2022 Volume 37 Issue 4 Pages 699-707
Objective: To investigate the number of ventilations under various ventilation conditions of a cardiovascular medical examination car and to propose appropriate ventilation methods.
Methods: A cardiovascular medical examination car was filled up with high-concentration CO2 gas with dry ice under the following conditions: (1) each window opened at 5 cm, (2) “Low” front and rear ventilation fans, (3) “High” front ventilation fan and “Low” rear ventilation fan, (4) “Low” front and rear ventilation fans and each window opened at 5cm and (5) “High” front ventilation fan and “Low” rear ventilation fan and each window opened at 5cm. CO2 ventilation is performed under five conditions of window opening 5 cm. The number of ventilations was determined using the Seidel equation based on the change in the gas concentration.
Results: Conditions (1), (4), and (5) resulted in more than 12 ventilations per hour in the US Centers for Disease Control and Prevention (CDC) and infection isolation wards in Japan. Specifically, conditions (4) and (5) demonstrated at least 20 ventilations per hour.
Conclusions: If conditions (1), (4), and (5) represent sufficient ventilation frequency and the adverse effects due to the noise of the ventilation fan are minimal, condition (4) can be recommended for use in a cardiovascular medical examination car.
