What is the correct sequence for attaching the air supply to the drill motor?

Attaching the air supply to the drill motor after inserting the drill bit is the correct procedure because it ensures safety and proper functionality. When the drill bit is already in place, you are less likely to have unexpected movements or engage the drill inadvertently while attempting to connect the air supply. This reduces the risk of accidents, such as the drill rotating unexpectedly, which could lead to injury. Additionally, having the drill bit installed before air is supplied helps ensure that the setup is complete and allows for immediate use once the air is connected, leading to more efficient workflow.

Attaching the air supply before the drill bit can lead to safety hazards and is not the standard practice, as it can cause the drill to engage while you're still working on the setup. Adjusting the drill speed should also be done after the air supply is connected and the drill is secured with the bit, ensuring that you’re working with a stable and safe setup. Lastly, connecting the air supply only when the drill is off may be overly cautious; it's generally not necessary as long as proper procedures are followed, such as inserting the drill bit first.