Radiological Equipment - Basic

Objectives

• For each radiation detection instrument:− Identify capabilities, limitations, and primary uses− Identify the components, controls, and indicators− Perform basic operating procedures− Understand operator maintenance

IsoTrak DoseGuard

Personal Alarm Dosimeter

Personal Dosimeter

• Capabilities− Records total gamma/x-ray dose and dose rate− User-adjustable features

• Limitations− Not intended for survey− Does not detect alpha, beta, neutrons− No display light

• Best use− Alert wearer of high dose or dose rate− Indoors hospital staff

Equipment Safety Precautions

• Fragile instrument; might survive 1 meter drop• Do not submerse; can withstand rain

Components, Controls, and Indicators

8.8.8 mR- +

Speaker

Clip

Button

Display

Chirp icon

Battery icon

Autoranging 3-digit Unit of measure

Battery well

Prepare for Operation

• Before-operation checks− Look for obvious damage

• Install battery: 1 AAA − Positive terminal inside

• Power up− Hold button until long beep, then release− Automatic power up when installing battery

• Check dose reading is 0.0 mR

Basic Operating Procedure

• Default is total dose• Check dose rate reading

− Press button 1x− Display shows dose rate for 10 sec., returns

to default

Types of Alarms

• High radiation− Dose alarm− Dose rate alarm

• Equipment fault− Overflow alarms− Battery alarms

Dose or Rate Alarms

• Alarm sounds when exceeding alarm set point− Dose alarm: display flash + 1 beep/sec. − Dose rate alarm: display flash + 4 beeps/sec. − Both: display flash + 4 beeps/sec.

Dose or Rate Alarms (cont.)

• To silence audible alarm: press button 1x• To reset alarm

− Dose rate alarm stops when exposure is reduced− Dose alarm stops when dose is reset to zero

Overflow Alarms

• Occurs when meter exposure exceeds factory-set measurement upper level

− Dose overflow (1000 R): display “doo” + 2 beeps/sec. − Rate overflow (300 R/h): display “dro” + 8 beeps/sec.

• Cannot be reset until removed from exposure

Battery Alarms

• Alarm during startup− Low battery: display shows battery symbol− Dead battery: failure to start

• Alarm during operation− Low battery: battery symbol flashes, 1 long beep/hour− Dying battery: display “Lob” and 1 beep/sec.

• Measurement functions stop

Respond to Alarms

Type of Alarm• Dose/rate alarm

• Overflow alarm

• Low battery alarm

Required Action• Take immediate action to

reduce exposure • Silence and reset alarm

• Shut down instrument, remove from area

• Change battery

Equipment Application

• Need for dosimetry− Personal exposure record− Alert user of high dose or dose rate

• Wear on chest pocket− Instrument inside pocket – prevent dropping− Remove metal objects from pocket – avoid

unintentional shielding− Place in plastic bag (optional)

After Operating

• Power down procedure− Press button 2x− Display reads “OFF”− Hold button until long beep, release

• Perform after-operation maintenance• Storage

− Remove battery− Store in box with instructions

Operator Care and Cleaning

• Wipe exterior surfaces clean• Do not submerse; rain resistant but not water

tight− If submersed—open battery well, shake out excess

water, let it air dry

• Avoid harsh solvents—may damage plastic case

Change Battery During Operation

• Replace battery if low battery alarm• Power Off; change battery; power On

− Dose reading and settings not lost

IsoTrak DoseGuard Summary

• Understand capabilities, limitations, uses• Recognize components, controls, indicators• Perform basic operation• Understand operator maintenance

Ultra Radiac

Personal Radiation Monitor

Radiation Monitor

• Capabilities− Measures and records gamma/x-ray dose and rate− Multiple user features, data logger, PC download

• Limitations− Does not detect alpha, beta, neutrons

• Best uses− Personal dosimeter and rate meter− Used by decon team outdoors

Equipment Safety Precautions

• Do not submerse, but can withstand decon operations

Controls and Indicators

Digital Display

Status indicators

Autoranging digital display

Units of measure

Function Keys

• Rate and Dose keys: Display dose rate or dose• Alarm key: Display “stay time” in minutes• Light key: Power On backlight• Clear/Test key: Perform operational test• On/Off key: Power On and Off

Keys have other functions for advanced users

Battery Life Indicator

• Low battery: Flashing “BAT” in upper left corner− Less than 10 hours left− Press Clear/Test key to display minutes of battery left

• Dying battery: Flashing “b” on blank display− Normal operation stopped

Prepare for Operation

• Before-operation checks− Look for obvious damage

• Install batteries: 4 AAA− Observe polarity indicator− Starts “sleep” mode

• Power up− Press On/Off key

Prepare for Operation (cont.)

