47 Meters Down

At the depth the characters are, experts suggest there would be less than 15 minutes of air for them.

At some point, the instructor on the boat tells the divers that he delayed sending more air tanks because that would increase their risk of narcosis. 47 meters have limited effect on divers (a common saying among divers is "40 meters one drink, 50m two drinks") and the risk of "hallucinations" is largely exaggerated in the case of two young women in good health. Besides, delaying the delivery of additional air tanks drastically increases the risk for the divers to die from lack of air, obviously a far worse scenario than narcosis (you should also consider the risk that the fall might have damaged their equipment and caused abnormal air consumption). A normal reaction should therefore have been to send additional tanks as soon as possible, ideally attached to a cable that can lead the divers back to the boat (instead of just dropping the tanks in the water with a flashing light).

One of the crew members is credited as both a safety diver, and "broccoli wrangler".

Featured in Chris Stuckmann Movie Reviews: 47 Meters Down (2017)