Evaluation of Infra-Red Thermometers Global Sensors Evaluation of Infra-Red Thermometers

What is an Infra-Red thermometer? Obtains temperature reading from a distance Held in hand and pointed at a target Often uses a laser beam to guide targeting Digital temperature reading Laser aiming (Optional) Finger pulls trigger to activate reading All are battery powered.

Advantages of Infra-Red Thermometers Quick…gives instantaneous result Proven accurate and useful when used properly Very robust and stable…holds calibration well

Who uses Infra-Red thermometers? Food preparation workers Food safety professionals Catering and food service personnel A Nurses Doctors Health Care workers Screeners for epidemic diseases Wide range of health care personnel B Machine technicians in many industries Air Conditioning diagnosis personnel Electrical technicians C

Types of Infra-Red Thermometers FOOD Optimized for food temperature ranges Often have probe thermometer integrated Effective in presence of vapors from hot food HACCP compliant A HEALTH Do not use laser aiming function Optimized for narrow range of body temperatures Set up for close range use…lighter and smaller B TECHNICAL Wider temperature ranges, less accuracy overall Special functions are industry specific Larger size, generally C

Selecting an Infra-Red Thermometer A Typical distance to target? External Probe? Laser controllable? HACCP functions included? Accuracy? Long Distance Ratio (above 12:1) is impractical for close range monitoring (less than 1 meter) Accuracy of ~1°C is desirable for best decision-making Laser useful in setting up procedures…but Not advisable for use in air travel situation Built-in HACCP functions are good if compliance is required…but not necessary Probe is useful for relating surface temperatures to deeper temperatures Not advisable for use in air travel situation

About Laser Aiming and Ratios Should be inactivated for use in public situations Useful for training or instrument familiarization Ratio low = too close to target – hard to use? Ratio high = too “variable” at close range Typical Ratio Good spot size for close range measurements

Optimum Selections Infra-Red Thermometers A AQA 1721 FI-40L Infrared-LC GSIR-1 Dual Range Pocket IR ThermaTwin™ AQA 1515 DualTemp 2 IR

Types of Infra-Red Thermometers Unit Probe IR Accuracy Ratio Dist/Spot Laser HACCPReady Comment Infrared-LC None >1°C 10:1 Yes No Recommended #2 FI-40L <1°C 12:1 Recommended #1 AQA 1721 Plug-in* 1°C 16:1 Not for close-up GSIR-1 6:1 Hot food ThermaTwin 11:1 Complex functions Pocket IR Built-in 0.6°C 2.5:1 Low ratio AQA 1515 4:1 Sensor on bottom DualTemp 2 3:1 * Requires purchase of separate thermocouple probe

Important Infra-Red Facts: Skin Temperatures Surface Temperature Core Temperature Infra-Red Thermometers measure surface temperature Usually not a lot of difference Use probe to confirm relationship (surface / core) Relationship tends to be quite constant

Important Infra-Red Facts: Surface type Cannot directly measure metal or shiny surfaces Aim at food directly Dull surface packaging OK Water “beads” may be reflective

Important Infra-Red Facts: Features* AVERAGE HIGH / LOW HOLD (also called LOCK) STORE LOW ALARM / HIGH ALARM BACK LIGHT AUTO-OFF * Different products may have one or more of these features. No product has all of these features.

Important Infra-Red Facts: “Emissivity” Infra-Red ideal target is a flat black surface Different reflectivity, color and “depth” change the ..response Some units have adjustment function (Infrared-LC) Not really needed for food Infra-Red thermometers Emissivity for flat black target = 1.0 Food ranges from 0.95 to 0.95 Other surfaces may go as low as 0.8

Important Infra-Red Facts: Laser Function Control Unit with Laser Laser “Switch Off” Laser “Cover” Infrared-LC Has Switch N/A FI-40L No Switch Yes, foil dot AQA 1721 GSIR-1 No cover ThermaTwin

Recommended FI-40L Infrared-LC Very Good Accuracy Excellent Accuracy Laser On-Off Adjustable Emissivity Good Dist/Spot Ratio Backlit 9V battery Excellent Accuracy Laser can be deactivated Emissivity preset to best value (0.97) Good Dist/Spot Ratio Backlit MAX function Battery Indicator 2 AAA batteries