Does every patient being evaluated or treated for a behavioral condition require 1:1 monitoring? What is the monitoring requirement for patients at high risk for suicide?

Any examples are for illustrative purposes only.

No, not all patients being evaluated or treated for a behavioral condition require 1:1 monitoring. 

In units/areas that contain ligature and/or other safety risks, patients determined to be at high-risk for suicide must be under continuous observation with the ability to immediately intervene through the use of 1:1 observation - 1 qualified staff member to 1 high risk patient. A qualified staff member is one that has been trained and has demonstrated competence in working with suicidal patients and performing 1:1 observation. 

In inpatient psychiatric units/designated psychiatric areas that are ligature resistant and free from other safety risks, it is up to the organization to determine monitoring requirements for patients determined to be at high-risk for suicide and define such in their policy. 

Additional Resources 
Suicide Prevention Portal