What must be assessed during a medical evaluation for a respirator wearer's suitability?

During a medical evaluation for a respirator wearer's suitability, it is crucial to assess heart health and respiratory function. This evaluation focuses primarily on the aspects that directly impact a person's ability to safely use a respirator while performing their job duties.

Heart health is vital because if a wearer has underlying cardiovascular conditions, the physical exertion associated with using a respirator could exacerbate these issues and result in serious health risks. Similarly, assessing respiratory function is essential, as the respirator's effectiveness depends on the user's ability to breathe properly while it is in use. Conditions such as asthma, chronic obstructive pulmonary disease (COPD), or other respiratory illnesses could hinder a person's capacity to use a respirator safely and effectively.

Other options like joint flexibility and strength, vision and hearing abilities, and weight and height measurements, while important in occupational health and safety assessments, do not directly address the critical functions of the cardiovascular and respiratory systems in relation to respirator use. The focus on heart and respiratory health ensures that individuals are fit to endure the potential physical stress of using breathing apparatuses in their work environment.