Final answer:
Only a qualified person, certified inspector, or experienced chief engineer is permitted to adjust safety valves, ensuring safe and proper functioning under emergency conditions.
Step-by-step explanation:
Adjustment of safety valves is a critical procedure that must only be performed by individuals with the proper knowledge and authorization to ensure the safety of a facility and its operations. The person permitted to adjust safety valves is typically a qualified person who has received specialized training and possesses the necessary skills to undertake this task. In some cases, regulations may allow a certified inspector or an experienced chief engineer to adjust safety valves if they meet the qualifications. However, it is crucial that this task is performed by someone authorized and capable to ensure that the safety valves function correctly under emergency conditions.