How concerned are you about your health? Have you ever tried to lose weight, eat healthy, and be active in order to prevent or eliminate any health risks? If so, you’ve left out one critical factor, AIR. Yes, you read it right; it’s the air that you breathe. All these factors contribute to your health and wellbeing. In order to be healthy, you need take control to eliminate or minimize the “bad” and bring in the “good”. This is still possible with your indoor air. So what’s in the air you’re breathing and how can you improve the indoor air quality (IAQ) around you?

 

What is in the air you’re breathing?

We are constantly exposed to the air that surrounds us regardless if we’re sleeping, working, playing, etc. It’s there 24/7 whether we like it or not. Worst yet, we unconsciously breathe it and bring it into our system with every breath we take. Indoor air pollutants are common but controllable. Sources of indoor air pollutants include, paints, lacquers, paint strippers, aerosol sprays, air fresheners, cleaning supplies, pesticides, building materials and furnishings, copiers, printers, correction fluids, carbonless copy paper, clothes, adhesives, permanent markers, and the list goes on. In other words, they are everywhere! All these Volatile Organic Compounds (VOC) release gases into the air and contribute to Sick Building Syndrome (SBS) and Building Related Illness (BRI) and are the primary cause of IAQ problems. Photo-ionization detectors (PID) are used “to get a simple measure of the joint exposures to several VOCs in indoor air” (Berglund, et al., 1997).

 

Volatile Organic Compounds (VOC)

Chemicals that emit gas are called VOC. Another common term, Total VOC (TVOC) is a combined variety of organic chemicals that emit gas. They are measured in micrograms per meter cubed (µg/m3) of air, parts per million (ppm), or parts per billion (ppb). Most buildings will have TVOC levels ranging from 100-500 µg/m3 (Aerias). Table 1, below, is used as a guide to compare TVOC results with its symptoms.

 

Table 1: TVOC and Symptoms

TVOC

Symptoms

< 200 µg/m3

No irritation or discomfort expected

200 – 3,000 µg/m3

Irritation and discomfort may be possible

3,000 – 25,000 µg/m3

Discomfort expected and headache possible

> 25,000 µg/m3

Toxic range where other neurotoxic effects may occur

Source from Aerias

 

Concentrations of many VOC are consistently (up to ten times) higher indoors than outdoors (US Environmental Protection Agency, 2010). Therefore, some VOC are regulated due to its short and long term affects on the health of humans. For example, the most common VOC is formaldehyde. On average, formaldehyde levels measured over a day in Canadian homes were 20-40 μg/m3 (16-32.5 ppb). Daily levels as high as 95 μg/m3 (77 ppb), however, have been recorded (Health Canada, 2009b). This chemical is strictly regulated by the Occupational Safety & Health Administration (OSHA) as it has been known to cause cancer. Table 2, below, lists a few common VOC along with the recommended exposure limit (REL) of the National Institute for Occupational Safety and Health (NIOSH), permissible exposure limit (PEL) of OSHA, identified symptoms if exposed to the chemical and some examples of products that contain the chemical.

 

Table 2: Common VOC

Chemical

Exposure Limit

Symptoms

A Few Examples

Acetone

C3H6O

NIOSH REL:


TWA 250 ppm (590 mg/m3)

 

OSHA PEL:


TWA 1000 ppm (2400 mg/m3)

eyes/nose/throat irritation, headache, dizziness, central nervous system depression

Nail polish remover

Paint thinners

Sanitary cleaner

Arsine

AsH3

NIOSH REL:


0.002 mg/m3 [15-minute]

 

OSHA PEL:


TWA 0.05 ppm (0.2 mg/m3)

headache, malaise, lassitude, dizziness, dyspnea, nausea, vomiting

 

lung & lymphatic cancer

Semi-conducting materials

Chemical warfare

Benzene

C6H6

NIOSH REL:


TWA 0.1 ppm ST 1 ppm

 
OSHA PEL:

TWA 1 ppm ST 5 ppm

eyes/nose/throat irritation, dizziness, headache, nausea, anorexia, lassitude

 

leukemia

Tobacco smoke,

Stored fuel

Paint supplies

Auto emission

Laboratory solvent

Formaldehyde

CH2O

NIOSH REL:

TWA 0.016 ppm

 

OSHA PEL:

TWA 0.75 ppm ST 2 ppm

irritation eyes/nose/throat, coughing, wheezing

 

nasal cancer

Carpet

Pill capsules

Disinfectant

Preservative in vaccines

Pressed wood

Hydrogen Sulfide

H2S

NIOSH REL:

