Which of the following statements are true about the routine maintenance of a UPS?

Routine UPS maintenance is preventive by design, so it must cover bothenvironmental conditionsandequipment operating status, not only alarms. The equipment room environment directly affects UPS reliability: high temperature accelerates capacitor aging, reduces battery/rectifier reliability, and may trigger derating; improper humidity increases the risk of condensation or electrostatic discharge; dust and poor housekeeping raise the risk of blocked airflow and overheating. Therefore, theenvironment checkin option A is a standard routine item. Option B is also essential because O&M personnel must confirm the UPS is innormal operating mode, verify no hidden alarms exist in the event log, and ensure the load level is within the recommended range to maintain redundancy and efficiency. Option C is true because fans are typical “wear-out” components; abnormal noise or speed changes often appear before a failure and can be detected early through inspection. Option D is false: absence of a front-panel alarm never replaces onsite environmental inspection and basic preventive checks.