLS

Bacteria Legionella, Actinomycetes

Fungi Histoplasma, Alternaria, Pencillium, Aspergillus, Stachybotrys, aflatoxins, aldehydes, alcohol

Protozoans Naegleria, Acanthamoeba

Viruses Influenza

Algae Chlorococus

Green Plants Ambrosia (ragweed) pollen

Arthropods Dermatophagoides (dust mites) feces, Cockroaches

Mammals Dog or cat danderSource: http://www.state.nj.us/health/eoh/peoshweb/bioaero.htm

Aerial Microbiological Contamination

Study conducted in Italy, Daccarro et al. 2003, looking at airborne microbial communities in gyms

Found a higher abundance of “Staph” in the gym compared with outdoors

Also, 38 fungi taxa in gyms and 30 outdoors

Classroom activities

Growing Airborne Microbes Comparing different areas of the scholastic

environment Petri dishes Agar medium

Particulate traps Wire hangers, nylon, and petroleum jelly

Legionella

Genus of bacteria

Legionnaires disease

Flu-like symptoms

Domestic hot-water systems and cooling towers

Staphlococcus

Most species harmless

Food poisoning

More recently, human infections

Actinomycetes

Very common: 1-20 million/ g of soil

Look much like fungi but are bacteria

Tuberculosis

Histoplasma

Histoplasmosis

Primarily effects lungs

Common in immunodeficent individuals

Alternaria

Mostly plant pathogens

Allergen to humans

Pencillium

Commonly known as moulds

Main cause of food spoilage

Produce mycotoxins

Many practical applications

Aspergillus

Another common mould

Some species produce aflatoxins

Also, many practical applications

Stachybotrys

Black mold

Moist areas

Wide range of symptoms

Extended exposure: very severe symptoms

Dermatophagoides (dust mites)

One of the main causes of asthma

Fecal matter higher allergenic

Unfortunately, no way to avoid...FOUND EVERYWHERE