10 ppm (15 mg/m3) [10-minute]

 
OSHA PEL:

20 ppm - 50 ppm [10-minute maximum peak]

eyes/nose/throat irritation, apnea, coma, conjunctivitis, photophobia, dizziness, headache, lassitude, irritability, insomnia

Crude petroleum

Natural gas

Hot springs

Volcanoes

Nitric Oxide

NO

NIOSH REL:

TWA 25 ppm (30 mg/m3)

 
OSHA PEL:

TWA 25 ppm (30 mg/m3)

unconsciousness, eye irritation, drowsiness, wet skin/nose/throat

Tobacco smoke

Vehicle exhaust

Vaccines

Phosphine

PH3

NIOSH REL:

TWA 0.3 ppm (0.4 mg/m3) ST 1 ppm (1 mg/m3)

 
OSHA PEL:

TWA 0.3 ppm (0.4 mg/m3)

nausea, vomiting, abdominal pain, diarrhea, chest tightness, dyspnea, pulmonary edema

Clothing

Microelectronics

Pesticide

Styrene

NIOSH REL:

TWA 50 ppm (215 mg/m3) ST 100 ppm (425 mg/m3)

 
OSHA PEL:

TWA 100 ppm C 200 ppm 600 ppm (5-minute maximum peak in any 3 hours)

eyes/nose irritation, headache, lassitude, dizziness, confusion, malaise, drowsiness, narcosis, reproductive effects

Synthetic rubber

Insulation

Fiberglass

Pipes

Auto and boat parts

Food containers

Carpet backing

Toluene

C7H8

NIOSH REL:

TWA 100 ppm (375 mg/m3) ST 150 ppm (560 mg/m3)

 
OSHA PEL:

TWA 200 ppm C 300 ppm 500 ppm (10-minute maximum peak)

eyes/nose irritation, lassitude, confusion, euphoria, dizziness, headache, dilated pupils, lacrimation, anxiety, muscle fatigue, insomnia, paresthesia, dermatitis, liver/kidney damage

Feedstock

Paint solvents

Gasoline

Silicone sealants

Printing ink

Adhesives

Disinfectants

Xylene

C6H4C2H6

NIOSH REL:

TWA 100 ppm (435 mg/m3) ST 150 ppm (655 mg/m3)

 
OSHA PEL:

TWA 100 ppm (435 mg/m3)

eyes/nose/throat/skin irritation, dizziness, excitement, drowsiness, corneal vacuolization, anorexia, nausea, vomiting, abdominal pain, dermatitis

Plastic bottles

Polyester clothing

Cleaning agents

Paint thinner

Paints & varnishes

Gasoline

Concrete sealers

TWA = Time Weighted Average

 

Sick Building Syndrome (SBS) and Building Related Illness (BRI)

Long term exposure to VOC contributes to SBS and BRI. Based on the US Environmental Protection Agency (1991), SBS and BRI are compared in Table 3 below:

 

Table 3: Comparison between SBS & BRI

 

Sick Building Syndrome (SBS)

Building Related Illness (BRI)

Definition

An illness temporarily associated with an occupant’s presence in a building caused by indoor air pollutants.

A diagnosable illness caused by an identified agent in the indoor air.

Symptoms

Headaches

Eye, nose, throat irritation

Dry cough

Dry or itchy skin

Dizziness

Nausea

Fatigue

Cough

Chest tightness

Fever

Chills

Muscle aches

Cause

Unknown

Identified

Symptom after leaving building

Relief

Require prolong recovery time

 

Photo-ionization Detector (PID)

A PID is commonly used to measure TVOC mainly because it is the most efficient on the market. It provides instant and continuous readings to the user. However, if there’s a rapid temperature change or humidity level is high, the reading maybe affected.

PID is great for indicating the presence of VOC but it doesn’t identify the exact type of VOC. If a TVOC reading is 200 µg/m3 and increased to 300 µg/m3 the next month, it’s impossible to say the increase was due to formaldehyde. It’s also impossible to identify what combination of VOC made up the TVOC reading.

Ideally, measuring the exact type of VOC and monitoring it is a better practice. Unfortunately, this is not the case due to very high cost and convenience. In the short term, having one instrument to provide a TVOC reading as well as other sensors is less expensive and easier for the technician than to have to carry multiple units for each type of chemical. However, in the long term, if a high reading was detected, it will cost more to solve the problem since the type of VOC needs to be identified before a solution gets established. The technician would need to make a lot of assumptions and do a lot of trial and error runs which could take forever or a more simple method would be to analyze the air samples. Depending on the seriousness of the situation, other costs that get lumped into the problem are evacuation of the occupants, specific VOC detector(s) needs to be purchased, delays of other projects, and the time of all the individuals involved.

