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ClearSign Combustion Corporation ClearSign Technologies Corporation Provides Second Quarter 2021 Update SEATTLE , Sept. 8 , 2021 / PRNewswire / -- ClearSign Technologies Corporation ( Nasdaq : CLIR ) ( " ClearSign " or the " Company " ) , an emerging leader in industrial combustion and sensing technologies that improve energy , operational efficiency and safety while dramatically reducing emissions , today provides an update on operations for the second quarter ended on June 30 , 2021 . " This last quarter has been a mix of great progress and encouragement as we move multiple product lines through the technical stages of commercialization and customer engagement , " Jim Deller , Ph.D. , Chief Executive Officer of ClearSign . " Admittedly , the past days have not been without some frustration . What continues to bring me confidence are the developments in the strategic alliances we have made and the technical and commercial maturing of both our major product lines , both of which feed the strengthening of our proposal pipeline , " concluded Dr. Deller . Recent strategic and operational highlights during and subsequent to the second quarter of 2021 include : Advanced process burner performance capabilities to meet or exceed normal refinery requirements : On fuel gas blends ranging from natural gas to blends with 80 % hydrogen content , including in extremely tight multi burner settings , the Company's burners operate over a turn - down range from 100 % of design firing rate down to 20 % . The burners can light off on any fuel in that range , including from a cold start when the furnace is full of fresh air . Depending on heater conditions , ClearSign can make NOx guarantees typically between 5ppm and 9ppm . Performed witness test and shipped process burner to Super Major's refinery in Europe : The burner has been installed and awaits startup which is expected early in the fourth quarter this year . This project will be the first Super Major process burner installation , and the first in Europe . Received , commissioned and held customer demonstrations with a newly fabricated 125hp ClearSign Core fire tube boiler burner : Burner demonstrates sub 2.5ppm NOx . This was the first product demonstration as part of the agreement with California Boiler for the sale and installation of " ClearSign Core enabled ultra - low NOx boiler burners into the U.S. market . The boiler has been deployed in recent days for use at a customer site . 500hp burner designed and delivered to California : Burner is being commissioned and readied for customer demonstrations . TM II Joined the Russell Microcap® Index : The Company was added to the index at the conclusion of the 2021 Russell indexes annual reconstitution which became effective after the US market opened on June 28th . Completed the Performance Testing and Application for Firetube Boiler Burner Certification in China and subsequently received certification : With this certification , the Company can produce , market and sell its 125hp fire tube boiler burners throughout China . Cash , cash equivalents and short term investments were approximately $ 10,600,000 on June 30 , 2021 . There were 31,479,454 shares of our common stock issued and outstanding as of June 30 , 2021 . The Company will be hosting a call at 5:00 PM ET today . Investors interested in participating on the live call can dial 1-866-372-4653 within the U.S. or 1-412-902-4217 from abroad . Investors can also access the call online through a listen - only webcast at https://www.webcaster4.com/Webcast/Page/987/42573 or on the investor relations section of the Company's website at http://ir.clearsign.com/overview . The webcast will be archived on the Company's investor relations website for at least 90 days and a telephonic playback of the conference call will be available by calling 1-877-344-7529 within the U.S. or 1-412-317-0088 from abroad . Conference ID 10159749. The telephonic playback will be available for 7 days after the conference call . About ClearSign Technologies Corporation ClearSign Technologies Corporation designs and develops products and technologies for the purpose of improving key performance characteristics of industrial and commercial systems , including operational performance , energy efficiency , emission reduction , safety and overall cost - effectiveness . Our patented technologies , embedded in established OEM products as ClearSign CoreTM and ClearSign EyeTM and other sensing configurations , enhance the performance of combustion systems and fuel safety systems in a broad