Ice must be at least 4 inches thick for you to be able to walk on it. However even at 4 inches thick it could still be weak enough for you to fall through. Falling through ice means that you will be immersed in extremely cold temperatures.
This video will show you what to do if you fall through a sheet of ice into a cold body of water. Follow these instructions to avoid hypothermia. It could mean the difference between life and death.
This is part of the outdoor survival series. Click the links to the other videos in the section to find more interesting topics about outdoors and surviving the elements.