Brigade Order Brigade Order Operations 14 Part 3 Section 1 Title Siemens Electronic Personal Dosimeter Contents No. Purpose 2 Strategic Aims and Objectives 2 Introduction 3 Why do we require Radiation Detection equipment? 3 General Description 3 To Use the EPD 4 Clearing the Memory 4 Recording Doses 5 Changing Display Screen During Use 5 Illuminating the Display Screen 5 Operational Considerations 5 Use in the Mass Decontamination Sector 6 Safety Note 6 Standard Testing, Maintenance and Collaboration 6 Alarms and what they Signify 6 Alarm Activation Procedure 7 Clearing the Alarm from the EPD 7 1 of 8
Low Battery Warning 7 After Operational Use 7 Switching the EPD Off 7 Clearing and General Care of the EPD 8 Roles, Responsibilities and Review The Head of Operations & Risk is responsible for ensuring this Order is implemented across the Service. Level 1/2 Incident Commanders or a Sector Commander Mass Decontamination at a major incident will ensure the day to day operation of this order The Head of Operations & Risk will review this Order when new legislation arises or as and when organisational needs require. Brigade Order Operations 14 Part 3, Section 1 Use of the Siemens Electronic Personal Dosimeter Purpose This Order provides guidance on the occasions when the Siemens Electronic Personal Dosimeter should be used as well as detailing how to operate, test and maintain the operational readiness of the equipment. Strategic Aims and Objectives This Order supports: Strategic Aim No 3 Secure the highest level of safety and welfare for all staff by providing effective supervision, training and safe systems of work 2 of 8
Introduction Incident Response Units (IRU) and certain other items of ancillary equipment were provided to the UK FRS by the Dimension project following the terrorist attack on the World Trade Centre in 2001. According to intelligence sources the greatest perceived threat at this time was that the United Kingdom was at risk from a Chemical, Biological, Radiological or Nuclear (CBRN) attack. The IRU s and ancillary equipment were provided to assist the FRS with the large scale decontamination of members of the public in conjunction with the Department of Health. The Rados 200 Survey meter is the equipment provided to assist the FRS with the detection of the presence of certain types of radioactive material. 42 Siemens Electronic Personal Dosimeters are carried on the IRU but as of April 2010 all SFRS wholetime fire appliances, the Incident Command vehicle, the 6 RDS appliances based at OS, NP, LU, BN, MD and WH which support an out of county IRU deployment and the 3 RDS appliances at SY, WL and TW will all carry 2 Electronic Personal Dosimeters. These 30 additional dosimeters were given to SFRS by the Communities and Local Government Department and are housed in a protective yellow Peli case which also contains one Rados 200 Survey meter (See Brigade Order Operations14 Part 3 Section 2 Rados 200 Survey Meter). Why do we require Radiation Detection Equipment? To facilitate the determination of cordons in the early stages of an incident. To provide continued monitoring of the extent of the inner cordon during FRS operations. Information gleaned from the meter will assist in the development of the Incident Commanders Dynamic Risk Assessment and Operational plan. It allows for contingency measures to be put in place should readings above normal background levels be detected. The Siemens Electronic Personal Dosimeter (EPD) has two primary functions: To alert the wearer to the presence of potentially harmful levels of ionising radiation. To provide data for forensic evidence which can be used in any subsequent enquiry or legal proceedings. General Description The EPD is a compact unit with a Liquid Crystal Display (LCD). It is battery operated and simultaneously measures and displays dose rate and absorbed dose of gamma or beta radiation with an inbuilt sounder unit to activate audible warning alarms. The unit will not measure alpha particles or neutron emissions. The EPD has a plastic casing and should not be immersed in water nor is it intrinsically safe and the EPD s use in a potentially flammable atmosphere should be subject to a Dynamic Risk Assessment (DRA). The EPD does offer good Radio Frequency Immunity (RFI) and should not be adversely affected by the use of fire ground radios. Main unit features 3 of 8
To Use the EPD Turn battery compartment cover counter clockwise Insert 1 x AA alkaline batteries (Positive + terminal first) Replace battery compartment cover Press operating button The EPD microprocessor will automatically record the date and exact time of battery loading. The EPD will switch on when the battery is inserted or can be switched on by pressing the operating button until the default screen is displayed. When switched on the EPD will automatically display the list screen. The test screen will be displayed for approximately 12 seconds, the warning sounder and the LED will operate. The EPD will then either show OFF or revert to the default screen. If OFF is displayed press and hold the operating button to switch the unit on. the default screen will then be displayed. Clearing the Memory Prior to operational use, after switching on, the default screen must be cleared of any accumulated dose from its last known state. Press and hold the operating button until the symbol CLr? Is displayed Press the operating button twice and the symbol CLr? will begin to flash Press the operating button twice again and the display screen will reset to the current conditions. 4 of 8
