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 objective is not to explain technical terms or the difference between decompression models. Another way to look at decompression sdi tdi erdi pfi. Decoplanner has been used to calculate a series of progressively more aggressive long and deep dives. Basic decompression theory and use of decompression tables is part of the theory component of training for commercial divers, and dive planning based on decompression tables, and the practice and field management of decompression is a significant part of the work of the diving supervisor. Vplanner is a decompression program that uses the varying permeability model. Eric baker, understanding mvalues eric bakers excellent article which explains the principles of mvalues eric baker, clearing up the. David yount, erik baker and i collaborated to extend the vpm decompression. Dplan has a wide array of decompression models to choose from. Decompression physics, the release of pressure and the opposition of physical compression decompression altitude. When used together, gfhigh and gflow become the high and low factors in the baker gradient factor method. Unlimited amount of travel and decompression gas mixes. Jan 12, 2016 most modern decompression software provides either conservatism settings in verbal terms or numbers or gradient factors.
Through the use of widelyavailable desktop computer programs, technical divers rely on this model for their decompression safety. Upgrade to vpm deco algorithm for shearwater research. Mar 26, 2015 decompression is the process of restoring compressed data to its original form. Vplanner is a decompression program that uses the varying permeability model vpmb for decompression profiles. They were the original deepstop decompression programs used by technical divers. Decotengu is python dive decompression library to experiment with various implementations of the buhlmann decompression model with erik baker s gradient factors other decompression models might be possible in the future the results of decotengu calculations are decompression stops and tissue saturation information. This is based on erik baker s article on deep stops which was published in immersed magazine and is widely available on many diving web sites. Another method used were gradient factors created by erik baker. Decotengu is python dive decompression library to experiment with various implementations of buhlmann decompression model with erik baker.
Here are links to articles and publications on the vpm and decompression. The following material includes publications as well as behindthescenes discussions of technical aspects of the vpm as applied to the real world of diving. If you need a more sophisticated zipunzip application, have a look at our zipagent software. Mar 05, 2012 the work of professor albert buhlmann, max hahn, david yount, eric maiken, erik baker, bruce weinke, anders ersson, et al is thoughtprovoking, sometimes contentious, and above all gives armchair decompression theorists fodder for the technical diving communitys analogue of a university faculty cocktail party debate. The diver identifies the requirement for decompression stops, and if they are needed, the depths and durations of the stops, by using decompression tables, software planning tools. This value can be used as a rough measure of the current decompression risk. It utilizes the varying permeability model vpmb and buhlmanns decompression algorithm with erik baker s gradient factors for mixed gas decompression in opencircuit oc and closedcircuit ccr diving mode. The programs available on this site were the first bubble model programs to be used for sport mixedgas decompression diving. Most modern decompression software provides either conservatism settings in verbal terms or numbers or gradient factors. Decompression is considered important, as compressed data. Supports air to trimix any combination of o2hen2, with an unlimited number of decompression gases. We are certain that dr buhlmann and erik baker explain their.
In 2002, after considerable diver feed back, the model was further developed by erik baker, to the current vpmb model. Understanding mvalues by erik baker introductory deco lessons by erik baker diy decompression by stuart morrison. First used for oxygendriven decompression from air and nitrox diving in 1992, vpm field deployment predated release of commercial deep stop programs such as gfdriven decoplanner in 1998, or most recently, the rgbmbased gap in 2003. Deco planner manual this document is written to support. Multideco dive decompression planning software multideco is a decompression program that uses the varying permeability model vpmb and the buhlmann zhl16 for decompression profiles.
Vplanner is a decompression program that uses the varying permeability model for decompression profiles. Similar to compression of data, decompression of data is also based on different algorithms. Decotengu is python dive decompression library to experiment with various implementations of buhlmann decompression model with erik baker s gradient factors. Decompression is the process of restoring compressed data to its original form. Hlplanner is completely free mixed gas decompression software utilising the vpmb algorithm.
