In terms of semiconductor physics, transistor safe operating current range is given in the datasheet. If you take them further, a phenomenon known as thermal runaway will occur. It occurs due to heat up, the internal resistance starts to drop even more allowing more current to flow, before such occur. Normally such transistor are sensed by ptc/ntc to shutdown the system. Before this occurs. You can add safeties like placing safe value resistor to limit the current. place current transformer or use shunt resistor to sense it before its too late. Means you need to make smart circuit which will sense these dangers.