SYCTOM 's incinerators, operated by TIRU will soon be fitted out with radioactivity control systems to prevent entrance of radio active waste. Such implementation aims at reducing health risks due to exposition of operators working in incinerators or in sites receiving incineration residues. Radioactive wastes are supposed to be well managed : in the case where the radioactive elements period is short, they have to be stored for a precise time; in all the other cases, a statutory organism dealing with radioactive waste (ANDRA) has to take charge of them. Meanwhile they may arrived in incinerators by mistake. It's difficult to regulate radioactivity control systems for technical reasons: the measured values can be really different from these in the truck because of radiation decreasing; moreover it can't be correlated to an activity, hence it can't be compared to exemption values ot to the limits that characterise a radioactive substance. It can explain why regulated documents don't indicate the way to fix alarm threshold. Implementing such a system is not sufficient: when the alarm sound, the following steps can be applied: checking the missing if interference, potential truck return to sender, putting the truck in quarantine, information of authorities and main actors, calling on a specialize company to locate, extract and package the radiation source, storage of this source and spectrometric analysis to identify and quantify the radioactive elements in order to determinate its way of elimination.