The TJNAF Personnel Safety System (PSS) protects personnel from exposure to high radiation levels and other hazards in the accelerator enclosure associated with operation of the electron beam. PSS access controls include magnetically locked and interlocked doors and gates, keybanks for controlled accesses and status indicators. Other functions of the PSS include direct beam sensing and termination capabilities, radiation monitoring and emergency shut off switches.

Status displays you should recognize include:
Machine State status indicator - These automatic signs are located at each main access point to the beam enclosure. Access to the enclosure is permitted only during Restricted Access or Controlled Access modes. You must only then enter if all other requirements for entry are met. Never attempt to enter the enclosure unless you are sure the accelerator is in safe state.
Magenta beacons (or strobes) - The magenta beacon signifies a condition in which access to an area is not permitted (when interlocks are engaged). These beacons are located at access points which do not have Machine State status panels. These beacons may also be used in off-site areas to warn of operational radiation producing devices. The beacon will be accompanied by radiological postings indicating the type of radiological area denoted by its operation. NEVER attempt to enter an area designated by an operating beacon.
Run/Safe Box - indicate the status of the accelerator during tunnel access. Run/safe boxes are located strategically within the beam enclosure and provide an indication of the machine state as well as a means to terminate unsafe conditions in the event of an accident or other failure. When, you enter the beam enclosure, always take note of the Run/Safe boxes.

The "Run/Safe" box has the following indicators:

GREEN "Safe" -	Safe for occupancy under normal, "Restricted Access" conditions - Access by trained, authorized personnel
YELLOW "Operational" -	"Controlled Access" Only - Access by special interlock key control only
RED "Unsafe" -	Exclusion Area - No access by personnel under any circumstances

A simple rule to remember regarding the Run/Safe box is:

The box must always indicate SAFE unless:

you have an interlocked access key (used for Controlled Access) - in this case the box can indicate OPERATIONAL/ SAFE.

The box should NEVER indicate UNSAFE while an area is occupied.

If you are in the beam enclosure and the Run/Safe Box status indicator is incorrect for your level of access you should:

1. hit the Red Emergency Stop Button
2. stop work
3. warn others in the vicinity
4. exit the area leaving tools and equipment behind
5. report to the Crew Chief immediately
6. follow Crew Chief instructions carefully

Controlled Area Radiation Monitors (CARMs)

CARMs continually monitor radiation levels around the accelerator facility and provide a readout on the CARM console in the Machine Control Center. Each CARM has a pre-established alarm set point which if exceeded will cause immediate termination of the beam. The CARMs monitor for unusual radiation levels in occupied areas adjacent to the accelerator tunnel.

CARMs are located in key areas at appropriate intervals for a range of operating conditions. In some cases it will be necessary to have the detector(s) of a CARM in your immediate work area. Always check the OSP or TOSP for any such requirements prior to work in service buildings or other areas near the beam enclosure. If a specific location for a CARM probe is required by an Operational Safety Procedure or an RWP, an Assigned Radiation Monitor or a member of the Radiation Control Group will relocate the CARM probe(s). Only an RCG member or ARM is allowed to relocate CARM probes.

If, in your work area, you encounter a CARM in a High Alarm state, you should:

1. stop work
2. warn others in the vicinity
3. exit the area leaving tools and equipment behind
4. call the Crew Chief immediately
5. remain out of the area until the Crew Chief gives permission to return

The High Alarm condition is indicated by an audible alarm and a red light on the CARM control box. This alarm state results in removal of beam permit. (The yellow light indicates a probe failure. The yellow light should also be reported to the Crew Chief, but it does not constitute an emergency.)

DISREGARD FOR RADIOLOGICAL ALARMS

Working in a radiological environment requires more precautionary measures than performing the same job in a non-radiological setting. This premise is especially true if an emergency arises during radiological work.

Radiological emergencies include improper status indicator or change of status indicator on Run/Safe Box, fire in a Radiological Area, high radiation exposure to personnel, injury or loss of life in a Radiological Area, and damage, abuse, or loss of radioactive material or sources.

Responsibility for dealing with an emergency initially rests with the person discovering it. Your responsibility regarding discovery of a radiological emergency includes:

• Taking appropriate action to protect life, then property, then the environment.
  
  
• Warning others in the area of the situation and minimizing your own radiation exposure.
  
