Electronic Sensor Technology showcases the Air Guardian at two Conferences.

NEWBURY PARK, Calif.--(BUSINESS WIRE)—September 21, 2007 (OTCBB: ESNR - News), EST announced its participation at the American Society for Industrial Security International (ASIS) Conference on September 24, 25, 26 held in Las Vegas, NV and at the Indoor Air Quality Association (IAQA) Annual Meeting and Exposition on October 14, 15, 16 held in Las Vega, NV.

During the ASIS conference and at the Indoor Air Quality Association Exposition, EST will demonstrate its newest product: the Air Guardian at their booth number 882. The Air Guardian provides vapor detection to sense explosive, narcotic, and toxic chemicals and refreshes the air using filters and ion generation.

More information on the company and on the use of the zNose® click on the following link:

http://www.estcal.com/

About Electronic Sensor Technology:

Founded in 1995, Electronic Sensor Technology has developed and patented an Ultra-Fast Chemical Vapor Analyzer.

SEC Filings and Forward-Looking Statements

This press release includes forward looking statements, including the Company's expectations regarding its ability to develop and access capital markets and its ability to achieve expected results in the chemical detection and analysis industry. The forward looking statements are identified through use of the words "potential," "anticipate," "expect," "planned" and other words of similar meaning. These forward-looking statements may be affected by the risks and uncertainties inherent in the chemical detection and analysis industry and in the Company's business. The Company cautions readers that certain important factors may have affected and could in the future affect the Company's beliefs and expectations and could cause the actual results to differ materially from those expressed in any forward-looking statement made by or on behalf of the Company. For a discussion of these factors, please refer to our recent filings with the Securities and Exchange Commission, including our most recent report on form 10-KSB. The Company undertakes no obligation to update forward-looking statements to reflect events or circumstances after the date hereof.

For Further Information:
Contact:

Electronic Sensor Technology
Frank Zuhde, 805-480-1994, ext. 135