Decompression data display devices

A decompression data display device, comprising:

• pressure sensing means for sensing a pressure of an environment in which a diver is;
• determining means for determining whether a plurality of respective tissues of the diver's body having different half saturation times are absorbing or discharging an inert gas;
• tissue inert gas level data calculating means for calculating from the pressure sensed by said pressure sensing means data on a level of an inert gas in each of the tissues in accordance with an arithmetic expression which includes the half saturation time as an operand when said determining means determines that the tissue is absorbing the inert gas, and for calculating from the pressure sensed by said pressure sensing means data on the level of an inert gas in each of the tissues in accordance with a version of the arithmetic expression in which the half saturation time is modified with a coefficient varying in dependence on each of the tissues when said determining means determines that the tissue is discharging the inert gas;
• decompression data calculating means for calculating decompression data from data on the inert gas level in each of the respective tissues calculated by said tissue inert gas level data calculating means;
• and
• display means for displaying the decompression data calculated by said decompression data calculating means.

A method of obtaining data on a level of an inert gas in each of a plurality of tissues of a diver's body, comprising the steps of:

• sensing the pressure of an environment in which the diver is;
• determining whether the plurality of tissues of the diver's body are absorbing or discharging an inert gas;
• calculating from the sensed pressure data on the level of the inert gas in each of the tissues in accordance with a first arithmetic expression when it is determined that the tissues are absorbing the inert gas, and for calculating from the sensed pressure data on the level of the inert gas in each of the tissues in accordance with a second arithmetic expression different from the first arithmetic expression when it is determined that the tissues are discharging the inert gas;
• calculating decompression data from data on the level of the inert gas in each of the tissues;
• and
• displaying the calculated decompression data.

A method of obtaining data on a level of an inert gas in each of a plurality of tissues of a diver's body, comprising the steps of:

• sensing the pressure of the environment in which a diver is;
• determining whether the plurality tissues of the diver's body having different half saturation times which are the periods of time taken for the inert gas partial pressures in the respective tissues to reach 50% of their saturation values are absorbing or discharging an inert gas;
• calculating from the sensed pressure data on the level of an inert gas in each of the tissues in accordance with an arithmetic expression which includes the half saturation time as an operand when it is determined that the tissue is absorbing the inert gas, and calculating from the sensed pressure data on the level of an inert gas in each of the tissues in accordance with a version of the arithmetic expression in which the half saturation time of that tissue is modified with a coefficient varying in dependence on that tissue when it is determined that that tissue is discharging the inert gas;
• calculating decompression data from data on the calculated level of the inert gas in each of the tissues;
• and
• displaying the calculated decompression data.