Ace the CBET Challenge 2026 – Master Biomedical Equipment with Style!

The total lung capacity (TLC) represents the maximum amount of air that the lungs can hold and is comprised of several distinct components. The correct equation is a summation of the four key lung volume components: Inspiratory Reserve Volume (IRV), Tidal Volume (TV), Expiratory Reserve Volume (ERV), and Residual Volume (RV).

- Inspiratory Reserve Volume is the amount of air that can be inhaled after a normal inhalation.

- Tidal Volume is the volume of air inhaled or exhaled during normal breathing.

- Expiratory Reserve Volume is the amount of air that can be forcibly exhaled after a normal exhalation.

- Residual Volume is the air remaining in the lungs after a forced expiration, which cannot be voluntarily exhaled.

By summing these volumes, the equation accurately defines the total lung capacity, as it accounts for all the usable volumes of air within the lungs, including both the air that can be actively inhaled or exhaled and the air that remains in the lungs after full exhalation.

Thus, option B provides a comprehensive representation of total lung capacity, capturing all the different components involved in lung function.