GIF++ ACCESS SYSTEM

Dorothea PfeifferGIF++ Project Meeting16.01.2013

Thanks to: V. Martins De Sousa Dos Rios, D. Vaxelaire, D. Haasler

2

GIF++ facility in EHN1

16.01.2013

Part Details

Gas area Hosts large part of the peripheral infrastructure and services (gas supplies and systems)

Preparation area

Area for detector preparation directly accessible from control room

Bunker (will replace present zone 154)

Contains 16.65 TBq Cs-137 source (662 keV gammas) and muon beam

Control room

Two separate control rooms for services and users in barracks R-B84 and R-A81 with direct access to the preparation area

Dorothea Pfeiffer

GIF++ in Secondary Beams Area, but due to presence of 16.65 TBq source and muon beam more dangerous than

other installations

3

General Requirements

Dorothea Pfeiffer

Personal access device: PAD People must be able to enter and leave the zone

(very frequently: at times every few minutes) Material access device: MAD

Large and heavy detectors must be brought into and removed from the zone by opening the roof or large concrete door (rarely, a few times per month)

Tools and other material must be brought into and out of the zone (several times per week)

16.01.2013

4

RP Access System Requirements (EDMS Document 1233302)

Dorothea Pfeiffer

Source/beam interface requirements (details of source interface needed): Access must not be possible if the source (or the beam) is

operational Operation of the source (and the beam) must be inhibited and

it must be in its parking position if the PAD or the MAD is open or any shielding is removed (if any equipment interlocked with the source loses its SAFE condition, the source has to be sent to it parking position and then inhibited)

Access must be inhibited if radiation levels inside the zone are above a defined threshold which is determined by an interlocked RP monitor inside the irradiation cave

(Comments by me in blue)

16.01.2013

5

RP Access System Requirements

Dorothea Pfeiffer

Specific requirements for persons Controlled entry and exit of each person via a

personnel access device (PAD) which excludes the access of more than one person using only a single access token

Entry and exit granted only allowed after badging with a DIS dosimeter. Given the significant hazard posed by the source activity specific access rights might be of advantage to ensure that intervening personnel is aware of the specific hazard

16.01.2013

6

Proposed Solution

PPG, Roof: If opened, patrol lost

PPE & Turnstile: Access rights of people checked, key released and people counted

PPE 2: Key that was taken at turnstile has to be used in key access mode (patrol not lost)

MAD: access for material up to PC size

16.01.2013Dorothea Pfeiffer

Personal Protection Exit

Personal Protection Gate

Personal Protection Entry

PPE & Turnstile

GIF++ Zone

Pre Zone

MAD

PPE 2

Small material access

7

Detailed access procedure

Dorothea Pfeiffer

Access without breaking the patrol Precondition: Zone is patrolled (number of people in zone = 0) User presents his DIS dosimeter in front of the PPE & turnstile,

gets a key from the key distributer, If permission to access is given, the key has to be turned to

unlock the turnstile to enter At the PPE 2 behind the turnstile the key taken before has to be

used in key access mode (like this one avoids that the key is turned at the turnstile, but then left behind so that a second person could enter using the same key)

The turnstile increments the number of users in the zone by one (the information who entered will be written to a database)

To leave the zone the person will badge again, put the key back and the name will be erased from the database

16.01.2013

8

Open questions

Dorothea Pfeiffer

If the PPX, PPG or roof is opened, the turnstile/database combination cannot control the number of persons in the zone anymore (people could enter/leave via PPX or PPG) Patrol carried out before closing PPG or roof deletes old data

from database?Þ The database is not considered to be a device for

safety, only for users access control Possible to open PPE by turning the key, but then leaving it

there (in this case the next person could enter the turnstile but not take the key and subsequently use the key the first person left in the PPE)?

How can (accidental) removal of shielding block or opening of roof be detected? Special locking elements exist, only when veto in CCC is set moving of blocks possible.

16.01.2013