If a delay occurs at the first "D" stop deeper than 50', how should it be handled?

When a delay occurs at the first "D" stop deeper than 50 feet, the appropriate action is to round up the delay and add it to the bottom time. This approach is based on the need to ensure that the diver's safe ascent profile is maintained and that all required decompression stops are adhered to.

In deeper stops, such as those beyond 50 feet, the effects of pressure on the body's tissues become more significant regarding the absorption of nitrogen during the dive. Any delay experienced at this stage can potentially extend the decompression obligation because the longer a diver remains under pressure, the more nitrogen is absorbed, which increases the risk of decompression sickness if ascent protocols are not adjusted accordingly.

By adding the delay to the bottom time, the supervisor ensures that the diver maintains adequate time at shallower stops to allow for proper off-gassing of nitrogen. This practice helps to mitigate the risks associated with ascending too rapidly or without adequate stops. It is crucial to continue monitoring the diver's time and physiological response to ensure safety throughout the ascent.