Final answer:
A portable, refillable fire extinguisher can lose up to 10% of its net content or weight before it must go through maintenance.
Step-by-step explanation:
A portable, refillable fire extinguisher can lose up to 10% of its net content or weight before it must go through a maintenance process. This means that if the extinguisher loses more than 10% of its content, it needs to be refilled or serviced. For example, if the original weight of the extinguisher is 100 grams, it would need to be serviced if it loses more than 10 grams.