<\/span><\/p>\n[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_2,1_2″ _builder_version=”4.22.0″ _module_preset=”default” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_column type=”1_2″ _builder_version=”4.22.0″ _module_preset=”default” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_image src=”https:\/\/courses.asiascubainstructors.com\/wp-content\/uploads\/2024\/09\/RDP-front.png” alt=”rdp front” title_text=”RDP-front” show_in_lightbox=”on” _builder_version=”4.22.0″ _module_preset=”default” global_colors_info=”{}” theme_builder_area=”post_content”][\/et_pb_image][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.22.0″ _module_preset=”default” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_image src=”https:\/\/courses.asiascubainstructors.com\/wp-content\/uploads\/2024\/09\/rdp-back.png” alt=”rdp back” title_text=”rdp-back” show_in_lightbox=”on” _builder_version=”4.22.0″ _module_preset=”default” global_colors_info=”{}” theme_builder_area=”post_content”][\/et_pb_image][\/et_pb_column][\/et_pb_row][et_pb_row make_equal=”on” _builder_version=”4.22.0″ _module_preset=”default” background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”||||false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” custom_padding=”||||false|false” global_colors_info=”{}” custom_padding__hover=”|||” theme_builder_area=”post_content”][et_pb_text _builder_version=”4.22.0″ _module_preset=”40f87f69-68a0-4a74-8d3a-23f3acd6bdad” global_colors_info=”{}” theme_builder_area=”post_content”]<\/p>\n
RDP Finding your Pressure Group after a dive<\/h3>\n
Find your maximum depth at the top of the RDP table and move down to find your planned bottom time.<\/p>\n
Follow the black arrows to locate the corresponding Pressure Group<\/strong> (letters A-Z) after the dive.<\/p>\nFor example, after a dive to 18 meters for 6 minutes, your Pressure Group is A. After a dive to 18 meters for 36 minutes, your Pressure Group is N.<\/p>\n
Always round to the conservative side. A dive to 18 meters for 37 minutes would put you in Pressure Group O.<\/p>\n
<\/p>\n
No Decompression Limit<\/h3>\n
The black box shows the maximum dive time you can plan at this depth without the need to make a decompression stop (No Decompression Limit<\/strong>). For 18 meters this is 56 minutes (this would put you in Pressure Group W).<\/p>\n <\/p>\n
Finding your Pressure Group after a Surface Interval<\/h3>\n
Follow the arrows to the right and down to find your Pressure Group after a surface interval. Starting in Pressure Group O, and spending 20 minutes (18-23 minutes) on the surface would put you inPressure Group K.<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ make_equal=”on” _builder_version=”4.22.0″ _module_preset=”default” background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”||4px||false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_column type=”3_5″ _builder_version=”4.16″ _module_preset=”default” custom_padding=”||||false|false” global_colors_info=”{}” custom_padding__hover=”|||” theme_builder_area=”post_content”][et_pb_text _builder_version=”4.22.0″ _module_preset=”40f87f69-68a0-4a74-8d3a-23f3acd6bdad” custom_padding=”||5%|” global_colors_info=”{}” theme_builder_area=”post_content”]<\/p>\n
Residual Nitrogen Time<\/h3>\n
After a dive, you have nitrogen in your system. This is shown by your Pressure Group but can also be measured as Residual Nitrogen Time<\/strong> (RNT). The RNT can be found on the back of the RDP. The top number in the white field of each box represents RNT.<\/p>\nFor example, if you are in Pressure Group K, your RNT for 10 meters is 59 minutes. For 14 meters, the RNT would be 40 minutes.<\/p>\n
In other words, when in pressure group K, the amount of nitrogen in your body is what you would accumulate after a dive to 14 meters for 40 minutes.<\/em><\/p>\n[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ _module_preset=”default” custom_padding=”|0px||5%” custom_padding_tablet=”” custom_padding_phone=”10%|||0px” custom_padding_last_edited=”on|phone” global_colors_info=”{}” custom_padding__hover=”|||” theme_builder_area=”post_content”][et_pb_image src=”https:\/\/courses.asiascubainstructors.com\/wp-content\/uploads\/2024\/09\/residual-nitrogen.jpg” alt=”residual nitrogen” title_text=”residual nitrogen” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.22.0″ _module_preset=”default” animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}” theme_builder_area=”post_content”] [\/et_pb_image][\/et_pb_column][\/et_pb_row][et_pb_row make_equal=”on” _builder_version=”4.22.0″ _module_preset=”default” background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”||||false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” custom_padding=”||||false|false” global_colors_info=”{}” custom_padding__hover=”|||” theme_builder_area=”post_content”][et_pb_text _builder_version=”4.22.0″ _module_preset=”40f87f69-68a0-4a74-8d3a-23f3acd6bdad” global_colors_info=”{}” theme_builder_area=”post_content”]<\/p>\n
Total Bottom Time<\/h3>\n
When planning a second dive, you need to consider the nitrogen that is left in your system after the first dive and the surface interval. For instance, we found that the residual nitrogen time for Pressure Group K and 14 meters, is 40 minutes.<\/p>\n