  
• Making the appropriate notifications as given below.

11.2.1 Accelerator Emergency

In the event of a radiological emergency which results from accelerator operations, the Crew Chief should be notified at the Machine Control Center (MCC), phone number 7044, 7055, or cellular phone at 804-879-3367. The Accelerator Crew Chief has overall responsibility for safety and coordinating emergency response on the accelerator site.

The following steps should be taken in the event of a potential "beam on" accelerator accident:

1. Stop work or activity in the location of the suspected accident. If in the accelerator tunnel, press the Red Emergency Stop Button on the nearest Run/Safe Box. Make a mental note of your location and exit the area immediately. Warn any others in the area of the situation.
   
   
2. Seek immediate medical attention for any injured individual - dial 911 and request assistance. An injured individual who is not conscious or ambulatory should only be moved by medical personnel. Provide any information you know regarding radiological conditions to the emergency services contact.
   
   
3. Report to the Crew Chief at the MCC and explain what occurred and any actions you've taken. Follow the instructions of the Crew Chief carefully.
   
   
4. The Crew Chief may request that an ARM be allowed to perform a radiation survey on your person or may request that you allow a survey of certain articles from your person. Compliance with the Crew Chief will provide important information regarding potential radiation exposure.
   
   
5. If uninjured, remain at the location designated by the Crew Chief until the Radiation Control Group Staff makes a determination of the extent of potential exposure.

11.2.2 Non-Accelerator Emergency

In the event of a radiological emergency involving spills or loss of radioactive material, potential excessive or unmonitored personnel exposure, or spread of contamination to personnel or uncontrolled areas, the Radiation Control Group (RCG) should be notified.

All security guard posts, the MCC, and the Experimental Hall Counting House have up-to-date emergency call-out lists which can be used to contact the RCG. The inside front cover of the TJNAF telephone directory contains phone numbers of EH&S staff including radiation protection personnel. The RCG also maintains a cellular duty phone - 879-1617.

11.2.2.1 Spills

In the event of a spill or other loss of control of radioactive material, remember the acronym SWIM'N.

S - Stop the spill - for example upright an overturned container that is causing a spill.

W - Warn others - make sure other people in the area know what has happened.

I - Isolate the area - close the doors or use convenient items to form a barrier.

M - Minimize your exposure - once you have taken initial steps, move away from the area.

N - Notify Radiological Control personnel - await RCG personnel at a safe distance.

11.2.3 Calling 911

The 911 emergency number can be reached from any TJNAF phone - there is no need to dial 9 for outside access.

Call 911 to report radiological emergencies only when:

• There are, or could be injuries involved
  
  
• There is a fire
  
  
• Emergency rescue or other similar aid is required

11.2.4 Considerations in Rescue and Recovery Operations

If emergency personnel require access to the accelerator enclosure, it is important that their entry not be delayed. The normal administrative controls that we follow daily are not applicable to emergency situations. For example, if firefighters need access to the enclosure, the beam would be terminated and the accelerator would be placed in a safe condition. At this point, the firefighters would be allowed access. Entry for short periods under these conditions is not expected to result in significant radiation exposure. It is very unlikely that any emergency responder could receive a dose that approaches the TJNAF design goal for Radiation Workers during an emergency entry. Radiological conditions can be determined following the emergency entry in order to calculate doses to the emergency responders.

11.2.5 Emergency Exposure Guidelines

Planned Special Exposures (PSE)

In some cases where a planned event is anticipated to cause personnel to exceed the routine dose limit of 5 rem, and other options are not practicable, a Planned Special Exposure may be necessary. These events are not considered emergencies but are unusual and are not expected to be repeated. The total dose to an individual under these circumstances must not exceed 10 rem, including all other exposure received for the year.

Lifesaving and Rescue Operations

In extremely rare cases, emergency exposure to high levels of radiation may be necessary to mitigate injury, death or major property damage. These operations will be guided by an emergency response director. Careful judgement must be used during such situations of substantial personnel risk.

The DOE emergency guidelines for such personnel, when the lower dose limit of 5 rem is not practicable, are as follows:

- Protecting major property - 10 rem

- Lifesaving or protection of large populations - 25 rem - or greater than 25 rem when:

only volunteers are used



risks are thoroughly assessed



personnel are fully briefed on magnitude of risk