
CALIBRATION
✓ SAFETY METRICS
✓ TRAINING
✓ TRACKING
BEFORE CONDUCTING CALIBRATION,
ARE YOU TRAINED?
IF NOT, READ BELOW AND TAKE THE TEST
Calibration (SQF CLAUSE 12.2.3)
Methods and Responsibilities for Calibration of Equipment
(Background Scope: Element 12.2.3.1)
The methods and responsibility for calibration and re-calibration of measuring, testing, and inspection equipment used for monitoring activities outlined in pre-requisite programs, food safety plans, and other process controls, or to demonstrate compliance with customer specifications, shall be documented and implemented. Software used for such activities shall be validated and secured as appropriate.
Equipment Calibration Standards
(Background Scope: Element 12.2.3.2)
Equipment shall be calibrated against national or international reference standards and methods or to an accuracy appropriate to its use. In cases where standards are not available, the site shall provide evidence to support the calibration reference method applied. A list of measuring, testing, and/or inspection equipment requiring calibration shall be maintained.
Instructions:
Twin City Produce, Springdale is a Produce and Food product Storage and Distribution Company.
While we do not manufacturer, we do ensure the safety of food by monitoring temperature. We monitor temperature during storage and delivery.
This procedure ensures that all measuring devices used in production of product or those used to monitor measurements are properly calibrated.
We use scales for our EA/LB, Refrigerated Trailers and Coolers.
All require calibration. Calibration records and logs are digital and stored on the Company Intranet. Per the calibration program requirements, the Safety Team member performs the following procedure:
Instructions:
- At each internal audit, the auditor signature/initial, verifies there were no NCR’s issued against the Warehouse, as evidence the procedure was satisfactorily followed, and each piece of equipment’s calibration is verified.
- Warehouse personnel are responsible for recording each measuring equipment on the master log, indicating the equipment by name, serial or unique identifying number, its location in the site during use and/or storage.
- The frequency of calibration for each measuring device will be found on the master log. The frequency of calibration shall be in accordance with manufacturers suggested time frames but no less than once every three months. Warehouse personnel complete the calibration record for each logged piece of equipment, including the
- Date calibrated
- Results, and
- Date for the next calibration test
- The calibration procedure is in accordance with manufacturers’ suggested methods.
- In the absence of such instructions the calibration of measuring devices is made against the master certified device.
- Take a temperature or measurement with the master
- Repeat the temperature or measurement with the device to be calibrated.
- Record the results of both in the Calibration Log
- Return all equipment within tolerance suggested by the manufacturer to service.
- Remove any equipment outside of tolerance from service, replace with calibrated equipment, and immediately notify the Warehouse Manager.
- The Warehouse Manager will determine whether to repair or dispose and replace the non-compliant equipment. Any repair is completed by a qualified subcontractor.
Measuring Tools:
The thermometers are calibrated against the Warehouse’s traceable thermometer which has been certified by the National Institute of Standards and Technology (NIST).
The calibration test is the responsibility of the Warehouse Manager or designated employee.
The test is performed by measuring the same medium with the test thermometer and traceable thermometer and comparing the measurement.
The reading of the test thermometer must be within +/- 2 deg. (F) of the traceable thermometer.
Tool:
Twin City Produce uses the Digi-Sense Traceable T-Bar Waterproof Food Thermometer Ultra with Calibration; +/- 0.4ₒC accuracy at tested points (UX-98767-39)
Regulatory Requirements and Schedule
(Element 12.2.3.3)
Calibration shall be performed according to regulatory requirements and/or to the equipment manufacturers’ recommended schedule.
- Schedule:
- Calibration of thermometers in coolers is done quarterly, by putting thermometer in ice water and verified against NIST thermometer.
- Scales are tested and calibrated annually by a 3rd-party vendor, GT Mitchell Co., Inc, Springdale, AR 888-345-9731, affixing a tag with date of calibration on scales.
- Compliance:
- Thermometers not within the specified range are removed from service and replaced with a calibrated thermometer.
Procedures for Disposition
Procedures shall be documented and implemented to address the disposition of potentially affected products should measuring, testing, and inspection equipment be found to be out of calibration state.
Instructions:
- Any product that may be affected by thermometer would be a quality issue not a biological issue if they fail to pass calibration. There will be a visual inspection on all affected product, and if determined to be bad, product would be disposed of, as determined by the Warehouse Manager or SSM.
Directory of Equipment Requiring Calibration:
Background Scope Element 12.2.3.5
A directory of measuring, testing, and inspection equipment requiring calibration and records of calibration tests shall be maintained.
History of Calibration
Organic Calibration
Some measurements can be taken with the tool, but what it the temperature monitoring is inside a tube?

Nickel on a Scale
Believe it or not, this is still an acceptable measurement for food scales. And since a nickel still weighs 5 grams, place one on a clean scale set to grams. If your read out is 5g, we are good to go!
Paper Recordkeeping
Before transitioning to digital, calibration was completed on paper. Any equipment change required updates in a dozen of places. However during that time we learned some really important tips that can help you with calibration.

Calibration Log
The original calibration logs are extremely valuable tools. Not only do they show the process behind the determinations, they serve as a contingency should we need to conduct a calibration audit and the internet goes down.
We maintained a separate log for each type of equipment requiring calibration.
- Refrigerated Trailers
- Coolers
- Scales
Take a moment and review each page.
How to determine if equipment is calibrated?
For example, Trailers require three readings:
- The cab read out
- The trailer read out
- The tool’s read out.
What is the nominal reading? That is the reading from the equipment.
What is measured? That is the reading from the calibrating tool.
What is corrected? If the equipment is out of calibration, you do not correct it. This is updated once the Contractor returns to repair the equipment.
What are limits? The minimum and maximum temperature.
