Tag Archives: Indoor air quality

Indoor Air Quality (IAQ) Testing Services (including chemicals / carcinogens like Formaldehyde) Available – Fast Onsite Results!

Formaldehyde NFPA Diamond from MSDS (Material Safety Data Sheet)

Formaldehyde NFPA Diamond from MSDS (Material Safety Data Sheet)

ScanTech Technical Consulting performs indoor air quality tests including particulate matter in the air (residential and commercial) in the 0.5 – 2.5 micron and 2.5 micron + range  (PM 2.5 and PM10) in order to evaluate how clean your air is with respect to dust and other fine particles. We also offer formaldehyde and VOC levels testing due to chemicals used in the manufacture of pressed wood flooring, lumber, laminates, glues and other adhesives in your home and factory/office.

More information on formaldehyde can be found here:

http://emfsurveydallas.com/formaldehyde-indoor-air-pollutant-and-testing/

We can also test for VOCs, (Volatile Organic Compounds) CO2 (Carbon Dioxide) levels and O2 oxygen levels in your home to check ventilation quality. Datalogging over time available to show trends and measure the effects of HEPA filtration and electrostatic air ionization units.

Our background in organic and environmental chemistry, epidemiology, advanced microbiology, medical geology  and human physiology makes us uniquely qualified to answer your concerns regarding the invisible environment you breathe every day.

July 2016 ruling by the EPA on the emissions of formaldehyde of wood products produced or imported into the United States:

https://www.epa.gov/formaldehyde/formaldehyde-emission-standards-composite-wood-products-0#additional-resources

The following tables and information are from:

Health Effects Notebook for Hazardous Air Pollutants

To convert concentrations in air (at 25°C) from ppm to mg/m3: mg/m3 = (ppm) × (molecular weight of the compound)/(24.45) For formaldehyde which is CH20: 1 ppm = 1.23 mg/m3.

Explanation of Formaldehyde Levels

Formaldehyde Regulatory and Health Levels Comparison

Formaldehyde Regulatory & Health Levels Comparison

AIHA ERPG–American Industrial Hygiene Association’s emergency response planning guidelines. ERPG 1 is the maximum airborne concentration below which it is believed nearly all individuals could be exposed up to one hour without experiencing other than mild transient adverse health effects or perceiving a clearly defined objectionable odor; ERPG 2 is the maximum airborne concentration below which it is believed nearly all individuals could be exposed up to one hour without experiencing or developing irreversible or other serious health effects that could impair their abilities to take protective action.

ACGIH STEL–American Conference of Governmental and Industrial Hygienists’ short-term exposure limit expressed as a time-weighted average exposure; the concentration of a substance which should not be exceeded at any time during a workday.

LC50 (Lethal Concentration50)–A calculated concentration of a chemical in air to which exposure for a specific length of time is expected to cause death in 50% of a defined experimental animal population.

NIOSH IDLH–National Institute of Occupational Safety and Health’s immediately dangerous to life or health limit; NIOSH recommended exposure limit to ensure that a worker can escape from an exposure condition that is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from the environment.

NIOSH REL–NIOSH’s recommended exposure limit; NIOSH recommended exposure limit for an 8- or 10-h time-weighted average exposure and/or ceiling.

OSHA PEL–Occupational Safety and Health Administration’s permissible exposure limit expressed as a time-weighted average; the concentration of a substance to which most workers can be exposed without adverse effect averaged over a normal 8-h workday or a 40-h workweek.

 

MERV (Minimum Efficiency Reporting Value) Ratings and Filters

You generally cannot place a True HEPA filter in your air furnace because of the flow restriction would place too heavy a load on the blower unit. But you can get a higher efficiency MERV filter that can give some of the benefits of better filtration and indoor air quality without unnecessarily straining the HVAC unit or restricting the air flow.

But to get a good balance between clean air and not damaging your HVAC unit, consult with an air conditioning professional and / or consult with the manufacturer regarding the recommended MERV filter range that can be used in your particular model. Also, the higher your MERV rating, the more often you may have to check and/or change it as it will tend to clog faster.

MERV ratings are numbers that generally measure the quality of an air filter, but can be hard to understand without some context and this chart is a handy reference.

