Final answer:
Fire extinguishing refillable containers are checked once a year to verify their weight and pressure. Regular checks and maintenance help ensure the reliability of fire extinguishers.
Step-by-step explanation:
Fire extinguishing refillable containers are usually checked once a year for weight and pressure. This is important to ensure that the extinguisher is functioning properly and has enough extinguishing agent to use in case of a fire emergency. The weight of the container is checked to make sure it is still within the acceptable range, and the pressure is checked to verify that it is at the required level for effective operation. Regular checks and maintenance help ensure the reliability of fire extinguishers.