The alarm on a radioactive detector gate was tripped (threshold: 1,500 shocks/sec) when a lorry transporting a radium fountain in its load left a recyclable metal waste recovery facility. The operator insulated the radioactive object and notified the fire department. First responders evaluated the risks using a radiameter; given that the primarily alpha radiation emitted could not be detected beyond 10 cm, a 50-cm safety zone was set up. The fountain was wrapped in a polyane film and isolated in a locked hangar. No contamination was recorded on either the lorry driver or personnel likely to be in contact with the fountain. The on-site presence of this radioactive object could not be justified, since the gate was not activated at the time of delivery. Inspection Authorities explained this anomaly by the fact that the fountain had been tucked away in the load. During this incident however, it appeared that site staff were unfamiliar with the protocol to follow (running measurement acquisition software, interpreting results, etc.); consequently, inspectors proposed that the Prefect issue an additional order for the operator to revamp site organisation in the aim of improving responses to such incidents.