For how long should a diver stay at 5 metres before ascending to the surface after exceeding bottom time?

When a diver exceeds the recommended bottom time, it's essential to perform a safety stop during ascent to minimize the risk of decompression sickness. In this context, a safety stop typically involves ascending to a depth of about 5 meters (15 feet) for a duration that allows for the body to off-gas nitrogen accumulated during the dive.

The recommended duration for a safety stop at this depth is commonly around 3 to 5 minutes. However, staying longer at 5 meters can provide even more benefit by allowing extra time for the body to eliminate any absorbed nitrogen safely.

Thus, an 8-minute safety stop strikes a balance between ensuring safety and adhering to recommended practices, as it gives the body additional time to reduce inert gas levels. This adjustment is particularly useful if the diver's bottom time exceeded typical limits, enhancing the safety margin during the ascent. Therefore, the answer of 8 minutes at 5 meters is supported by diving safety guidelines that emphasize the importance of gradual ascent and sufficient decompression time after extended dives.