• Perform operational test− Hold Clear/Test key until “888” appears− Test alarm: Press Rate, Dose, or Alarm keys− After self-test: Flashing “9” = pass or “0” = fail − Press Clear/Test key

• Check the dose is 0.00

Attach Carry Case

Basic Operating Procedures

• Check dose and dose rate• Turn on back light• Check stay time• Data logging• Alarms

Check Dose and Dose Rate

• Current dose rate− Normal default reading− Press Rate key from dose display

• Total dose− Press Dose key− Returns to rate after 10 sec.

Backlight

• Press Light key− Blue light for 10 sec.

• Why can’t I see the light?

Check Stay Time

• Stay time = number of minutes to safely remain at current dose rate and not sound dose alarm

− Based on current dose rate and dose alarm setting

• Press Alarm button− Normal background = “999”− If rate increases with low dose alarm set point, stay

time decreases

Data Logging

• Log data point at:− Any dose alarm− End of normal shift

• Records up to 300 events− Records date, time, dose, rate, etc.

• Logging a data point− Power On, rate displayed− Hold Rate + Dose keys until number

stops flashing− New number = log sequence

Alarms

Type Alarm Visual(flashing)

Audible(if enabled)

Vibration(if enabled)

High rate Entire display,

Left LED red

Beep quickly Vibrate

Low rate Rate and Alarm indicators,

Left LED green

Beep slowly Vibrate

High dose Dose and Alarm indicators,

Right LED red

Beep quickly Vibrate

Low dose Dose indicator,

Right LED green

Beep slowly Vibrate

Resetting Alarms

• High rate alarms− Press Clear/Test key to still vibration alarm− Back away to stop audible and display alarms

• Low rate alarms− Press Clear/Test key to still audible/vibration alarms− Back away until display alarm stops

• Dose alarms− Press Clear/Test key to still audible/vibration alarms− Log the data point

Respond to Alarms

Type of Alarm• High dose/rate alarm

• Low dose/rate alarm

• Low battery alarm

Required Action • Take immediate action to

reduce exposure • Silence and reset alarm

• Warn others of increased exposure

• Silence and reset alarm

• Change batteries

Equipment Application

• Decon line use− Personal exposure record− Alert user of high dose or dose rate− Use “source finder” mode as survey meter

• Wear on belt− Instrument upside down,

face out – flip up to read

After Operating

• Power down− Hold On/Off key until display shows “OFF”

then “- - -”

• Perform after-operation maintenance• Storage

− Remove batteries− Store in carry case− Store IR reader with RSO

Operator Care and Cleaning

• Wipe exterior surfaces clean• Do not submerse—not water tight• Avoid harsh solvents—may damage

plastic case

Change Batteries

• Replace batteries if low battery alarm• Power Off; change batteries; power On

− Ensure correct orientation− Dose reading and settings not lost

• Sleep mode starts automatically− Power On then Off to prevent

battery drain

Ultra Radiac Summary

• Understand capabilities, limitations, uses• Recognize components, controls, indicators• Perform basic operation• Understand operator maintenance

Radiation Survey Meter

Responder kit and equipment

Survey Meter Kit

• Capabilities− Measures alpha, beta, gamma, x-ray dose rate− Complete kit in hard case

