You should do a thorough check of your electric garage door, even if it appears to work every day without a problem. A couple of minutes is all it takes to check that your garage door's sensors work correctly and don't pose a danger to children or pets.
Assuming your garage door is not too old, it should have "photo eyes" that detect obstacles. Check that these are mounted no more than six inches off the ground, and then test them by placing an object such as a box in their sights. If everything is working as it should, you should not be able to close the door while the obstacle is in place.
For the final test, lie an object less than 15cm tall -- such as a plank of wood -- at the bottom of the door. Close the garage door with its remote. When the bottom of the door touches the wood (which could be a child's foot), it should automatically re-open.
If your door fails any of these tests, it's time to call out the experts to get it fixed.
How To Do a Garage Door Safety Test Video [LiftMaster]