The issue and maintenance of the Cospas Sarsat Type Approved Certificate (CSTAC) of each 406 Mhz transmitter model is conditional on the use of original batteries. The Secretariat recommends the exclusive use of batteries supplied by the manufacturer or by recognised service centres so that the transmitter can guarantee the performance required by Document C/S T007 - Standard for the approval of the 406 Mhz Cospas Sarsat transmitter model. It has been ascertained, in fact, that the poor quality of non-original batteries causes activation problems and malfunctions which, in dangerous situations, constitute a serious risk to the safety of human life.