Which activities can a Type B fire extinguisher license perform?

A Type B fire extinguisher license specifically pertains to the service and maintenance of extinguishers designed for flammable liquids and gases, such as petroleum products, alcohols, and solvents. Therefore, the correct answer indicates that individuals with this license are authorized to perform maintenance and recharging of water-based extinguishers, which includes those designed to handle B-class fires.

Water-based extinguishers are often used in conjunction with Type B extinguishers, especially in situations where a combination of fire risks is present. Ensuring that these extinguishers are adequately maintained and recharged is crucial for their effectiveness in emergency situations. This type of maintenance may include checking the pressure, inspecting for any damage, and refilling the extinguisher with the proper extinguishing agent.

In contrast to this, the other choices include activities that may not fall within the scope of a Type B license, such as conducting hydrostatic tests or servicing all types of extinguishers, which would typically require additional certifications or licenses beyond just Type B. Additionally, limiting maintenance to just external aspects of foam extinguishers is insufficient as it does not encompass the comprehensive responsibilities expected of someone with a Type B designation.