It is not uncommon for powerlifters to tear a biceps tendon (usually the “under hand” with a mixed grip). Pulling with your arms may leave the biceps tendon vulnerable at maximal loads. Be sure to stretch up through all slack in your arms when pulling big loads off the floor.
The front/back lever
Spending time on the gymnastics rings is fun and useful training, and loading your joints heavily isn’t just exclusive to lifting weights. Levers and even variations of movements like the iron cross can be suspect for vulnerable biceps.
The tire flip
I personally fell victim to a tear when I was flipping a 1,000-pound tire, and it can happen at lighter weights, as well. Though the tire flip is useful and a seemingly raw movement, there are points of performance that should be respected. You can protect the biceps while flipping tires by keeping your shoulders and hands as two points of contact. Without definitive shoulder contact, the tire turns into a biceps curl, and at 1,000 pounds, there’s no such thing. Connect with the shoulders to keep your biceps safe.
Atlas stone work
The size and shape of Atlas stones can illicit some poor positions that leave the biceps vulnerable. Pulling the stone with bent elbows off the floor and loading/shouldering the stone with your arms under the stone in the lap position can be biceps suicide. Keep your arms straight off the floor and over the top of the stone (recruiting the lats) when coming out of the lap position.