Grant of Patent

Tristel PLC
04 July 2005


                                  TRISTEL PLC


                                Grant of Patent


Tristel plc ('Tristel' or the 'Company'), the AIM listed supplier of liquid
chemical sterilising solutions to UK hospitals, announces that it has been
granted a patent for the Tristel Sterilising Wipes, the world's first rapid
action sporicidal wipe.

Tristel markets a proprietary chlorine dioxide chemistry that is highly
effective in destroying all types of bacteria (including bacterial spores,
tuberculosis and MRSA), fungi and viruses and is one of a small group of
sporicidal agents that is safe and easy to use.

The Wipe incorporates Tristel's patented chlorine dioxide chemistry. It can kill
all organisms on a pre-cleaned surface with a contact time of only 30 seconds.
This means that medical instruments, such as ENT (Ear Nose & Throat) scopes and
ultrasound transducers, that cannot be immersed in liquid disinfectants, and
cannot be sterilised by heat, can now be decontaminated easily, quickly and
safely.

The Tristel Wipe system generates chlorine dioxide, a well documented, highly
effective and safe biocide, by applying foam to the surface of the wipe which is
rapidly effective against all micro-organisms, including spores. The Tristel
Sterilising Wipe is suitable for use in hospitals, laboratories, GP practices,
dental practices and veterinary clinics. The Tristel Sterilising Wipe is far
superior biocidally to a wipe that uses alcohol or any other available
chemistry.

Tristel plc floated on AIM on 1 June 2005. Teather & Greenwood, Nominated
Advisor and Broker to Tristel, successfully raised £2.0m before expenses by way
of an institutional placing

Tristel's core product range of instrument disinfectants has become the market
leader in the UK Acute & Private Hospital sector. They are used to decontaminate
heat sensitive endoscopic and ultrasound instruments in over 375 hospitals,
representing some 60 per cent of all UK NHS Acute & Private Hospitals.



Contacts:

Tristel plc                                                   Binns & Co PR Ltd
Paul Swinney                 Paul Barnes FCCA                 Paul McManus
Chief Executive              Finance Director                 Tel: [phone]
Tel: [phone]           Tel: [phone]               Mob: [phone]


About the Company

In 1998, the business that became Tristel acquired all world-wide rights to the
patented chemistry. The principal operating subsidiary of the Group was
established at this time to exploit the UK market. Tristel's products include
Instrument Solutions (primarily for flexible endoscopes), Instrument Wipes,
Surface, Water and Skin Disinfectants.

Tristel, based near Newmarket, Cambridgeshire, reported a pre-tax profit of
£0.165m from a turnover of £2.18m for the year ended 30 June 2004.


                      This information is provided by RNS
            The company news service from the London Stock Exchange