NAUI Recreational EAN 36 No - Deco Tables High Altitude Tables
Manufacturer Part Number 35517
Two-sided tables - front side contains the table, the back side contains an index outling the terms and definitions. Contains three depth choices, from Sea Level all the way to 10,000 feet.
Dive Table Overview
The NAUI Dive Tables use a Letter Group designation to express the amount of residual nitrogen in your body. The letters range in sequence from A to L. The letter A represents a small amount of nitrogen and the amount of nitrogen increases as the letters progress towards L. When you dive, a Letter Group from the tables designates the amount of nitrogen you have absorbed during the dive. As you spend time on the surface between dives, you are assigned to “lower” Letter Groups as you offgas nitrogen.
When you start a dive again to a given depth, your Letter Group at that time determines the time representing the residual nitrogen in your body. The tables show you how to subtract this time from the normal dive time limits, which results in a shorter time limit for your repetitive dive. You must add your residual nitrogen time to the time you actually spent diving to determine your total nitrogen time at the end of the dive. You use the total time to determine a new end-of-dive Letter Group. The NAUI dive time calculator is based on the NAUI dive tables, but it eliminates the calculations required to determine Letter Groups when you make more than one dive. The dive time calculator also reduces the errors that are often made when reading dive tables. It is easy to learn how to use a dive time calculator, but you should do this only after you are familiar with the procedures for planning dive time limits using the dive tables. A dive time calculator might not always be available, but dive tables usually are (figure 5-4).
A variety of dive tables, dive time calculators, and dive computers exist. The information they provide varies and some are more conservative than others. Numbers and Letter Groups are not always interchangeable between tables. Always use the type of table, calculator, or computer with which you are familiar. If your dive buddy is using a different type, you should agree to use the most conservative dive planning information.