SURFACE INTERVAL CREDIT TABLE. 



REPETITIVE GROUP AT THE END OF THE SURFACE INTERVAL 



INSTRUCTIONS FOR USE 



Surface interval time in the 

 table is in hours and minutes 

 ("7:59" means 7 hours and 59 min- 

 utes). The surface interval most be 

 at least 10 minutes. 



Find the repetitive group designation letter 

 (from the previous dive schedule) on the 

 diagonal slope. E^ter the table horizontally to 

 select the listed surface interval time that is ex- 

 actly or next greater than the actual surface interval 

 time. The repetitive group designatioA for the end of 

 the surface interval is at the head of the vertical dolumn 

 where the selected surface interval time is listed. For ex- 

 ample — a previous dive was to 110 ft. for 30 minutes. The 

 diver remains on the surface 1 hour and 30 minutes and wishes 

 to find the new repetitive group designation: The repetit ive group 

 from the last column of the 110/30 schedule in the Standard Air Decompression Tables is "J". 

 Enter the surface interval credit table along the horizontltl line labeled "J". The 1 hour and 47 

 min. listed surface interval time is next greater than ^e actual 1 hour and 30 minutes surface 

 interval time. Therefore, the diver has lost sufficient inert gas to place him in group "G" (at 

 the head Of the vertical column selected). 



♦NOTE: Dives following surface intervals of more than 12 hours are not considered repetitive 

 dives. Actual bottom times in the Standard Air Decompression Tables may be used in com- 

 puting decompression for such dives. 



(Rev. 1958) 



J.66 



