safe
better safe than sorry: seebetter.
play (or play it) safe (or for safety) take precautions; avoid risks.
safe as houses: seehouse.
a safe bet: seebet.
a safe pair of hands
1 (in a sporting context) used to refer to someone who is reliable when catching a ball.
2 used to denote someone who is capable, reliable, or trustworthy in the management of a situation.
to be on the safe side in order to have a margin of security against risks.
2000Tom ClancyThe Bear and the Dragon To be on the safe side, the messages were super-encrypted with a 256-bit system specially made at the National Security Agency.