Albert Alois Bühlmann (16 May 1923 – 16 March 1994) was a Swiss physician who was principally responsible for a number of important contributions todecompression science at the Laboratory of Hyperbaric Physiology at the University Hospital inZürich, Switzerland.[1][2][3] His impact on diving ranged from complexcommercial andmilitary diving to the occasionalrecreational diver.[2] He is held in high regard for his professional ethics and attention to his research subjects.[4][5]
In 1959,Hannes Keller became interested in deep diving and developed tables for mixed-gas decompression. Not a diver himself, Bühlmann was intrigued by project and suggested suitablebreathing gases.[3][8] Keller successfully tested his idea in theLake Zurich where he reached a depth of 400 feet and thenLake Maggiore where he reached a depth of 728 feet.[2][9]
The naming convention he used to describe his algorithms, for example, ZH-L16, comes from Zürich (ZH), limits (L) and the number of tissue compartments or M-value sets used (16).
In 1962, Keller set a new world record when he reached a depth of 1000 feet off the coast ofCalifornia utilizing Bühlmann's algorithm in a study funded by theUnited States Navy.[2][9]
Two out of eight Swiss military divers suffered decompression sickness following dives 1800 meters above sea level inLake Silvaplana.[2] Bühlmann recognized the problems associated withaltitude diving,[13][14][15] and proposed amethod which calculated maximum nitrogen loading in the tissues at a particular ambient pressure.[6][16] The tables developed were adopted by the Swiss military in 1972.[2] An expedition toLake Titicaca at 3800 meters above sea level in 1987 revealed no decompression issues while utilizing Bühlmann's ZH-L16 algorithm.[2] In addition to altitude diving, his calculations also include considerations for repetitivedive profiles.[17]
The results of Bühlmann's research that began in 1959, was published in a 1983 German book entitledDekompression-Dekompressionskrankheit (Decompression-Decompression Sickness).[6] An English version of this book became available in 1984.[1] The book was regarded as the most complete public reference on decompression calculations and was used soon after in codingdive computeralgorithms.[18] Two follow-up books were published in 1992 and 1995.[19][20]
Versions of Bühlmann's ZHL-16 model have been used to generate the standard diving tables for a number of sports diving associations. Max Hahn used Bühlmann's model to develop the Deco '92 Tables used by theSwiss Underwater Sport Association and theAssociation of German Sports Divers, andBob Cole and Bühlmann developed theSub-Aqua Association (SAA) Bühlmann System in 1987, which used the tables and a set of instructions for their use in recreational divingwithout decompression stops.[18] The tables are still used in the 2020s and remain popular, while manydive computers use variations of the ZHL-8, ZH-L12, or ZHL-16 algorithm.
^abBühlmann, Albert Alois (1984).Decompression-decompression sickness [Translation of: Dekompression-Dekompressionskrankheit]. Translated by Gilbert Paul Michel. Berlin, Heidelberg: Springer-Verlag.doi:10.1007/978-3-662-02409-6.ISBN978-3-662-02409-6.
^abcdefghijklmnVöllm, Ernst B.; Götte, Georg (1994). "Leading diving researcher dies unexpectedly: Albert A Bühlmann, 1923 - 1994".Pressure, newsletter of the Undersea and Hyperbaric Medical Society.23 (3):1–3.ISSN0889-0242.
^Schreiner, Heinz (1994). "Prof. Albert A Bühlmann: Maker of diving history".Pressure, newsletter of the Undersea and Hyperbaric Medical Society.23 (3): 3.ISSN0889-0242.
^Bühlmann, Albert A. (1973). "Ethical considerations in hyperbaric research--situation in Switzerland".Försvarsmedicin.9 (3):367–8.PMID11661279.
^abcdBühlmann, AA (1984).Decompression-Decompression Sickness. Berlin New York: Springer-Verlag.ISBN0-387-13308-9.
^Powell, Mark (2008-10-18).Deco for Divers: Decompression Theory and Physiology. AquaPress.ISBN1-905492-07-3.
^Bühlmann Albert A (1989). "[Decompression problems in diving in mountain lakes]".Schweiz Z Sportmed (in French).37 (2):80–3, discussion 99–102.PMID2799365.
^Bühlmann Albert A (1984). "[Decompression during lowered air pressure]".Schweiz Med Wochenschr (in German).114 (26):942–7.PMID6087447.
^Bühlmann Albert A, Schibli R, Gehring H (March 1973). "[Experimental studies on decompression following diving in mountain lakes at reduced air pressure]".Schweiz Med Wochenschr (in German).103 (10):378–83.PMID4144210.