 

Common buildings that should monitor their IAQ include:

  • Hospitals
  • Scientific facilities eg. laboratories
  • School
  • Commercial buildings
  • Warehouses
  • Industrial buildings
  • Parkades
  • Repair shops
  • Food plants
  • Salons & spas
  • Manufacturing Plants
  • Medical Offices
  • Construction sites
  • Transportation facilities
  • And many more…

 

How can you improve the IAQ around you?

Now that you have an understanding about the air that you’re breathing, you can take can control and improve your IAQ. Here are some preventatives that you can do to minimize your health risk:

  • If using products that have high fume make sure there is proper ventilation. Outdoor air can dilute the chemical level.
  • No smoking indoors or near windows or doors. Tobacco smoke gets absorbed by furniture, carpets, curtains, etc. and takes a long time to be desorbed.
  • Chimney needs to be cleaned and clear of obstructions.
  • Don’t idle vehicles or gas powered equipment indoor (eg. garage) or near windows or doors.
  • For building & household products, use “green” or “environmentally friendly” options.
  • If possible, wash and air out products (eg. drapes, clothing, sheets) containing any VOC before bringing indoor.
  • Buy limited quantities to avoid having leftovers for storage.
  • Safely dispose partially full containers of old or unneeded chemicals.
  • Prevent moisture build-up inside and make sure water leaks are cleaned up rapidly.
  • Keep humidity levels below 60% (Aerias) by purchasing a dehumidifier. High humidity encourages off gassing.
  • Read labels and use as directed.

 

For suggestions on gas detection systems, indoor air quality monitors and calibration, please visit www.critical-environment.com.

 

References
Aerias. “VOCs: A Major Contributor to Indoor Pollution”. Retrieved June 8, 2010 from http://www.aerias.org/DesktopModules/ArticleDetail.aspx?articleId=131.
Berglund, et al. (1997). “Total Volatile Organic Compounds (TVOC) in Indoor Air quality Investigations”. Retrieved June 8, 2010 from http://www.inive.org/medias/ECA/ECA_Report19.pdf.
Centers for Disease Control and Prevention. (2010). “NIOSH Pocket Guide to Chemical Hazards”. Retrieved June 8, 2010 from http://www.cdc.gov/niosh/npg/default.html.
Environment Canada. (2010). “Clean Air Online”. Retrieved June 7, 2010 from http://www.ec.gc.ca/cleanair-airpur/Home-WS8C3F7D55-1_En.htm.
Gilbert, Nicolas. (2005). “Proposed residential indoor air quality guidelines for formaldehyde”. Retrieved June 3, 2010 from http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/air/formaldehyde/in-formaldehyde-eng.pdf.
Health Canada. (2006). “Residential Indoor Air Quality Guideline: Formaldehyde”. Retrieved June 4, 2010 from http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/air/formaldehyde-eng.pdf.
Health Canada. (2009a). “Formaldehyde - Pollutants from Household Products and Building Materials”. Retrieved June 3, 2010 from http://www.hc-sc.gc.ca/ewh-semt/air/in/poll/construction/formaldehyde-eng.php.
Health Canada. (2009b). “It's Your Health: Formaldehyde and Indoor Air”. Retrieved June 4, 2010 from http://www.hc-sc.gc.ca/hl-vs/alt_formats/pacrb-dgapcr/pdf/iyh-vsv/environ/formaldehyde-eng.pdf.
US Environmental Protection Agency. (1991). “Indoor Air Fact Sheet No. 4 (revised) – Sick Building Syndrome”. Retrieved June 8, 2010 from http://www.epa.gov/iaq/pubs/sbs.html.
US Environmental Protection Agency. (1994). “Indoor Air Pollution: An Introduction for Health Professionals”. Retrieved June 8, 2010 from http://www.epa.gov/iaq/pubs/hpguide.html.
US Environmental Protection Agency. (2010). “An Introduction to Indoor Air Quality: Volatile Organic Compounds (VOCs)”. Retrieved June 8, 2010 from http://www.epa.gov/iaq/voc.html.
World Health Organization. (1989). “International Programme on Chemical Safety (IPCS): Environmental Health Criteria 89: Formaldehyde”. Retrieved June 2, 2010 from http://www.inchem.org/documents/ehc/ehc/ehc89.htm.