What is the first step when using a fire extinguisher?

The initial step in using a fire extinguisher is to pull the pin. This action is essential as it unlocks the operating lever and allows you to use the extinguisher effectively. The pin serves as a safety mechanism to prevent accidental discharge, ensuring that the extinguisher cannot be activated until the pin is removed. Once the pin is pulled, the extinguisher is ready for use, and the operator can then proceed to direct the nozzle at the flames and push the handle to discharge the agent. This sequence of actions is crucial to ensuring safety and efficiency in extinguishing the fire.