Final answer:
The technician should intervene when the arterial chamber is 95% full during safety checks.
Step-by-step explanation:
The intervention that is required in this situation is option D, which states that the arterial chamber is 95% full.
When performing safety checks, it is important to ensure that the equipment is functioning properly and is set up correctly. In this case, an arterial chamber that is 95% full may indicate an issue with the measurement or flow of blood pressure.
It is important to address this issue to ensure accurate and reliable blood pressure readings.