TSO₃ Signs Five New Agreements in the United States

May 5, 2004

Québec City, May 5, 2004 – TSO3 Inc. (“TSO3”) announced today the signing of five additional agreements with referral sites in the United States, including four with major hospitals and one with an industrial customer. These new agreements were negotiated in collaboration with SKYTRON, the distribution partner of TSO3, and are in addition to the those previously announced, bringing the number of technological showcases for the 125L Ozone Sterilizer in the United States to seven.As announced in recent months, the Company’s intention has been to sign on a total of five to 10 agreements with influential U.S. hospitals to act as referral sites.

“We are very happy to announce, as planned, the involvement of these additional hospitals in our program. Referral sites have a strategic role in the marketing of our product and their involvement requires many resources and time,” said Jocelyn Vézina, the CEO at TSO3. “They are well aware of the challenges that a new sterilization process must overcome. By committing to these agreements, they are showing their keen interest in our product and their conviction that our current compatibility program meets their needs.”

As Dave Mehney, CEO of Skytron pointed out, “For several months, our marketing efforts among potential customers for the 125L have confirmed the importance of the demand in the United States. The recent AORN (Association for Registered Nurses) congress in San Diego allowed us to add several dozen names to the list of hospitals interested in the ozone sterilizer. The need for a new low temperature sterilization technology is present more than ever, and the signing of these referral site agreements is proof. We are very enthusiastic about the market launch of the 125L in the United States and we are also very confident about its commercial success.”

Thanks to the numerous contacts made by TSO3 and its partner SKYTRON in recent months, it is not unlikely that the Company will sign further agreements with additional well regarded American hospitals during the year, in order to increase the visibility of its product in the U.S. health network.

The referral site program

The purpose of the referral site program is to allow hospitals that are renowned for their technological advances to use a sterilization method that combines, for the first time in low temperature sterilization history, the advantages of being fast, inexpensive and non-toxic.  At the same time, it allows these hospitals to fulfill their corporate mandate of researching and implementing cutting-edge technology where appropriate.

With this program, SKYTRON & TSO3 plan to demonstrate the significant cost savings of the ozone sterilization technological platform and to reaffirm its many product benefits with satisfied customer referrals.  SKYTRON & TSO3 will also take this opportunity to gather feedback from users that will facilitate the development of new products and accessories, increasing even further the productivity of the 125L.

Seven Canadian hospitals have already entered into the referral site program.

About SKYTRON

SKYTRON, a division of the KMW Group, Inc., is a leading provider of surgical support systems, products and services and technologies to hospitals, surgical centers, healthcare clinics and group purchasing organizations.  The company was established in 1972, quickly becoming the market leading supplier of quality focusable lighting systems in the United States.  SKYTRON has continued its steady growth and product menu of equipment and services, including operating room, emergency and exam lighting, cameras, tables, ceiling-mounted equipment management systems, stainless steel equipment and washer-disinfectors.

To learn more about SKYTRON visit the company’s Web site at: http://www.skytron.us

About TSO3

TSO3 Inc. is located in Québec City, Québec, Canada, and was founded in 1998. TSO3 currently has 45 employees, 17 of whom work exclusively in the Research and Development department. The company’s mission is to develop and market innovative and comprehensive sterilization solutions.

TSO3 has perfected a novel sterilization process using ozone as a sterilizing agent. The first product based on this technological platform is the 125L Ozone Sterilizer, which is intended for hospital sterilization units. The 125L – named after its 125-litre/4.3-cubic-foot capacity – was designed to sterilize the new generation of surgical and diagnostic instruments made of non-heat-resistant materials such as polymers and other plastics. The ozone sterilization process is a safe, efficient, fast and cost-effective response to evolving sterilization needs.

The 125L Ozone Sterilizer was licensed by Health Canada in May 2002 and TSO3 was granted U.S. Food and Drug Administration (FDA) approval September 3, 2003.

The Company’s R&D team has also undertaken the development of a smaller, point-of-use ozone sterilization device for operating rooms and private clinics, and is planning the development of an industrial-sized device for manufacturers of medical instruments, among others.

The statements in this release and oral statements made by representatives of TSO3 relating to matters that are not historical facts (including, without limitation, those regarding the timing or outcome of any financing undertaken by TSO3,are forward-looking statements that involve certain risks, uncertainties and hypotheses, including, but not limited to, general business and economic conditions, the condition of the financial markets, the ability of TSO3 to obtain financing on favourable terms and other risks and uncertainties.

The TSX has neither approved nor disapproved the information contained herein and accepts no responsibility for it.

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