Table 2 makes it possible to determine the value of the degree of nitrogen concentration in tissues (category of residual nitrogen) before a repetitive dive as a function of the time spent on the surface (Surface Interval), as well as the time of complete nitrogen release from the body.
To calculate the nitrogen residual category residual nitrogen before a repetitive dive, you have to select in Table 2 the row that corresponds to the value of residual nitrogen category after your previous dive ..
In this line find the time you spent on the surface and go down in the column. (If the surface time is between the two values indicated in the table, the smaller value is used in the calculation).
In the bottom highlighted line will be the desired category of residual nitrogen before a second dive. For example, if the surface interval is between 20 minutes (Category C) and 40 minutes (Category B), the category selected for a repetitive dive must be Category C.
The total nitrogen release time is located in the penultimate column of the line corresponding to the residual nitrogen category value after your previous dive. In the last column is the required interval time before the upcoming air travel.