ERDPml Quiz 1 Questions and video explanations.

Question 1

After a dive you are in pressure group F. If you then do a 20 min surface interval, what would your ANDL for a dive to 60ft be?


Question 2

You have just completed a dive which put you in pressure group ‘R’. If you complete a 45 minute surface interval, how deep could you go if you now want to do a second dive of 50 minutes?


Question 3

When diving to a depth of 60ft in cold water your NDL for the dive is? 


Question 4

You complete a dive and a surface interval of 49 minutes, this puts you in pressure group ‘J’. What would your ANDL be if you wanted to do a dive to 43ft?


Question 5

If you complete a dive that leaves you in pressure group ‘S’. How long a surface interval would you have to take, if you want to do a second dive to 50 ft for 50 mins?

Question 6

How long will it take in total from the start of the first dive to the end of the last dive to complete the following series of dives. 90 ft for 15 min followed by 40 ft for 120 min followed by 40 ft for 100 min. Including required safety stop time?


Question 7

You are doing a multilevel dive. The first level you want to dive to is 130 ft. What is the next deepest level you can do after this according the ERDPml?


Question 8

The RDP allows ______ repetitive dives than the navy tables?

*a. Longer (Correct Answer)

b. Shorter

c. The Same

d. Decompression

The navy tables have a surface interval credit of 120 mins. The RDP has a surface interval credit of 60 mins.  What this means is that the RDP calculates that the nitrogen leaves your body twice as fast as the navy tables do. This means the RDP will always assume you have less residual nitrogen in your body at the beginning of a subsequent dive than the navy tables. Therefore the RDP will generally give you longer NDLs than the navy tables for repetitive dives. The two models also use different M-values so this is not always true, but it is in most cases.

Question 9

The RDP has ______ compartments and a surface interval credit of ________ minutes

a. 12/60

*b. 14/60 (correct answer) 

c. 12/120

d. 14/120

This is just a fact you need to learn. The RDP is a model based on 14 theoretical tissue compartments that absorb nitrogen at different rates. It assumes that nitrogen is released during a surface interval and just one speed, 60 Minutes. It assumes the nitrogen in your body will half every 60 minutes until you are back in equilibrium. 

Question 10

You are planning a 3 level multilevel dive. The three levels are, 110 ft, 70 ft and 30 ft. You want to spend as long as RDP rules allow at each level. How long will you be underwater including safety stop time if required?