What types of gas systems does NFPA 99 apply to?

NFPA 99 applies to a comprehensive range of medical gas systems used in healthcare facilities, which includes medical air, oxygen, nitrous oxide, and vacuum systems. This is because these gas systems are critical for patient care, anesthesia, and medical treatments in various clinical settings.

The standard provides requirements ensuring safety, reliability, and proper performance of these systems to protect patients, healthcare workers, and the facility itself. Medical air is essential for respiratory support, oxygen is vital for treating patients with respiratory issues, nitrous oxide is commonly used in anesthesia practices, and vacuum systems are crucial for removing waste gases and fluids during medical procedures.

The other options focus on more limited or specific categories of gas systems, which do not encompass the full range that NFPA 99 covers. Therefore, B captures the entirety of systems addressed in the standard, establishing its pertinence to health and safety regulations in medical environments.