Ventilatory response to carbon dioxide during moderate exercise

Abstract

Elevated carbon dioxide (CO2) concentration is one of the most important physiological stressors with closed-circuit breathing-apparatus (CCBA). We determined the ventilatory response to CO2 during moderate exercise by measuring the relationship between V(E) and P(ET)CO2. Based on our findings, it is recommended that the permissible inhaled CO2 limit for CCBA in the Japan Industrial Standard (JIS) be lowered from 3% to 2%, and that the members of a rescue or fire fighter team who use CCBA be selected on the basis of their ventilatory sensitivity to CO2.