Building Management System

With CO2 measuring it is possible to control individual fans, dampers, valves, etc., which create a better indoor environment and energy savings. A common  application is controlling ventilation in rooms with varying numbers of people such as offices, classrooms, and cinemas. The ventilation control is based on temperature and CO2.

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Why measure CO2 for commercial ventilation?
The primary indoor source of CO2 in office buildings is the breathing of the building occupants. CO2 concentration in office buildings typically ranges from 390 to 2500 ppm. Today there are laws about measuring the CO and the maximum allowed value is 35 ppm. Rules about measuring the CO2 do not exist even if it's equally as important. It is therefore useful to measure both gases to ensure personal safety. The Threshold Limit Value for 8-hour timeweighted-average exposures to CO2 is 5 000 ppm. The current American Society of Heating, Refrigeration, and  Air-conditioning Engineers (ASHRAE) recommended minimum ventilation rate for offices is 10 L/s per person, corresponding to an approximate steady state indoor concentration of 910 ppm,  based on the assumptions that outdoor CO2 is 390 ppm and indoor CO2 generation rate is 0.31 L/minperson. Sick Building Syndrome (SBS) is used to describe a set of symptoms with  unidentified etiology frequently reported by workers in office buildings. The individuals who suffer from SBS report that the symptoms occur when they spend time indoors, particularly in office buildings and that the symptoms lessen while away from the building. [1]

How does it work?
In order to have optimum ventilation it is important to use an affordable and stable sensor technology to measure CO2 concentrations to determine the correct level of fresh air in a zone. Proper  CO2 measurements in a space make it possible to control the level depending on the person's air circulation at any given moment. The sensor controls the need of fresh air in individual spaces  and then sends a signal to a computer that controls the main ventilation system. Complete air-handling and air-conditioning units help us create a better indoor environment as well as obviuos energy savings.

Benefits?
- Public safety
- Energy saving
- Reduced costs
- Environmental savings
- Good indoor air quality

 

[1] http://senseair.se/wp-content/uploads/2011/05/6.pdf2013-02-26