Recording Doses EPD Personal Absorbed Accumulated Dose readings should be recorded using the reverse of the relevant Personal Protective Equipment/Respiratory Protective Equipment tallies prior to entry and upon exit from the hazard area. A permanent record should also be made on form FB72 and this should be kept on the employees Personnel file indefinitely. Changing Display Screen During Use The default display screen shows the Personal Absorbed Accumulated Dose of the wearer in either microsieverts (µsv) or millisieverts (MSv). The flashing heart symbol in the top right corner indicates that the EPD is working correctly. To display the Personal Dose Rate, depress the operating button twice quickly and this then will display in microsieverts per hour or millisieverts per hour. This screen will revert back to the default screen after approximately 12 seconds. The main difference between the two screens is: Personal Dose Rate measures the speed at which the dose is being absorbed and this means that the microsieverts (µsv/h) or millisieverts (MSv/h) are measured by time and the symbols changes to reflect this. Illuminating the Display Screen To illuminate the display press the operating button once quickly and the screen will illuminate for approximately 10-20 seconds and then fade automatically. Personal Dose Rate v. Personal Absorbed Accumulated Dose Personal Dose Rate: equates to the speed at which the radiation is accumulated. The EPD can measure Personal Dose Rate in either microsieverts per hour or millisieverts per hour switching automatically between the two, depending on the magnitude of the recorded dose. Personal Absorbed Accumulated Dose: equates to the total amount of radiation accumulated. The default display shows Personal Absorbed Accumulated Dose in Microsieverts or millisieverts switching automatically between the two depending on the magnitude of the recorded dose. Operational Considerations The EPD s may be used by personnel deployed into potentially hazardous environments where radiation may be present. The deployment and use of this equipment will be carried out on the instruction of the Incident Commander based on the outcome of a Dynamic Risk Assessment (DRA). The DRA will determine the required level of PPE and RPE, the number of personnel required to complete the required tasks, the nature and availability of decontamination facilities and the operational urgency of the situation. The EPD s should be worn on the inside of the required level of PPE. 5 of 8
The use of the EPD s supplied by the Fire Resilience Directorate (FRD) through the Department of Communities and Local Government should comply with each Fire and Rescue Service (FRS) individual operational procedures for radiation incidents. Use in the Mass Decontamination Sector Whenever EPD s are to be used in the Mass Decontamination (MD) sector the DRA will assist in the development of an operational plan which should be communicated to all relevant personnel before commencing Mass Decontamination operations. This plan must consider the action to be taken if the MD sector should be exposed to radiological contamination or irradiation implementing a safe system of work, commensurate with the radiation levels indicated, or closing down and relocating the MD sector if necessary. Safety Note The EPD is not intrinsically safe and use in a potentially flammable atmosphere should only be carried out following a full DRA. Any contaminated equipment should be left inside the Inner Cordon in a designated area in preparation for specialist analysis. Standard Testing, Maintenance and Calibration The EPD should be standard tested on acceptance, before and after operational use and quarterly. The recorded use, maintenance and testing of this equipment should be recorded on the standard test record. All defects must be reported to Fire Control and the defective EPD returned to Technical; Services immediately. Alarms and What they Signify The EPD has three main alarms: Initial Dose Rate Alarm This activates at 100 microsieverts (µsv/h) and is an intermittent double fast tone lasting 20 seconds. The LED on top of the unit will flash slowly and will reset itself when the dose rate falls below 90µSv/h. Dose Constraint Alarm This activates at 5 millisieverts (MSv) and is a continuous double speed tone and a rapid LED flash. When the alarm is activated the symbol 10/h will be indicated on the LCD display screen underlined in the top left hand corner. Exceptional Dose Alarm This activates at 100 millisieverts (MSv) and is a continuous single tone and a rapid LED flash. When the alarm is activated 10/h will be indicated on the LCD display screen underlined in the top left hand corner. Alarm Activation Procedure 6 of 8
When the EPD audible and visual alarm actuates the following procedures are to be adopted: STOP all activities Carry out a further DRA Contact BAECO or Sector Commander via radio to advise of activation. Retrace your steps until alarm ceases. Establish Inner Cordon in alarm free area. Identify the alarm type. Follow instructions given by BAECO and/or Sector Commander Clearing the Alarm from the EPD None of the alarms can be reset by the wearer but the Initial Dose Rate Alarm will reset itself when the dose rate falls below 90µSv/h microsieverts per hour. An EPD reader will be required to clear the Dose Constraint Alarm and the Exceptional Dose Alarm. Upon activation of either the Dose Constraint Alarm or Exceptional Dose Alarm is activated at an incident the EPD must be returned to Technical Services where collection by the relevant contractor for resetting will be arranged. If the unit is suspected of being contaminated such as being worn on the outside of PPE, the EPD must remain at the scene within the Inner Cordon at an identifiable location for later decontamination. Low Battery Warning The EPD will display a warning symbol of a constant black battery in the bottom left hand corner of the LCD display screen indicating that a minimum of 10 hours battery life remain. One charged AA battery should give 200 hours use. After Operational Use All EPD Personal Absorbed Accumulated Dose readings should be recorded upon exit from the hazard area, using the reverse of the relevant PPE/RPE tallies and a permanent record should be kept on form FB 72. The display screen must be cleared of any accumulated dose prior to switching off. Switching the EPD Off After the EPD has been cleared of any accumulated dose, the EPD should be switched off. The EPD stores chronological information that may be interrogated by an EPD reader in the event of a Radiation incident. To switch the EPD off: From the default screen hold the operating button until On is displayed and release the button. Press the operating button twice and OFF will flash. Press the operating button twice again and the display screen will indicate OFF. This OFF will remain on the screen to indicate the status of the EPD. 7 of 8
Cleaning and General Care of the EPD The EPD should be cleaned with a moist cloth and warm soapy water using neutral water based detergent. The EPD is only splash proof and under no circumstances should the unit be immersed in water or liquid. After cleaning, dry with a soft cloth and shake or blow any excess water from the sounder aperture. 8 of 8