Baltic Deco Planner Frequently Asked Question

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Feedback

I'd like to report a problem, how and where ?

You're welcome to file a ticket (you can now do this without registering first), post in the Q&A forum (requires registration) or via  email. If the report is related to a generated dive plan, please be sure to include the plan parameters and if possible, the plan itself. You can use the apps email feature to email the plan to yourself.

I'd like to suggest a feature/enhancement, how and where ?

Please post these in the REEFS forum first. This will give me some time to think about it and let other people chime in. If the feature isn't already on the roadmap, a ticket can be filed to keep it on the map.

I have some concerns/comments…

Again, feel free to reach out directly to  me or post about them in the Q&A forum.

How do I ... ?

Plan a CCR bailout ?

Make a plan with CCR levels, add bailout in the "deco gas" section, and be sure to mark them as BAIL. Both gases marked as BAIL and OC are used for bailout (OC ones are also used for switching to OC deco). Once you have any levels with a CCR setpoint, deco gases can be marked as BAIL, and this means that this gas is only to be used when doing bailout calculation.

Now tap any level/decostop, and a action sheet will pop-up offering to show a bailout from this spot.

Do a lost gas plan ?

Make a plan, and at the bottom of the plan you'll find the gas consumption. Tap a deco gas and a action sheet will pop-up offering a lost gas plan for losing this gas.

CCR Bailout and repetitive dives, how do I ... ?

If you've done a CCR bailout and you want to know what happens to the rest of the dives (assuming you're not calling it quits for the day), you'll have to change the plan, in which you bailed, or the repetitive dives will be calculated wrong. Since Baltic supports bailout planning for both levels and stops, it's fairly simple to capture this for repetitive dives by modifying levels and gases.

Say that you bailed at the 70fsw/21msw stop, go to your plan and change your bailout gasses (that would cover the 70fsw/21msw stop) from BAIL to OC and set the start depth accordingly if necessary. The plan will now reflect the bailout, and subsequent dives in the workset will take this into account.

Plan a CCR setpoint for deco ?

If you have a plan with a level that is using CCR, you can plan a setpoint change by adding a "deco gas". When you add a deco gas in a dive with CCR levels, the CCR column will offer the options of "BAIL", "OC" or a setpoint. Set the new setpoint and depth (and the diluent mixture if necessary) and this new setpoint will be used from that depth.

Plan a CCR dive with OC deco ?

If you have a plan with a level that is using CCR, you can plan for switching to OC deco by adding a "deco gas". When you add a deco gas in a dive with CCR levels, the CCR column will offer the options of BAIL, OC or a setpoint. Set the desired gas and set the CCR column to OC. The gas will now be used as OC deco from the given depth.

Algorithms

Altitude Correction, Fresh Water and Surface Pressure Correction

When changing the altitude in Baltic, the generated plan is still computed assuming salt water and sealevel pressure when computing depths, just with a lower surface pressure. This means that the plans are suitable for using gauge that's calibrated for ocean diving, not a gauge calibrated for fresh water and with a surface pressure of less than 1bar.

What tables/algorithms does Baltic use ?

Baltic implements VPM/B and ZHL16B with Gradient Factors, also known as "Bühlmann with GF". It is not based on table look-ups.

What ZHL16 values are used ?

For ZHL16, the a and b coeffecients are the B table values (ZHL16B). The halftimes used (0.9 and upwards) are ;

• N₂: 4, 8, 12.5, 18.5, 27, 38.3, 54.3, 77, 109, 146, 187, 239, 305, 390, 498, 635
• He: 1.88, 3.02, 4.72, 6.99, 10.21, 14.48, 20.53, 29.11, 41.20, 55.19, 70.69, 90.34, 115.29, 147.42, 188.24, 240.03

Prior to the 0.9 release, the 1b N₂ halftime of 5 minutes was used.

Where did the algorithm implementations come from ?

Both were implemented for another project in 2007 and 2008 respectively. The ZHL16 implementation is based on available litterature, such as Dr. Bühlmann's Tauchmedizin, Dr. Wienke's Technical Diving in Depth and Erik C. Bakers many papers on decompression calculations.

The VPM/B implementation is a reimplementation of Erik C. Baker's reference fortran implementation. It is not a f2c generated version.