Before servicing a pressurized hydraulic reservoir, what must be done?

Before servicing a pressurized hydraulic reservoir, relieving the air pressure is a crucial step. In hydraulic systems, the presence of pressurized air can pose significant safety hazards. Pressurized air can lead to sudden fluid release, which can cause dangerous splashes or sprays of hydraulic fluid, potentially injuring personnel or damaging equipment.

By relieving the air pressure, you ensure that the system is at a safe pressure level before any servicing takes place. This step is essential for maintaining safe working conditions and preventing accidents.

Additionally, while checking the hydraulic fluid level, evacuating the fluid, or disconnecting the power source may be part of the maintenance process, they do not directly address the immediate safety concerns associated with existing pressurization in the system. Ensuring the pressure is relieved comes first to create a safe environment for any further maintenance actions to follow.