It’s as if you ‘have already spend 40 minutes on 14 meters’. so, to determine your Pressure Group after the second dive you need to add the residual nitrogen time to your Actual Bottom Time<\/strong>.<\/p>\nFor instance, if you are planning a second dive to 14 meters for 45 minutes, the amount of nitrogen accumulated after this dive would be equal to a dive of 40 + 45 minutes, so 85 minutes.<\/p>\n
This is called the Total Bottom Time<\/strong>.<\/p>\n <\/p>\n
Adjusted No Decompression Limit<\/h3>\n
The Adjusted No Decompression Limit<\/strong> (the bottom number in the blue field of the RDP box) is the maximum bottom time for your second dive. For instance for your dive to 14 meters (being in Pressure Group K), the adjusted no decompression time would be 58 minutes.<\/p>\nLooking at the front of the table, we can find that the no decompression limit (maximum dive time) for a dive to 14 meters is 98 minutes. Being in pressure group K is ‘as if’ you have already been diving at this depth for 40 minutes (your residual nitrogen time). So we you are allowed 58 minutes more; 58\u00a0 + 40 = 98.<\/em><\/p>\n <\/p>\n
Planning a repetitive dive<\/h3>\n
Now that you know your theoretical dive time or Total Bottom Time<\/strong> you can find the Pressure Group after your second dive. You can find this on the front of the table. For the second dive to 14 meters, your total bottom time is 85 minutes. (residual nitrogen time 45 minutes + actual bottom time 45 minutes).
This would put you in Pressure Group W.<\/p>\n[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row make_equal=”on” _builder_version=”4.22.0″ _module_preset=”default” background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”||||false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” custom_padding=”||||false|false” global_colors_info=”{}” custom_padding__hover=”|||” theme_builder_area=”post_content”][et_pb_text _builder_version=”4.22.0″ _module_preset=”40f87f69-68a0-4a74-8d3a-23f3acd6bdad” global_colors_info=”{}” theme_builder_area=”post_content”]<\/p>\n
Finding the minimal surface interval<\/h3>\n
After your first dive, check your Pressure Group\u2014let’s say you’re in Pressure Group W.<\/p>\n
Using the Repetitive Dive Timetable (back of the RDP), move to the depth for your second dive, move right and find an Adjusted No Decompression Limit<\/strong> (blue field) that fits your plan. For example, to dive to 12 meters for 60 minutes, you must be in Pressure Group R (not S, as that only allows 59 minutes).<\/p>\nNext, on the Surface Interval Table (front of the RDP), find how long it takes to move from Pressure Group W to R. In this case, 16 to 19 minutes. So, the minimum surface interval is 16 minutes.<\/p>\n
<\/p>\n
Finding the maximum depth<\/h3>\n
Again, after your first dive, check your Pressure Group\u2014let’s say you’re in Pressure Group W and you want to make a 30 minute dive.<\/p>\n
Using the Repetitive Dive Timetable (back of the RDP), move to the column of your Pressure Group and find an Adjusted No Decompression Limit<\/strong> (blue field) that is higher than your planned time. In this case (being W) you could dive to 10 meters for maximum 59 minutes, 12 meters for 31 minutes, and 14 meters for 11 minutes. So, a dive for 30 minutes would be to a maximum depth of 12 meters.<\/p>\n <\/p>\n
Special rules<\/h3>\n
Special rules for dive planning can be found on the back of the table. Some notable rules are:<\/p>\n
Safety stops – When planning a dive that puts you within 3 Pressure Groups of a no decompression limit and for any dive to a depth of 30m or deeper (the grey cells of the table), a safety stop is required.\u00a0<\/strong><\/p>\nOf course it’s always good practice to make a safety stop, but when calculating the minimum time for a series of dives, the safety stop should only be included if required. If not, you can omit it when determining the total dive time.<\/em><\/p>\nFlying after diving – After repetitive dives and\/or multiple days of diving a minimum surface interval of 18 hours (not 24 hours!) <\/em>is suggested before flying.<\/p>\nWXYZ rule – If you are planning 3 or more dives in a day: Beginning with the first dive, if your ending Pressure Group after any dive is W or X<\/strong>, the minimum surface interval between all subsequent dives is 1 hour<\/strong>. If your ending Pressure Group after any dive is Y or Z<\/strong>, the minimum surface interval between all subsequent dives is 3 hours<\/strong>.<\/p>\nNote: the eRDPml will warn you automatically if your pressure group is W, X, Y, or Z. When using the RDP table you need to figure this out by yourself.<\/em><\/p>\n <\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.22.0″ _module_preset=”default” locked=”off” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_column type=”4_4″ _builder_version=”4.22.0″ _module_preset=”default” global_colors_info=”{}” theme_builder_area=”post_content”][et_pb_text _builder_version=”4.22.0″ _module_preset=”default” hover_enabled=”0″ global_colors_info=”{}” theme_builder_area=”post_content” sticky_enabled=”0″]<\/p>\n