 The name is an acronym standing for Tone Ring Illuminator Model, referring to the then innovative electronic ringer ("warbling", as opposed to the traditional bell) and the illuminated dial.The luminous dial or betalight contained the mildly radioactive element tritium, which later caused some concern about safety.In June 1991 the United Kingdom Atomic Energy Authority at Harwell was fined £3,000 by Wantage Magistrates Court for accumulating radioactive waste, having collected several thousand Trimphone luminous dials in a skip.