1. Top 5 Food Safety Thermometer
Mistakes and How to Avoid
Them, Part 2
ThermoWorks “Winning at Food Safety” Webinar Series
Special Guest Martin Earl, Culinary Editor
Oct 21, 2021

2. Top 5 Food Safety Mistakes – Part 2
1. Failing to stir liquids and semi-liquids before measuring
2. Failing to measure the thermal center of foods to find the lowest
food-safe temperature
3. Using an infrared thermometer to test internal food temperatures
4. Using an inaccurate thermometer for critical food safety
measurements and not properly testing its accuracy before use
5. Using paper logs that lead to erroneous data when digital
solutions are readily available
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3. Tom Wiandt
• graduated 1982 from US Air Force Precision Measurement
Equipment Lab
• has worked in DoD, nuclear power, instrument manufacturing,
laboratory accreditation, and independent consulting
• positions at Fluke, Hart Scientific, Southern California Edison,
Northrop, USAF before joining ThermoWorks
• trainer, consultant, and laboratory assessor for NVLAP, A2LA, and LAB
• member of ASTM since 1995—Chairman of ASTM E20 on
Temperature Measurement from 2012 to 2017
• awarded the Award of Merit and granted the title of ASTM Fellow in
2011, the highest award presented by ASTM
• Chief Metrologist at ThermoWorks since 2018
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4. Mistake #4 - How Accurate Should a
Food Thermometer Be?
4-203.11 Temperature Measuring Devices, Food.
(A) FOOD TEMPERATURE MEASURING DEVICES that are scaled only in
Celsius or dually scaled in Celsius and Fahrenheit shall be accurate to
±1°C in the intended range of use.
(B) FOOD TEMPERATURE MEASURING DEVICES that are scaled only in
Fahrenheit shall be accurate to ±2°F in the intended range of use.
(FDA Food Code 2017)
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5. Components of Accuracy,
“System Accuracy”
• Find the accuracies listed by the
manufacturer
• Add up all accuracy
specifications of meter + probe
• Consider any accuracy
restrictions by the manufacturer
• Ambient conditions
• Interchangeability of probes
Meter and probe uncertainty must
be combined to arrive at system
accuracy.
(±0.7°F + ±0.5°F = ±1.2°F combined)
Meter and probe combined in
manufacture, calibrated as a system
for higher accuracy.
(±0.5°F combined)
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6. Competitor Accuracy Calculation
• Meter: ±0.5°F* in ambient from 68-86°F,
0.1°F per degree outside range
• Probe: ±1.0°F*
In Room Temp (75°F): ±1.5°F system accuracy
In Walk-in (38°F): ±4.0°F system accuracy
(DOES NOT MEET FOOD CODE – DO NOT USE!)
*manufacturer’s published specification
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7. How Do You Know Its Accurate and
Meets Food Code Requirements?
• Check the manufacturer’s specifications carefully
• Make sure you include all the components (accuracy
specifications of meter and probe and within normal
operating range)
• Always insist on getting a calibration certificate from the
manufacturer so you know they individually calibrated the
thermometer
• Check it in a properly made ice bath or against a reference
standard regularly to verify its accuracy
• Periodically send the thermometer in to a calibration lab for
a regularly scheduled calibration (i.e. annually)
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8. Ice Bath Calibration Do’s and Don’ts
• Do use small cubes/crushed
ice
• Do fill container full of ice, and
water ½ inch below ice level
(No ice should be floating off
the bottom)
• Do plunge tip into slurry, and
stir while testing
• 32°F ±0.05°F is achievable!
• Don’t use large cubes – will
cause pockets/gradients
• Don’t allow ice to float off
bottom – could be up to 10°F
off
• Don’t insert probe tip less
than 2-inches into slurry
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9. Improper Ice Bath Video
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10. Proper Ice Bath Video
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11. Correctly Made Ice Bath
Correct Incorrect
Water temp under
ice slurry will be
warmer than 32°F
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12. Downloadable Ice Bath Poster
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13. Mistake #5 – Erroneous Paper Logs –
What Can Go Wrong?
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14. Martin Earl, Culinary Editor
• graduated 2007 from University of Utah with a BS in physics
• MA in History and Philosophy of Science from Indiana University
Bloomington
• Associate’s Degree in Culinary Arts/Chef Training from Ivy Tech,
Bloomington
• executive chef at C3 in Bloomington
• has worked as a copy editor, cheese monger, culinary sales specialist,
dining hall manager, sous chef, and executive chef
• certified food handler, ServeSafe, trainer in food safety
• Culinary Editor at ThermoWorks since 2017 where he oversees both the
culinary operations in our demo kitchen/BBQ patio and the writing and
customer engagement on the ThermoBlog (blog.thermoworks.com)
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15. Mistake #5 – Erroneous Paper Logs –
What Can Go Wrong?
• Temperature reading doesn’t ‘lock in’, user
has to decide what number to use
• Changing the display units to Celsius and
recording the reading in the wrong scale
• Writing down the wrong number on paper
log
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16. Pencil Whip Video
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17. Mistake #5 – Erroneous Paper Logs –
What Can Go Wrong? (cont.)
• Pencil whipping the day before the health
inspector comes, not actually doing it
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18. Mistake #5 – Erroneous Paper Logs –
What Can Go Wrong? (cont.)
• Logbook gets lost, wet, or filed erroneously
• User doesn’t actually correct the food safety
breach—nothing indicates a problem to them
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19. Go Paperless – More Accurate
Line Checks
• Readings recorded electronically – no user
reading or recording errors
• User prompted to correct food safety
problem immediately with corrective action
suggestions, protects brand
• Historical data filed and archived
electronically
• Visibility to all stakeholders that check was
completed, done on time, and with no issues
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20. Go Paperless – More Accurate
Line Checks (cont.)
• Health Department confidence in
readings
• Cost savings gained – less time
• Users report more ‘fun’ with
mobile app and more familiar
with technology and pencils
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21. Bluetooth Demo Video
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22. Why a National Donut Chain
Went Paperless
“It is the future; we have embraced technology and have
gone to an electronic line check using a Bluetooth
connected thermometer because:
1. “Ease of use. It is easy to do the line check with the
tablet in one hand the thermometer in the other.
2. “Speed, it is much faster to complete the check using
an electronic system with a connected thermometer.
3. “Accuracy, it is a more accurate way to
document your temperatures; all the dates, times,
and temperatures are captured simultaneously.
4. “Better traceability and oversight; we can see who
and when the line check was taken.”
—Senior Food Safety Manager for a National Donut Chain
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23. Downloadable Bluetooth Thermometer
Guide
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24. Helpful products
FREE Ice Bath Mug with
Any Purchase
Thermapen ONE
Accurate to ±0.5°F with full
readings in 1 second or less
5-year warranty
With printed instructions
for proper ice bath
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25. Bluetooth products
20% Off TempTest 2 Blue
20% Off Thermapen Blue
Interchangeable probe
design for versatility, with
auto-rotating LCD display
All the speed, accuracy, and
convenience of Thermapen
Mk4 with Bluetooth
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26. Next Session:
Thursday, December 2nd, 10:00-10:30am MDT
• The HACCP Show: What It Is and How It Can Power-up Your Kitchen Ops
• How small operations can do what the big guys do to dramatically increase efficiency…
This Session:
• Replay of this session going out by email
• Go to www.thermoworks.com/webinar-series
• Share with colleagues and friends
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