Radiation safety for supervised areas
The training below is required for unaccompanied access to accelerator areas and beamline hutches (controlled areas). It is an extension to the radiation safety training for supervised areas. Note that unaccompanied access to controlled areas is only allowed for workers who are assigned tasks that require access to controlled areas.
1. Access to accelerator areas
Accelerator areas constitute controlled areas where radiation levels may be significant. There are four main accelerator areas at MAX IV: the linac tunnel, the short pulse facility (SPF), the 1.5 GeV ring tunnel and the 3 GeV ring tunnel. In addition, there are two smaller accelerator areas used for test and development purposes: the gun test room and the cavity test room.
All entry points, including concrete doors, leading to an accelerator area are marked “Kontrollerat område” (controlled area). They are equipped with switches that turn off the source of the ionizing radiation should the door be opened during operation. Doors to accelerator areas are locked and an access card is required to unlock them. This only works if the radiation source is off. The access card will not unlock the corresponding door if the radiation source is on. The radiation hazard status and access status is indicated by lights above both regular and concrete doors.
The door is unlocked by swiping the access card at the tag reader marked “IN”. If several persons enter at the same time, each person must log in separately by swiping their access card. During visits, it is sufficient if the person responsible for the group logs in.
Instructions are posted at the entrances to the accelerator areas describing how to enter and under what conditions entry is allowed. These instructions must be studied before entry.
The picture above shows the entrance at the start of the linac tunnel. Access is only allowed if the green light above the door is lit. The orange light flashes when a search procedure in the area behind the door is in progress and is lit when the search is complete. The red light indicates that a radiation hazard is present in the area behind the door.
In addition, lasers are utilized in some areas, such as the linac tunnel. The blue light above the door is lit when a laser hazard is present in the area behind the door.
The doors are not locked from the inside, so exiting is always possible. In the event of an emergency, it is always possible to open the door from the outside by breaking the plastic cover and using the emergency thumb turn. The accelerators will turn off as soon as the door is opened, as the red switch is connected to the personnel safety system and detects that the door is not closed.