Spacecraft --- Space Station --- Escape

If an astronaut has a serious injury, he or she needs to get back to the Earth as soon as possible.
In case of some life-threatening damage to the station (e.g. a serioous fire), the whole crew member of the space station must evacuate.
A Soyuz capsule will always be docked at the ISS, capable of carrying two to three people in emergencies. A crew will take a new Soyuz capsule to the station every six months.

NASA is designing and building a crew-return vehicle (CRV) called X-38, which weigh about 9,000 kg, for emergency use. The X-38 will be able to transport seven people to the surface.
Like the space shuttle, when X-38 re-enters the atmosphere, it will be protected from the heat by ceramic tiles. Once through the atmosphere, the X-38 will glide towards its landing site, use its parachute to slow down and steer, and touchdown on its skid.

Structure of the ISS Propulsion Communication Navigation Power Computer Resupply Escape Research in the ISS