 

MERV Chart Air Quality

MERV Rating Chart with application comparisons   *Note – the pm size designations listed should be in um or microns

Allergens Air Purifiers

Air Purifier Guide to Size Ranges of Allergens in microns (millionth of a meter or um)

The MERV rating is a filter standard established by ASHRAE  (American Society of Heating, Refrigerating and Air-Conditioning Engineers) but when you shop for a filter online, you may also find references to MPR and FPR.

MPR (Micro-Particle Performance Rating) is a standard used by 3M (notably the Filtrete series) that rates filter performance with respect to the ability to screen out sub-micron (less than 1 um) particles, but can be confusing when comparing to MERV. Note that less than a micron is on the low end of the PM2.5 Fine particle range as designated by the EPA. (0.5 – 2.5 microns)

FPR (Filter Performance Rating) works a little like MERV numbers (but on a 4 – 10 color coded scale) developed by Home Depot for filters they sell including Honeywell.

To get a relatively close comparison, the following chart may be useful when shopping for a more suitable HVAC filter.

MERV MPR FPR Ratings Compared and Explained from www.airfiltersdelivered.com

MERV MPR FPR Ratings Compared and Explained from www.airfiltersdelivered.com (not endorsed by ScanTech)

While this chart is useful, it is not guaranteed to completely stop all of the biological and inorganic contaminants that are listed. Your mileage may vary.

MERV Filter Models

 

Control of Formaldehyde (HCHO) and VOCs in Indoor Air Quality

One of the first issues to address for pre-existing construction is proper selection of materials that have low VOCs and formaldehyde content (UF or Urea-Formaldehyde) and/or that outgas (release the noxious vapors) relatively quickly. Low emission products include:

  • Low VOC paints
  • Low VOC carpeting (though carpets tend to have inherent issues with collecting/releasing dust)
  • Other mastic (waterproofing putty) products that have low levels of 4-phenylcyclohexane (4-PC) which produces a characteristic odor
  • Pressed wood products that have low formaldehyde (HCHO) levels
  • Formaldehyde-free varnishes and lacquers
  • Softwood plywood
  • Oriented-Strand board
  • Decorative gypsum board
  • Hardwood panels
  • Pressed woods with PF (Phenol-Formaldehyde) resin release less HCHO than UF resins

You might want to AVOID:

  • Medium-Density Fiberboard (MDF) sometimes used in cabinets, furniture and doors
  • Hardwood plywood paneling
  • Particleboard
  • Pressed wood products with UF
  • UF-based Acid Cured Finishes
  • Homes insulated with UFFI (Urea-Formaldehyde Foam Insulation) though this is unlikely to be an issue
  • High humidity (keep between 40 – 50 % RH)
  • Occupying the home or property until a proper out gassing period has passed – preferably during hotter weather
Formaldehyde Emissions from variou Construction Materials

Formaldehyde Emissions from various Construction Materials

Then having an outgas period before occupation is good when possible. Preferably during hot, humid weather which tends to accelerate the exit of gaseous residues from the building materials. If you have an existing wood material that is emitting formaldehyde, then the can be treated with scavenging coatings or encapsulated with vinyl materials.

ASHRAE Ventilation Guidelines 2013

ASHRAE Ventilation Guidelines for Acceptable Air Quality – 2013

Another critical factor is having adequate ventilation, particularly during the initial outgas period. Many homes and multifamily dwellings are often built rather “tight” as a response to the desire for energy conservation and reducing moisture intrusion. If it is not a security issue, keeping the windows open even a crack on opposite sides to create a flowing cross-draft can assist out-gassing as well as opening chimney dampeners.

Factors in formaldehyde levels:

  1. Composition of building materials (formaldehyde potency in manufacture)
  2. Loading factor (amount of material in exposed surface area and volume)
  3. Material age
  4. Adequate ventilation taking into account occupancy and room size
  5. Environmental conditions
Indoor Air Exchange Rate Per Hour Table

Indoor Air Exchange Rate Per Hour Table

 

Formaldehyde Levels Indoor Air Quality

How Formaldehyde Levels Decrease Over Time

The use of sorbents (gas absorbent materials) such as activated charcoal can be used to remove relatively high molecular weight VOCs such as toluene, benzene, xylene and methyl chloroform.

For lower molecular weight (MW) materials such as formaldehyde (HCHO), ethylene, and acetaldehyde then potassium permanganate, (KMnO4) activated alumina or specially impregnated charcoal are better choices than regular activated charcoal.

Other special air cleaners may also be used – consult ScanTech for further information.