• Limitations− Requires separate probes− No dosimeter function

• Best uses− Area survey− Check radiation from contaminated person/object

Equipment Safety Precautions

• Imbedded radioactive check source—keep covered

− 1 μCi Cs-137 on side of case

• Delicate pancake probe face, internal components; do not drop or puncture

• High internal voltage; power Off before changing probes or opening case

Major Components

Hard carry case

Meter

Cable

Pancake probe

Batteries

Gamma probe

Additional Components

• Additional survey meter• Cable• Extension handle pancake probe

Controls and Indicators

DET DET 1 2

RESET

LIGHT

AUD

ON

OFF

F

SOFF RATEMETER

SCALAR

CAL

Battery well

Calibration switch well

Probe connector

DisplayF/S toggle (response time)

Audio toggle (chirp)

Detector toggle (parameters)

Light button

Reset button

Power/mode switch

Digital Display

Status messages

6-digit number (1st & 2nd digits)

Units of measure 4-digit number

Low battery icon

Autoranging decimal and units

Prepare for Operation

• Before-operation checks• Install batteries – 2 D cells

− Observe polarity indicator

• Attach probe− Depends on intended use

Visually Inspect for Damage

Inspection Point – • Instrument exterior• Radioactive source• Instrument display face• Instrument switches• Electrical connectors (all)• Battery well• Electrical cord• Probe exterior• Pancake probe face

Do not use (until fixed) if –• Cracked, broken open• Broken open, loose (missing?)• Cracked, broken open• Will not move• Cannot connect cord• Contacts corroded, lid won’t close• Frayed, torn open• Cracked, broken open• Punctured, torn

Prepare for Operation (cont.)

• Set toggle switches for operating mode− Audio on/off, F/S, Detector 1/2

• Power On: Set Mode switch to Ratemeter− Display shows background reading

• Check operation with check source

Inspect For Proper Operation

Inspection points – • Display reads correctly

• Detector switch set for probe used

• Reset button clears reading

• Light button lights backlight

• AUD toggle ON (chirps) and OFF (mute)

• F/S toggle – no functional test

Do not use (troubleshoot) if –• Display blank or does not show

correct data• Switch cannot be moved or

parameters do not change• Display does not reset to zero

before increasing to normal reading

• (Can be used without light)

• (Can be used without chirp)

• (Can be used in either position)

Basic Operating Procedures

• Use clicker• Use gamma probe• Change probes• Use pancake probe• Alarms

Use Clicker

• Clicker sounds as dose rate increases• Enable using AUD toggle switch

− Disable to mute audible alarm

Use Gamma Probe

• Setup− Attach gamma probe− Set toggle to DET 2− Set mode switch to Ratemeter

• Use to search for gamma/x-ray radiation− Display reads radiation level in uR/h to R/h− Very sensitive to low level radiation− Fast clicker rate

Change Probes

• Procedure− Power Off− Change probe− Set detector toggle switch− Power On

Use Pancake Probe

• Setup− Attach pancake probe or extension handle probe− Set toggles to DET 1, Fast mode (F)− Set mode switch to Ratemeter− Remove protective cover

• Use to search for surface contamination− Display reads in cpm or kcpm (1000 counts/min)− Typical equivalent of ~3300 cpm per mR/h

Respond to Alarms

Type of Alarm• Dose rate alarm -or-

Overflow alarm -or- Overload alarm

• Low battery icon

Required Action • Take immediate action to

reduce exposure • Press reset button

• Change batteries

Dose Rate Alarm

• Alarm sounds when exceeding preset level− Audible continuous sound; “ALARM” is displayed − Alarm is latched; must be acknowledged

• To acknowledge: Press Reset 1x• To reset alarm: Press Reset 2x

Dose Rate Alert

• Alert shown when exceeding preset level− Lower setting than Alarm level− “ALERT” is displayed− Alert is latched; must be acknowledged

• To acknowledge: Press Reset 1x• To reset if alarming: Press Reset 2x

Overflow Alarms

• Overflow alarm: exceeded 100,000 counts− “OFLOW” is displayed− Remove probe from area, press Reset button

• Overload alarm: radiation level above measurement capability

− “OVERLOAD” is displayed− Back out of area− Reset: Press Reset button 2x

Equipment Application

• Area survey− Use gamma probe− Area survey techniques

• Frisk for contamination− Use pancake probe− Search techniques

Area Survey Procedures

• Use clicker for early warning• Enter area slowly

− Hold probe waist high in front− Move probe side to side toward suspicious

areas

• Where to look− Walkways – material tracked in or out− Suspect materials spilled− Items touched by contaminated hands/gloves