Baker the old adage, an ounce of prevention is worth a pound of cure, is certainly applicable to the various symptoms of decompression sickness dcs. It utilizes the varying permeability model vpmb and buhlmanns decompression algorithm with erik bakers gradient factors for mixed gas decompression in. Beginning may 25, 2016, decoplanner will be included in tech 1, tech 60, tech 2, cave 1, and cave 2 course registrations. Ultimate planner is a decompression planning software program incorporating both varying permeability model with boyles law compensation vpmb and buhlmanns published zhl16b and zhl16c, along with zhl16d based on his recommendations with erik bakers gradient factors for oc and ccr dives. Includes sections on technical diving and decompression theory. Bubble decompression strategies by eric maiken vpm decompression site by eric maiken confessions of a mortal diver by richard pyle the importance of deep stops by richard pyle halftimes explained by mark powell deco lessons by erik baker pdf oxygen toxicity calculations by erik baker pdf clearing up the confusion about deep stops by erik baker pdf. Before delving into the vpm, its obligatory that one fully understands haldanean models. Vplanner vpmb dive decompression software hhs software corp. The vplanner program was developed by ross hemingway, and presents the vpmb algorithm inside a complete and useful windows dive decompression program. If that sounds confusing, then recommended reading is erik baker s paper, clearing up confusing about deep stops. The practice of making decompression stops is called staged decompression, as opposed to continuous decompression.
Decompression software such as departure, decoplanner, ultimate planner, zplanner, vplanner and gap are available, which simulate the decompression requirements of different dive profiles with different gas mixtures using decompression algorithms. The deco profiles will start deeper than traditional models and account for micro bubble growth and keep overall supersaturation lower, and giving a better. Data decompression is required in almost all cases of compressed data, including lossy and lossless compression. Buehlmanns 1990 zhl16b model is designed for predive planning, and is the most widely used decompression model in the world. Hlplanners engine is loosely based on erik baker s fortran 77 code, available in the public domain.
Developed by decompression researcher erik baker in the 1990s. Jdeco is the first and only dive decompression program that is available for java enabled mobile phones and pdas. Clearing up the confusion about deep stops by erik c. In your account, click on the files tab to reach your download link. Details of the vpm microscopic bubble nuclei have been observed in many types of aqueous watercontaining media under equilibrium conditions. Links to vpm decompression programs and information. This in essence was a modification of buhlmann or any other halftime model by changing the gas pressures tensions allowed upon surfacing as well as setting a deeper decompression point which then recomputed the slope to the surface where the slope would be determined. A diver can modify the total dive time easily by even tens of minutes with these settings, not to mention also the decompression gas needed. A value of 100% buhlmanns originally allowed supersaturation limit is now generally accepted to be too risky. During 1999 and 2000, david yount, erik baker and i collaborated to extend the vpm decompression algorithm to model repetitive, mixedgas decompression diving. Decompression planning for tmx dives between 120200m. Purely webbased scuba diving decompression software, that supports buhlmann gf with gradient factors, and the variable permeability model vpmb decompression models, multiple gasses, multiple stageslevels, and complex shaping. Decochek desktop is free to download, by clicking on links at bottom of page this unregistered copy is fully functional to a depth of 40mft. It was further developed by david yount, eric maiken, and erik baker from.
First used for oxygendriven decompression from air and nitrox diving in 1992, vpm field deployment. No, unzip is only a small decompression program for people not having any decompression program installed. This software is experimental, it probably contains bugs and should not be relied upon for actual dives. To this end he was assisted greatly by information provided by erik baker, an expert in decompression theory, some of whose published articles appear elsewhere in this manual. Jdeco dive decompression software for java mobile devices. When your purchase is complete your file will appear in your my account section accessed from your personal menu on the right. Decompression has several meanings, some of which are covered by several articles. In the case of underwater diving and compressed air work, this mostly involves ambient pressures greater than the local surface pressure, but astronauts, high altitude mountaineers, and.
The algorithm was initially developed by david yount in laboratory testing and coded into fortran by erik baker. The current stateoftheart in vpm calculations is erik bakers open source code. Scottish scientist john scott haldane 18601936 is generally considered the founding father of modern decompression theory. Decochek decompression software welcome to, home of the most advanced and flexible dive planning software available to technical divers today. Special thanks to erik baker, eric maiken and eddie brian for co mments and permission to use the graphics. Erik baker s recently released open source code fortran program incorporates the results of our work. For this purpose the following sources are worth mentioning. This software is provided free of charge for experienced mixed gas rebreather divers to evaluate mvalue gradient profiles based on erik baker s mvalue gradient calculations and the buhlmann zhl16b decompression model. A decompression algorithm is used to calculate the decompression stops needed for a particular dive profile to reduce the risk of decompression sickness occurring after surfacing at the end of a dive. Multideco is a decompression program that uses the varying permeability model.
