How would you describe the safety features built into the fast breeders?
The fast breeder satisfies all the current safety norms for nuclear reactors. There is a steady state of the nuclear reactor system. There can be transient states. These transient states should not damage the core leading to an accident.
So there are various mechanisms set up to see that the core is not damaged during any such event.
The reactor may be crammed so that power is reduced, controlling the temperature and the neutronics. In addition, in our system there is sodium, which catches fire if it comes into contact with air.
So one should prevent sodium leaks and have large number of sensors to check for leaks. Sodium in contact with moisture produces hydrogen so we need to detect even small amounts of hydrogen and so on.
In short, there are some generic safety measures that prevent the transient to affect the core and then there are specifics, like in our case sodium-related. There are design-based accidents and non-design-based accidents which one needs to take care of.
There are dumps to remove sodium?
They are there in critical systems. We do not like to totally shut down the reactor system, as sodium solidifies on cooling and then it becomes a problem to restart the system. So certain heaters are installed.
You have gravity-based systems?
The dumping systems are gravity-based systems, thus even if there is total power failure etc as it happened in Fukushima nuclear plant (in Japan after the recent tsunami), we will have safety.