Air valve

I tried to use handy air valve and tank for bicycle today.
Hand pump type one can give the pressure about 0.2 MPa. The pressure is too low for road bike's tire. It's be needed from 0.8 to 1.0 MPa. So, I tried air valve and tank.
As a train, I tried it today. As a result, it was easy to reach about 0.6 MPa. It will be enough to ride for some kilometers.
When the CO2 went out from the tank, CO2 change from liquid to gas, and conduct heat away. My finger had damaged by the coldness.