What is the most important tool for safe nitrox diving?

The most important tool for safe nitrox diving is a reliable and accurate dive computer. A dive computer is essential because it continuously tracks the diver's depth and time underwater, and it calculates no-decompression limits based on the specific gas mix being used. Given that nitrox has higher oxygen content than regular air, it introduces unique considerations for oxygen exposure and potential toxicity. A dive computer enables divers to monitor these factors in real time, providing necessary warnings if limits are approached. This capability is crucial for ensuring the diver remains within safe limits for both nitrogen and oxygen, thereby reducing the risk of decompression sickness and oxygen toxicity.

While buddy checks, dive tables, and GPS systems play roles in dive safety, they do not provide the immediate, real-time data and calculations that a dive computer offers, making it the most critical tool in this context.