Open the VPM Deco algorithm code for Shearwater computers

Upgrade your Predator, Petrel, or Perdix dive computer to VPM-B decompression. This upgrade gives you the option of using the standard GF deco or switching the VPM-B algorithm. To purchase, please enter your computer's serial number in the box below and complete the order as usual. Your unlock code will be emailed to you within 48 business hours. Note: you will also need to update your firmware to the latest version. VPM Bubble Models. VPM or the Varying Permeability Model is a decompression algorithm that attempts to model the behavior of bubbles within the human body during decompression. The algorithm was initially developed by David Yount in laboratory testing and coded into Fortran by Erik Baker. The Shearwater Implementation. Shearwater Research has implemented VPM-B according to the original Erik Baker Fortran specification. In addition to implementing the Baker model, Shearwater Research has added a new option. VPM-B dive profiles often have deep stops to control bubble formation with reduced time at shallow depths. The reduced shallow depth time can be quite aggressive with VPM-B so Shearwater Research has included a VPM-B Gradient Factor Surfacing (GFS) option. VPM-B/GFS allows VPM-B dives to be executed while ensuring that a gradient factor of 90% is never violated. Features Adjustable conservatism from 0 to +5. VPM-B and VPM-B/GFS (Gradient Factor Surfacing) available as a firmware option to existing Shearwater Predators.