The Personnel Protection System

What is the Personnel Protection System?

The Personnel Protection System (PPS for short) is a lab-wide system that is primarily designed to limit the harm that can be done to lab personnel by accelerator specific hazards. These hazards most often include prompt radiation and oxygen deficient atmospheres. Operators mostly interact with the PPS through the PPS rack and through securing or surveying areas.

The PPS Rack

The PPS rack may be the single most eye-catching thing in the main control room. It is the tall, yellow box in the corner near the board used for tracking validation results. Almost all operators have a healthy fear of this box. Operators interface with the rack to complete a variety of tasks: changing the ACS status for areas, responding to RCS and ACS alarms, changing machine modes, setting attenuator thresholds, and setting beam destinations. It is the main way operators interact with the PPS, making the PPS rack an invaluable tool and very important tool for operators to understand.

ODH

Oxygen Deficiency Hazards (ODH) are quite specific to accelerators. FRIB employs many superconducting magnets in its operations and these superconductors need to be cooled to supercriticality. To do this FRIB has a large cryoplant that uses liquid nitrogen and helium, cooled to 4K, as coolants for these magnets. The existence of these cryogens, and the way they are employed, creates the possibility of there being an oxygen deficient atmosphere in the same space as people working. To combat this the PPS is connected to many ODH monitors spread throughout the lab in places where cryogens are frequently used. The back side of the PPS rack contains an HMI that provides great overviews on where monitors are located and how many there are in each area.

RSS

The Radiation Safety System (RSS)

ACS

A subset of RSS

RCS

A subset of RSS

Trips and Faults

Securing

Alarms