I received this email from one of my fellow shearwater. Written in javatm so runs on pc, mac, linux or any computer supporting java runtime 1. The vpmb decompression model is well suited to todays technical diving. Model was originally developed by yount and hoffman in 1986. Apeks quantum, buhlmann, decompression, dive computer, diving, gradient factors, nitrox, outdoors, scuba, scuba diving, scuba equipment, scuba instructor, scuba training, shearwater, shearwater pursuit, technical diving, zhl16c add a comment. Data decompression, the action of reversing data compression. Ultimate planner is a decompression planning software program incorporating both varying permeability model with boyles law compensation vpmb and buhlmanns published zhl16b and zhl16c, along with zhl16d based on his recommendations with erik baker s gradient factors for oc and ccr dives. Erik bakers open source fortran program implements the. Includes decompression stops, gas usage, cns tracking, otu tracking, surface interval tracking and many other features. The vpmb model produces consistent decompression plans for the entire range. The zhl16c version is designed for realtime use in dive computers, and is slightly more conservative. Rather than using a fixed conservatism value, it uses two which adapt as the deco progresses. Most dive computers or decompression planning software allow the user. Buhlmann diving decompression model with gradient factors by erik baker zhl16bgf and zhl16cgf.
Vpmb 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 can be used to generate decompression schedules for a particular dive profile, decompression tables for more general use, or be implemented in dive computer software. The multideco program was developed by ross hemingway, and presents the vpmb algorithm inside a complete and useful windows dive decompression program. This is a tool meant for executing the buhlmanngf with gradient factors and zhl tissues a, b and c and the variable permeability model b vpmb by erik baker algorithms in your browser. Hlplanner s engine is loosely based on erik baker s fortran 77 code, available in the public domain. Recreational pursuits july 2, 2009 posted by chris sullivan in equipment, technical diving. Like gfhigh, extremely low values of gflow will result in unrealistically long decompression times. Currently implements the buhlmann zhl16c with erik baker s gf algorithm. Developed by decompression researcher erik baker in the 1990s, gradient factors gf are commonly used with buhlmann decompression models to adjust for conservatism. They were the original deepstop decompression programs used by technical.
In the last century 18961907 haldane experimented on goats in an attempt to find a solution to the problem of caisson disease, experienced by men working in pressurized bridge and tunnel construction areas. Gf are presented as a fraction of the maximum inert gas supersaturation or mvalue that can be tolerated by each of the theoretical tissue types or compartments considered by the buhlmann model without resulting in dcs. Baker the old adage, an ounce of prevention is worth a pound of cure, is certainly applicable. In 2002, after considerable diver feed back, the model was further. Decompression stops regulated solely by this parameter are noted as gflow stops in the program output. The diver identifies the requirement for decompression stops, and if they are needed, the depths and durations of the stops, by using decompression tables, software planning tools or a dive computer. Decoplanner 3 also comes bundled with gues divelog software. Aug 07, 2019 bubble decompression strategies by eric maiken vpm decompression site by eric maiken confessions of a mortal diver by richard pyle the importance of deep stops by richard pyle halftimes explained by mark powell deco lessons by erik baker pdf oxygen toxicity calculations by erik baker pdf. Ultimate planner decompression planning software scubaboard. All models run within the same neohaldanian framework. Decompression theory links and resources technical. It was further developed by david yount, eric maiken, and erik baker from 1999 to 2001. It enables them to expand zip files attached to their emails or stored on their hard drives at no cost.
Erik baker and eric maiken were central to bringing the model to completion. Decompression theory is the study and modelling of the transfer of the inert gas component of breathing gases from the gas in the lungs to the tissues and back during exposure to variations in ambient pressure. Decompression theory links and resources technical scuba. Within 5 minutes of using this product i experienced more relief than all of those visits combined. Developed by simon tranmer, with assistance by erik baker and gue representatives from around the world, decoplanner is available through gue for windows 9598nt 4. Baker is a big fan of deep stops you can probably guess that im a big fan also, which are short decompression stops at greater than usual depths to allow compartments with shorter halftimes to offgas a bit. Mvplan dive planner a multiplatform mvalue gradient decompression program features. Clearing up the confusion about deep stops, by eric baker. These latest vpm methods now underpin a number of freeware decompression programs. I have had a sciatic problem for 3 years and have had chiropractic adjustments and massage therapy the entire time.