GB 12951-1996 specifies the technical conditions for americium-241α radioactive sources for ion-sensing smoke fire detectors. The standard specifies the nuclear physical parameters such as activity, specific activity, and half-life of radioactive sources, and also requires their sealing performance, structural design, and environment performance. It also covers the production of radioactive sources, inspection procedures, and quality control specifications. The standard ensures that americium-241α radioactive sources play a safe, stable, and accurate role in ion-sensing smoke fire detectors, ensuring the sensitive monitoring of fire smoke by detectors, providing key support for the Reliability of fire warning systems, and safeguarding life and property safety.