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One of the greatest concerns of today’s facility managers is the health and safety of the occupants of their building. Indoor Air Quality is a key factor. Technology now exists to allow continuous monitoring to help control the air quality of a facility. Air quality sensors can be placed in individual rooms and in air ducts and can send data directly to the building management system. This type of “on-line” monitoring system offers a number of important benefits:

Improved comfort means increased productivity.
People do not perform well on the job when they are uncomfortable. Excess noise, unpleasant smells, hot or cold temperatures or poor air quality—all of these disturbances affect a person’s ability to concentrate. In some cases the severity of these factors can actually create headaches, nausea and other conditions that further reduce job performance and further impact a company’s bottom line. Independent studies by ASHRAE (American Society of Heating, Refrigeration and Air-Conditioning Engineers, Inc.), BOMA (Building Owners and Managers Association), and other industry specialists have shown that proper environmental conditions have a direct and quantifiable impact on the bottom line. These studies also show that the productivity losses due to poor comfort can dwarf the costs of adding an On-line Air Quality Monitoring System.

Potential problems can be identified early before they reach a critical stage.
Information from Air Quality Sensors can be recorded over time and easily imported into standard spreadsheet packages for analysis. This data helps the facility manager identify and correct any potential Air Quality problems in the early stages. Some of the potential problems which can be identified by this type of system include:
• Could poorly located intakes actually be introducing poor quality air into the facility?
• Are the components of the facility (such as carpets, finishes, furnishings or equipment) creating air quality problems?
• Are there chemical contaminants located within the building?

Energy savings through demand-based control of outside air intake.
With Air Quality Monitoring as a component of the building management system, outside air intake rates can be adjusted in direct relation to actual air quality needs. The benefits of this “demand-based” control are two-fold: It insures that air quality needs within the facility are met and it eliminates the supply of excess outside air, reducing energy usage. With Air Quality Monitoring and optimized control of outside air intake, an 80,000 sq. foot office building can save over $2,000 per year in energy bills. The specific details and calculations for this example can be found on the PDF Datasheet on Air Quality Monitoring.

A proactive approach demonstrates your concern for your tenants.
Air Quality Monitoring assures existing and potential tenants about the quality of your facility and your commitment to tenant satisfaction. Polls show that indoor air quality is one of the most important factors considered by building occupants and potential tenants.

Total Contaminant Sensing
versus Carbon Dioxide Sensing

There are two basic methods of On-line Air Quality Monitoring: CO2 (Carbon Dioxide) Sensing and Total Contaminants Sensing.

CO2 Sensing
CO2 is one of the primary by-products of people occupying an enclosed space. It is also easily eliminated by proper ventilation with outside air. CO2 is often used as an indicator of air quality and ASHRAE recommends that CO2 levels not exceed 1,000 ppm inside a space. The weakness in the use of CO2 as an indicator, however, is that CO2 levels below 1,000 ppm do not guarantee that air quality is good. All kinds of contaminant gases could still be present. This problem led to the creation of a Total Contaminant Sensor.

Total Contaminant Sensing
Total Contaminant Sensors detect a wide variety of contaminants that are typically found in indoor environments including CO2. This type of sensor provides a much more accurate representation of actual air quality than a CO2 Sensor. Some of the contaminants detected by a Total Contaminants Sensor include Volatile Organic Compounds (VOCs) emitted by detergents, paints, cleaners, new carpet, air fresheners, disinfectants, carpet and tile adhesives, solvents and tobacco smoke, and other gases such as CO2, ammonia, chlorine carbon monoxide, methane formaldehyde.

Total Contaminant Sensing —
A Powerful & Economic Tool

Dozens of different “gas specific” sensors located throughout a building would be the most accurate way to monitor and control air quality conditions within a building. However, this would be extremely expensive and “overkill” for the vast majority of facilities. A powerful and yet economical alternative is a Total Contaminant Sensor. It eliminates the need for dozens of “gas specific” sensors by combining them all into one sensor. The signal from the sensor doesn’t directly correspond to the ppm level of any one contaminant, but to the combined level of many contaminants. This information can be recorded over time and easily imported into standard spreadsheet packages for analysis. The information can then be correlated with specific conditions in the facility to not only maximize air quality, but to identify and correct any potential air quality problems.
For example, what signal is seen when the facility is unoccupied and maximum outside air is being brought in? This signal is probably a good indicator of the optimum air quality achievable for the facility. Conversely, the signal level seen when the facility is fully occupied and at minimum (or zero) outside air may be a good indicator of the worst air quality conditions that the facility will experience. Building processes can then be adjusted to try to maintain the optimum air quality. The facility manager can also look for “spikes” in the sensor readings in specific rooms or at specific times of the day and corrolate these spikes with equipment, furnishings or tasks such as cleaning. The facility manager can then identify and correct the cause of the spike (a chemical contaminant located within the building for instance) or adjust building operations to compensate for naturally-occuring contaminants such as those from carpeting, laminates or cleaning supplies.
Total Contaminate Sensing is therefore an excellent troubleshooting tool because potential problems can be identified early and corrected before they reach a critical stage.

Printable PDF datasheet on the benefits of Air Quality Monitoring