Indoor Air Quality

Starting Point:  When complaints of indoor air quality are non-specific, placement of a Q-trak monitor is often recommended as an inexpensive starting point for the response action.  A Q-trak measures and records concentrations and trends in carbon monoxide, carbon dioxide (CO2), temperature and relative humidity.  When CO2 concentrations exceed 1,000 ppm, complaints of stuffy air, itchy eyes, etc., will ensue.  Elevated CO2 levels are most often traced to problems with the building's heating, ventilation and air-conditioning (HVAC) system.  The most common problem:  Pre- and inner filters that have exceeded their useful life.  Ellis often inspects HVAC units as a normal part of its investigation.  

Depending on the results of its initial investigation, Ellis may also recommend and perform testing for the following contaminants:

  • Airborne Asbestos and/or Lead:
    Airborne asbestos and lead are common hazards that may be produced during and after building renovation/demolition activities when the work is performed improperly by non-licensed personnel.  Because emissions are strictly regulated by the EPA and OSHA, improper disturbance can result in significant fines and penalties.   Airborne lead and asbestos may be emitted in the absence of proper engineering controls installed by licensed abatement contractors.  On behalf of a building Owner, Ellis provides initial testing of building materials, procures removal quotes from qualified contractors, and manages the project to completion. 
  • Airborne Bacteria
    In indoor environments, bacteria are present in air and on surfaces. High levels of bacteria concentrations indoors are an indication of high occupancy rate, poor ventilation, or poor building maintenance. Similar to mold, some bacteria are associated with water-damaged building materials.  While bacteria do not receive as much publicity as mold when it comes to indoor air quality, they can represent a health hazard. Some are serious human pathogens and others (especially the gram-negative bacteria) produce toxic compounds (endotoxins) from the outer membrane of their cell wall.
  • Airborne Mold
    Molds are very common in buildings and homes. Mold will grow in places with a lot of moisture, such as around leaks in roofs, windows, or pipes, or where there has been flooding. Mold grows well on paper products, cardboard, ceiling tiles, and wood products. Mold can also grow in dust, paints, wallpaper, insulation, drywall, carpet, fabric, and upholstery.  The most common indoor molds are Cladosporium, Penicillium, and Aspergillus.  Mold is found both indoors and outdoors. Many building materials provide suitable nutrients that encourage mold to grow. Exposure to damp and moldy environments may cause a variety of health effects. 
  • Allergens
    Allergens are common in indoor office and home environments. Some common indoor allergens include dog/cat dander, rat/mice droppings, cockroach, dust mites. Exposure to these contaminants may impact susceptible individuals.
  • Carbon Dioxide (CO2), Carbon Monoxide (CO)
    Carbon dioxide is a normal constituent of human breath.  Outdoor levels typically range from 300 to 400 parts per million (ppm). Although not dangerous, at above 1,000 ppm complaints of “stuffy air” will increase. Carbon dioxide is dangerous at concentrations approaching 5,000 ppm.  Carbon monoxide is a colorless, odorless, tasteless gas produced by burning gasoline, wood, propane, charcoal or other fuel. Improperly ventilated appliances and engines, particularly in a tightly sealed or enclosed space, may allow carbon monoxide to accumulate to dangerous levels (>25 ppm). 
  • Formaldehyde
    Formaldehyde is a colorless, strong-smelling chemical used in building materials and many household products, and as a preservative in funeral homes and medical labs. It is a known carcinogen. 
  • Nitrogen Dioxide (NO2)
    Nitrogen Dioxide (NO2) is one of a group of highly reactive gases known as oxides of nitrogen or nitrogen oxides (NOx). Other nitrogen oxides include nitrous acid and nitric acid. NO2 is used as the indicator for the larger group of nitrogen oxides.  NO2 primarily gets in the air from the burning of fuel. NO2 forms from emissions from cars, trucks and buses, power plants, and off-road equipment. Breathing air with a high concentration of NO2 can irritate airways in the human respiratory system. Such exposures over short periods can aggravate respiratory diseases, particularly asthma, leading to respiratory symptoms (such as coughing, wheezing or difficulty breathing), hospital admissions and visits to emergency rooms.
  • Ozone (O3)
    Ozone is a molecule composed of three atoms of oxygen. When inhaled, ozone can damage the lungs. Relatively low amounts can cause chest pain, coughing, shortness of breath and throat irritation.
  • Particulate Matter (PM2.5-PM10)
    Nuisance dust includes dust particles greater than 10 microns in size. Respirable dust (<5 microns) is more dangerous since it can be drawn deeply into the lungs.
  • Radon
    Radon is a naturally-occurring radioactive gas that can cause lung cancer. Radon gas is inert, colorless and odorless. Breathing radon over time increases your risk of lung cancer. Radon is the second leading cause of lung cancer in the United States.  Radon is found naturally in the atmosphere in trace amounts. Outdoors, radon disperses rapidly and, generally, is not a health issue. Most radon exposure occurs inside homes, schools, and workplaces. Sulfur Dioxide (SO2)
  • Sulfur Dioxide
    Sulfur dioxide is a gas. It is invisible and has a sharp smell similar to burning matches. It reacts easily with other substances to form harmful compounds, such as sulfuric acid, sulfurous acid and sulfate particles.
  • Ultra-fine Dust Particles 
    Ultra-Fine Particles (UFPs).  Recent studies indicate that office copying equipment and laser printers can be potential emitters of ultra-fine particles (UFPs).  UFPs are those particles measuring less than 0.1 microns in diameter. Poorly sealed or maintained printers can lead to complaints of indoor air quality from UFPs. UFPs are also a component of wood smoke and engine exhaust.
  • Volatile Organic Compounds (VOC’s)
    Volatile organic compounds (VOCs) are emitted as gases from certain solids or liquids. VOCs include a variety of chemicals, some of which may have short- and long-term adverse health effects. Concentrations of many VOCs are consistently higher indoors (up to ten times higher) than outdoors.
  • Other contaminants, depending on site specific needs.  Call our office. We can provide the necessary research for contaminants not listed above, then advise you on availability of test media and personnel. 

Depending on the targeted contaminant, Ellis will partner with CalScience Laboratories, EMSL, LA Testing, Silliker Labs, and other local and national AIHA- and NVLAP-accredited laboratories. 


iaqservices.gifComplaints and health effects which might be related to building environments are sometimes similar to those from colds, flu, stress and allergies. When the reported complaints are nonspecific and diverse, it can initially be difficult to determine if problems are caused by sources or conditions in the building, and what can be done to remedy the complaints. A building investigation is performed in an effort to make these determinations. In some instances, a specific source of contamination or a specific building condition causing the complaints is readily obvious. In the majority of the cases, however, the investigator must consider all the factors that relate to indoor air quality to identify possible contaminants and stressors which could be responsible for the reported complaints and effects. This requires that the inspecting agency must go through a process of identifying and eliminating numerous potential contaminants, sources and other factors in the hope that the true causal factor will eventually be identified. If requires time and patience on the part of both the building owner and it occupants.