As topics go, indoor air quality is about as sexy as comfortable shoes. If in need of a conversation killer, it is as good as any.
So why read about it?
1. The average American spends at least 90% of her time indoors.
2. Indoor air has a powerful effect on your health (fatigue, allergies, respiratory illness including asthma, heart disease, cancer and other chronic conditions)
3. You are probably doing (or not doing) things that contribute to the problem.
4. Many of the fixes are relatively simple.
See my last post, Is Your Office Making You Stupid: The indoor pollution epidemic, for background on why indoor air pollutants are generally 2-5 times greater than outdoor levels.
A recent Consumer Reports national survey found that almost half of Americans use air fresheners at least once a week and 34% use candles or incense that often. Approximately 40% rarely or never clean their humidifier or kitchen range hood, despite daily use. 25% have never cleaned or replaced their furnace filter and nearly 20% still smoke at home or let others smoke there. Only 53% change the batteries on their CO alarms as directed.
All these things compromise the air you breath.
There are basically two approaches to indoor air quality. Eliminate sources of pollution and maximize ventilation with clean (or cleaned/filtered) outdoor air. Both provide incomplete solutions and therefore both are recommended.
The following is a brief summary of the most common indoor pollutants and what you can do about them.
Carbon Monoxide (CO) and Radon: The perfect assassins
Both gases are colorless, odorless and lethal.
Improperly maintained gas ranges, cooktops, furnaces, gas generators and wood, kerosene and propane heaters all can emit CO.
Radon, a radioactive gas, is the leading cause of lung cancer in nonsmokers and second leading cause overall. It permeates ground and water and seeps into the air.
Best Defense
· Annual inspection of all fuel-burning appliances including heating system
· Place a CO alarm on every level of dwelling and replace it every 5 years
· Perform a long-term (at least 90 days) radon test
o Cost - $20-$40 online
o 2-4 picocuries per liter of radon warrants treatment
Combustion Pollutants
These are gases or particles from gas ranges, cooktops, furnaces, wood-burning stoves and fireplaces.
Best Defense
· Whenever using gas range or oven run the exhaust hood
· Inspect gas stove burner ports regularly and clean clogged ports with needle
· Clean chimney annually
Cleaning Products
Cleanliness may be next to godliness but you might poison yourself getting there. The weaponry used in our culture’s war on dirt has disregarded the collateral damage.
For many urban dwellers, this category is complicated. Windows often remain unopened to prevent outdoor air pollutants from blanketing an apartment with black dust.
While this keeps the outdoor pollutants out, it increases the concentration of indoor pollutants. In this scenario you are dependent upon the building’s ventilation system, something most people don’t have a clue about.
No standards have been established for claims about cleaning products. While those labeled “green” are generally better, many are contaminated with questionable compounds. The most reliable products bear the Design for the Environment (DfE) label. These are screened by a third party and approved by the EPA. A new and more detailed EPA initiative launching in 2017 to replace the DfE is the Safer Choice label.
Fragrances are particularly problematic. They can contain 50-200 compounds many of which are often dangerous volatile organic compounds (VOCs). For example terpenes provide a pine or lemon scent and are associated with respiratory problems. They also can interact with ozone in the air and form formaldehyde, a carcinogen. Manufacturers are not required to list fragrance ingredients.
Best Defense
· Open a window (if possible) when cleaning
· Use fragrance-free products
· Look for the DfE or Safer Choice label
Volatile organic compounds (VOCs)
Cleaning supplies are one source of VOCs but there are many others found in homes.
o Paints and lacquers
o Paint strippers
o Varnishes and waxes
o Pesticides
o Building materials and furnishings
o Office equipment
o Moth repellents
o Air fresheners
o Dry-cleaned clothing
VOCs irritate the eyes, nose and throat. They cause headache, nausea and damage to the liver, kidneys and central nervous system. Some cause cancer.
Best Defense
· Ventilate when using products that release VOCs
· Follow instructions/warnings on label
· Never mix them
· Store in properly sealed containers away from living areas, ventilation systems and children
Air Fresheners
This oxymoronic VOC source is my favorite. The notion of spraying chemicals into a room to freshen the air has to be one of the greatest marketing victories of all time. As mentioned above, 50% of Americans attempt to improve their air with this practice.
Air fresheners have been found to contain phthalates, compounds associated with cancer and reproductive problems.
Best Defense – Don’t use them
Mold
As you know, mold is about humidity. It is a living thing and produces spores that float in the air, land on damp surfaces and grow. Molds cause hay fever symptoms, rashes and asthma attacks.
Ideal indoor humidity is considered to be between 30% and 50%. Below 30% dries the respiratory tract and above 50% grows mold.
Humidifiers and dehumidifiers can cause or cure this problem.
Inadequate maintenance of humidifiers allows them to spread mold and bacteria into the air. Humidifiers require daily emptying and frequent disinfecting. Dehumidifiers are less labor intensive but filters and tanks need periodic attention.
The room most vulnerable to mold is the bathroom.
Testing for mold is not recommended. Most devices are unreliable. Bad mold problems are visible and more subtle conditions can usually be detected by a musty odor.
Best Defense
· Proper maintenance of humidifiers and dehumidifiers as per owner’s manual
· Adequate bathroom exhaust fans
· Clean bathroom exhaust fans to prevent mold/bacteria – mold can grow in 24 hours on a wet surface
In the next installment of Building Health I will take up the question of testing indoor air and how to do your own inspection.