Object ID: 00000018WIA308CA770GYZ
Topic ID: id_40024178 Version: 1.14
Date: Jul 26, 2022 1:12:05 PM

Security Zone

The security zone is the magnet room and the walls of the magnet room.

Table 1. Image legend
Number	Description
1	Magnet room
2	Room length = 19.1 feet (5.8 m)
3	Room width = 12.1 feet (3.7 m)

Static magnetic field plots for siting (rule of thumb - assumes no ferromagnetic materials) may be found at:

https://www.gehealthcare.com/support/site-planning

Note: The figure above states the approximate minimum room size for your MR system. Consult your GE system pre-installation manual for specific dimensions of your system and additional magnetic field plot information.

Important: You need to understand the meanings of ferromagnetic and ferrous substances or items:

A substance that is ferromagnetic has a large positive magnetic susceptibility. (Example: Iron.)
An item that is ferrous can posses intrinsic magnetic fields and react strongly in an applied magnetic field. (Examples: Iron, nickel, and cobalt.)

Note: The attractive force of the magnetic field in the Security Zone can cause ferromagnetic items to become projectiles and contraindicated biomedical implants to fail. In short, ferromagnetic items and contraindicated biomedical implants are NOT allowed in the Security Zone. The MR System operates with a highly sensitive RF receiving front end to be able to capture the signal of an object scanned. The Magnet Room part of the MR System installation provides the RF isolation to reduce the interference from electrical devices outside the shielded location. It is possible that any device that functions with active electronic circuitry may potentially interfere the operation of the MR System if such device is introduced inside the Magnet Room even though the device does not have an intentional RF Transmitter. Extreme EMC measures must be taken into account in the design and manufacturing of an electrical device if such device is intended to operate inside the Magnet Room. A device that may potentially interfere the MR System if introduced inside the Magnet Room are those containing active electronics. Some examples include: Switching Mode Power Supply (SMPS), microprocessor, Digital Signal Processors, analog to digital converters, LCD displays, keypad controllers, motors, battery operated devices.

Warning

The Security Zone warning sign must be posted on the entrance to the magnet room to alert personnel to the high magnetic field and warn not to bring ferromagnetic objects into the magnet room.

Warning

Ensure that the Security Zone complies with your local statutory requirements.

Security Zone warning sign

The Security Zone warning sign alerts personnel and patients of the following:

Strong magnetic field
Hearing protection: During a scan, all persons in the scan room are required to wear hearing protection to avoid possible hearing impairment.
No pacemakers*
No neurostimulators*
No conductive/metallic implants*
- Persons with pacemakers, neurostimulators or metallic implants must not enter this area. Serious injury may result.
No loose metal objects: Iron, steel and other ferrous material must not be taken into this area. Serious injury or property damage may result.
Risk of non-ionizing radiation: If a scan is performed with the magnet room open.

*In general, patients with conductive (e.g. metallic) implants are contraindicated for MR scans. Some implantable devices have been labeled as MR Conditional under certain operating conditions. Only use quadrature transmit for MR Conditional devices. MR Safe implants will have the MR Safe symbol in their implant documentation.

When evaluating whether to proceed with MR scanning on patients with such implants, consult the implantable device’s labeling.

Figure 2. Security Zone warning sign 201.7.9.2.101 (d)

Note: Your system may have a slight variation of this sign.