Asia Pac Allergy.  2014 Apr;4(2):113-118. 10.5415/apallergy.2014.4.2.113.

Efficacy of the Precise Climate Controller on the reduction of indoor microorganisms

• Moungthong G
• Klamkam P
• Mahakit P
• Chalermwatanachai T
• Thunyaharn S
• Monyakul V

• KMID: 2397114
• DOI: http://doi.org/10.5415/apallergy.2014.4.2.113

Abstract

BACKGROUND
Nowadays, there are many methods to reduce microorganisms in the air, such as dehumidifier, air purifier or humidity and temperature controller. The Precise Climate Controller is an instrument for controlling humidity and temperature, a concept that is demonstrated.
OBJECTIVE
To determine the efficacy of this device, in order to reduce the quantity of the fungi and bacteria in the closed system.
METHODS
This study is a perspective experimental study and is conducted as follows - the air sample in the closed system, a 42-cubic-meter room, is collected before the installation of the Precise Climate Controller. Next, the room is fumed with Aspergillus flavus and closed for 2 days. Then the instrument is in use in order to keep the relative humidity (RH) and the temperature constant at 55% RH and 25 degrees Celsius (℃). The air samples are collected every 3 days for 5 times during the period of 15 days to identify the type and calculate the quantity of the microorganisms.
RESULTS
Before the Precise Climate Controller has been installed. Three species of bacteria are found in the air samples, but none of the fungus exists in the testing room. Once the room has been fumed with a large amount of A. flavus and the instrument is in use for 3 days, nine colonies of A. flavus are identified, but later on when the instrument is in use for 6, 9, 12, and 15 days, the air samples contain neither fungus nor bacteria.
CONCLUSION
After keeping the RH and temperature of the closed system constant at 55% RH and 25℃ by using the Precise Climate Controller, it is found that the efficaciousness in controlling the quantity and species of fungi and bacteria is clinically significant.

Keyword

Climate control; Humidity; Fungal count

MeSH Terms

Air Conditioning*
Air Filters
Aspergillus flavus
Bacteria
Climate*
Colony Count, Microbial
Fungi
Humidity

Figure

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  Fig. 1 The Precise Climate Controller invented by Dr. Veerapon Monyakul, King Mongkut's University of Technology Thonburi.

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  Fig. 2 Diagram comparing the conventional air conditioning system (A) and the Precise Climate Controller system (B). DSP, digital signal processor.

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  Fig. 3 The mean number of organisms inside the testing room before the Precise Climate Controller Installation. CFU, colony-forming unit.

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  Fig. 4 The number of fungal colonies inside the controlled room with relative humidity 55% and temperature 25℃. A. flavus, Aspergillus flavus; CFU, colony-forming unit.

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