Personal Search Procedures

• Clicker off to avoid panic• Check ambulatory person

− Hands− Head and shoulders− Shoes

• Check nonambulatory person− Hands and head− Both sides, shoulders to feet

Materiel Search Procedures

• Equipment or objects− Handle− Bottom or other touched surface− Parts that extend from main object

• Patients’ belongings− Bag items first− Hold bag and check both sides (gamma/x-ray)− Save for more thorough search later

Quick Vehicle Search

• Look at YOUR vehicles• Driver/passenger area (contaminated person)

− Floor and pedals− Items touched (steering wheel, door handles,

radio, etc.)− Seats less likely

• Exterior− Wheel well top inside (dust from below)− Windowsills/wiper wells (dust from above)

After Operating

• Power down• After-operation maintenance• Short term storage

− Disconnect and store in case− Batteries in vs. out

• Long term storage− Remove batteries, obtain new ones− Track calibration due date

Operator Care

• Before operation checks− Visually inspect for damage− Verify proper operation upon power-up

• After operation checks− Visually inspect for damage (same criteria)− Clean or decontaminate

Cleaning Procedures

• Wipe exterior surfaces clean− Use care not to puncture pancake probe face

• Do not submerse—rain resistant but not water tight

− If submersed—open battery well and instrument case, shake out excess water, air dry

• Avoid solvents that could damage polyurethane paint

Survey Meter Summary

• Recognize capabilities, limitations, uses• Recognize components, controls, indicators• Perform basic operating procedures• Understand operator maintenance

Area Radiation Monitor

Area Monitor

• Capabilities− Measures gamma and x-ray dose rate− Wall mounted, 110 V − Internal and external alarm units

• Limitations− Does not detect beta, alpha, or neutrons− No dosimeter function− One hard wired remote per monitor

• Best use− Fixed site monitor

Equipment Safety Precautions

• High internal voltage; power Off and unplug before any service

• Fragile internal components; do not drop• Indoors or fair weather use only

Major Components

Model 272 remote alarm Model 375-10 Digital Area Monitor

Controls and Indicators

Status LEDs

Digital display

Adjustment buttons

Calibration controls

Controls and Indicators (cont.)

Alarm

RS-232 port

110 V AC

Power switch

Relay

Detector center point

Ethernet

Left Side Right Side

Controls and Indicators (cont.)

Alarm

Toggle switches

Analog monitor

Status LEDs

Reset button

RS 232 port

Prepare for Operation

• Inspect for damage• Check connections• Adjust alarm horn volume: rotate horn cover

• Power on

Basic Operating Procedures

• Normal monitoring• Alarms

Normal Monitoring

• Fixed site monitor− Power On when used or 24/7− Check status LEDs and display periodically

• Network monitoring− May be used as additional remote monitor

Respond to Alarms

Type of Alarm• Dose rate alarm

− High: fast beep + High LED− Low: slow beep + Low LED

• Detector Fail alarm− Det Fail LED + steady tone

• Low battery Alarm− Low Bat + Det Fail LEDs

• Overload alarm− Display “OL” + Det Fail LED

Required Actions • Take immediate action to

investigate cause − Reset latched alarm

• Check power supply; return for service

• Check power supply

• Take immediate action to Investigate cause

Equipment Application

• Fixed site monitor− Mount near entry to monitored location− Alerts occupants to source coming in/near door

• Security monitors the remote or PC

Operator Care and Cleaning

• Power Off and unplug before cleaning• Wipe exterior surfaces clean• Do not submerse• Avoid solvents that could damage

polyurethane paint

Area Monitor Summary

• Recognize capabilities, limitations, uses• Recognize components, controls, indicators• Know how to operate

Operator Competency Check

• For each instrument:− Prepare for operation− Check readings− Shut down

• For dosimeters: explain how it is worn and used• For survey meters: explain survey procedures

− People, equipment, vehicles

New Equipment Summary

• Familiarization with the equipment• Basic operating procedures• Basic operator maintenance