IKN-RS-SOP-09: Area Classification

DOCUMENT NO. : IKN-RS-SOP-09

INTRODUCTION

The risk to any person working with unsealed radioactive materials should be assessed before the work commences and should be kept under review. This will require an assessment as to whether a particular area needs to be designated as a ‘controlled area’ or as a ‘supervised area’. The risks associated with each controlled area need to be assessed and control measures to restrict exposure documented.

PURPOSE

Designated Areas are a legal requirement and to comply with the Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations 2010 when working with radioactive material. The purpose of this Standard Operating Procedure (SOP) is to manage the radiation risk by identifying and segregating higher risk activities from the lower, and thus controlling the extent of radiation exposure.

RESPONSILIBILITY

Radiation Protection Officer (RPO)
Radiation Workers

Frequency

Not Applicable (N/A)

Equipment

Calibrated Survey Meter – Direct survey using Survey Meter
Classification using Inverse Square Law Equation
Extrnal Dosimeter Result – Film Badge, TLD Badge and TLD Ring

PROCEDURE

Determining Designated Areas

Area where the annual dose received by a worker is likely to exceed three-tenth of the dose limit shall be classified as a controlled area as refer to Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations 2010 document.
Controlled Area means any area in which specific protection measures and safety provisions are required for controlling normal exposures or preventing the spread of contamination during normal working conditions, and preventing or limiting the extent of potential exposures. The following areas have been designated as controlled areas:
1. Nuclear Medicine
  - Radioactive Storage Room
  - Radioactive Waste Room
  - Radionuclide Ward
  - Cyclotron
  - Decay Tank
  - Radiopharmaceutical Preparation Room
  - QC Room
  - Hot Lab
2. Radiology
  - CT Scanner Room
  - Angiography Room
  - General Radiography Room 1
  - General Radiography Room 2
3. Radiotherapy and Oncology
  - Linac 1 treatment room
  - Linac 2 treatment room
  - Novalis treatment room
  - CT Simulator room 1
  - CT Simulator room 2
  - Brachytherapy OT
  - Tomotherapy treatment room
  - Radioactive waste room
  - Radioactive preparation room
  - Radioactive store room
A Supervised Area is one where either person might receive more than one-tenth of the relevant annual dose limit, or the conditions of the area need to be kept under review to determine whether it could become a Controlled Area. The following areas have been designated as controlled areas:
1. Nuclear Medicine
  - Waiting Room
  - Radioiodine Preparation Room
  - Injection Room
  - Gamma Camera Room
  - Gamma Camera /SPECT-CT Room/PET-CT Room
2. Radiology
  - CT Scanner Room Control Room
  - Angiography Room Control Room
  - General Radiography Room 1 Control Room
  - General Radiography Room 2 Control Room
3. Radiotherapy and Oncology
  - Linac 1 treatment console area
  - Linac 2 treatent console area
  - Novalis treatment console area
  - Tomotherapy treatment console area
  - CT Simulator 1 treatmet console area
  - CT Simulator 2 treatmet console area
  - CT Simulator 1 changing room
  - CT Simulator 2 changing room
  - Brachytherapy treatment console area
A Clean Area referred to the received dose of less than one-tenth of the relevant annual dose limit, or the conditions of the area need to be kept under review to determine whether it could become a Supervise Area.
The following areas have been designated as clean areas at all times.
1. Nuclear Medicine
  - Nuclear Medicine Office
  - Nuclear Medicine Reception Counter
2. Radiology
  - Radiology reception counter
  - Radiology office
3. Radiotherapy and Oncology
  - Radiotherapy reception counter
  - Radiotherapy office
RPO shall ensure that supervised and controlled areas are clearly demarcated and appropriate legible notices and warning signs bearing the radiation symbol as shown in the Figure 1 are posted conspicuously in strategic places.

Administrative Procedures in Supervised Area and Controlled Area

The controlled area sign must be displayed at the door and must include an indication of the radionuclide whether it is in the form of a sealed or unsealed source.
In transit, access to the area around a lead trolley or lead pot containing radioactive sources is also controlled. The trolley containing radioactive sources will be the responsibility of the Radiation Workers whilst it is in transit and it is their responsibility to ensure that other people do not pass within 0.5 m of the trolley.
No person shall enter a controlled area unless he has been assigned to the area or has been authorized by the RPO to enter the area.
Visitors should be accompanied by a radiation worker into a radiation area.
RPO shall periodically review the conditions to determine the possible need to revise the protection measures and safety provisions and the boundaries of the supervised and controlled areas.
The area determination shall be performed by using passive external dosimeter such as OSL or TLD to be exposed located in the selected area or room for the minimum of three consecutive months.

REFERENCES

Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations 2010.
Nuclear Medicine Resource Manual, IAEA 2006.
Radiation Protection in Nuclear Medicine, Radiation Protection Series Publication No. 14.2, ARPANSA 2008.
Applying Radiation Safety Standards In Nuclear Medicine, Safety Reports Series No. 40 IAEA 2005.

DISCLAIMER

This Standard Operating Procedure (SOP) was developed based on compilation of best available information, knowledge, field experience, and general practices to provide guidance to IKN staff in performing the activities defined herein, in a consistent and standardised manner.
IKN does not guarantee nor accept any legal liability whatsoever arising from or connected to the accuracy, reliability, currency or completeness of any material contained herein.
IKN shall take no responsibility for and will not be held liable for this document being temporarily unavailable due to technical issues beyond our power and control.