(19)

(11)

EP 0 799 462 A2

(12)

(43) Date of publication: 08.10.1997 Bulletin 1997/41 (21) Application number: 95940396.0 (22) Date of filing: 19.12.1995

(51) International Patent Classification (IPC):  G08B 13/ 22( . ) (86) International application number: PCT/GB1995/002971 (87) International publication number: WO 1996/019783 (27.06.1996 Gazette 1996/29)

(84) Designated Contracting States: BE CH DK ES FR GB GR IE IT LI NL PT SE (30) Priority: 20.12.1994 GB 19940025742 (71) Applicant: SCANTRONIC LIMITED Greenford, Middlesex UB6 7RJ (GB)	(72) Inventor: ARMSTRONG, David Powys SY22 6YE (GB) (74) Representative: Kensett, John Hinton  Saunders & Dolleymore, 9 Rickmansworth Road Watford, Hertfordshire WD1 7HE Watford, Hertfordshire WD1 7HE (GB)