Who must inspect fixed fire extinguishers?

The correct choice indicates that fixed fire extinguishers must be inspected by qualified contractors. This is important because fire extinguishers are critical safety devices that require proper maintenance and testing to ensure they function effectively during an emergency. Qualified contractors are typically certified or trained in the relevant codes and standards, such as those established by organizations like the National Fire Protection Association (NFPA). They possess the technical knowledge and equipment necessary to perform thorough inspections and maintenance.

Regular inspections carried out by qualified contractors ensure compliance with local and national fire safety regulations, which can vary by state or municipality. These experts can also identify issues such as pressure problems, corrosion, or other defects that an untrained individual might overlook, thereby ensuring that the extinguishers are not only present but are also operable when needed.

The other answer choices imply that inspection can be done by individuals without the requisite training or expertise, which can lead to inadequate maintenance and pose serious risks during a fire event. It's essential that inspections are conducted by those who understand the specific requirements and safety protocols associated with fire extinguishers.