Ultra low freezer thermometers, best practices?

duff999

Quite Involved in Discussions
#1
Hi All

We recently had a supplier audit and we were challenged on our freezer temperature monitoring. Currently we have several negative 80 freezers, and we do spot temperature checks twice a day. Does any one have any best practice suggestions on how others are monitoring their freezers, using calibrated thermometers in several different locations inside the freezer.

We do plan on installing a temperature monitoring systems, but currently it is not active.

Do we have any recommendations on what type of traceable thermometers I should be using.

Any help is greatly appreciated.
 
Elsmar Forum Sponsor

Tidge

Trusted Information Resource
#2
I have only limited experience with freezers, but if you are concerned with temperature excursions I can describe what did a million years ago when I was worried about something getting "too warm". "Too cold" was not a concern in my application.

I used an OMRON brand temperature controller that allowed me to set two different alarm conditions (monitoring a type K thermocouple). The lower alarm condition would trigger the cooling system, my intention was to keep the area below a certain temperature and I had studies that allowed me to set this alarm limit. The second alarm condition was set at my excursion point and I wired in a relay that would energize and lock an indicator lamp ON... there was a push button that could be used to de-energize the relay. This setup let me know at a glance if there had been a temperature excursion without having to go back and scrub the logged data. The same principle can be applied if you want to set up an indicator for excursions at the other end of the temperature scale.
 

Zero_yield

"You can observe a lot by just watching."
#3
For our freezers (and ovens and refrigerators), we do charts (physical or electronic) that can be reviewed to confirm the equipment stayed at the proper temperature for the documented time. We also do audible alarms for if the temperature falls out of spec.
 

BradM

Leader
Admin
#4
Hello there!

So first, a little more about what you currently have. You have freezers, and in each of them there are thermometers located throughout. Were the locations part of a mapping study (min/max/ average)? How did you determine how many went in the freezer?

You say you perform spot temperature checks twice a day. Does that involve opening the freezers, observing the thermometers, and writing those values down somewhere?
 

duff999

Quite Involved in Discussions
#5
Hello there!

So first, a little more about what you currently have. You have freezers, and in each of them there are thermometers located throughout. Were the locations part of a mapping study (min/max/ average)? How did you determine how many went in the freezer?

You say you perform spot temperature checks twice a day. Does that involve opening the freezers, observing the thermometers, and writing those values down somewhere?
Thanks for the reply Brad.

We have not done an official mapping study, however this was brought up during the audit, and there concern were "hot spots".

For the spot check, we do have thermometers in the freezers that are read by the lab personal during their morning and evening walk throughs. My thought was to purchase additional traceable thermometers that can handle the negative 80 spec's. For the mapping, I will have to do additional research as to where the optimal placement would be for these.
 

Tidge

Trusted Information Resource
#6
For our freezers (and ovens and refrigerators), we do charts (physical or electronic) that can be reviewed to confirm the equipment stayed at the proper temperature for the documented time. We also do audible alarms for if the temperature falls out of spec.
For the past case I described, I was concerned that there might be an excursion when no one was around to witness the alarm, and I didn't want to have to wait for people to review charts to know if there had been an excursion. I suppose if the alarm indicator doesn't deactivate if the excursion goes away, this is less of a concern.
 

dwperron

Trusted Information Resource
#7
These days with the availability of inexpensive digital thermometer / dataloggers out there I cannot understand why they are not being used on every temperature chamber that needs "calibration". A constant log of chamber temperatures, the ability to set alarms, placement of probe(s) in critical areas, all justify the relatively small expense involved.
I have never understood the idea of taking a snapshot of the temperature twice a day as being adequate to demonstrate that the chamber maintained temperature for a product or process, never mind those places that expect an annual calibration to be adequate for that job!
 

BradM

Leader
Admin
#8
These days with the availability of inexpensive digital thermometer / dataloggers out there I cannot understand why they are not being used on every temperature chamber that needs "calibration". A constant log of chamber temperatures, the ability to set alarms, placement of probe(s) in critical areas, all justify the relatively small expense involved.
I have never understood the idea of taking a snapshot of the temperature twice a day as being adequate to demonstrate that the chamber maintained temperature for a product or process, never mind those places that expect an annual calibration to be adequate for that job!
Good points.

Minimally, you can put some thermometers in there, run the wire out the door and connect to something. That way the door doesn't need to be opened to take readings.
 

BradM

Leader
Admin
#9
Thanks for the reply Brad.

We have not done an official mapping study, however this was brought up during the audit, and there concern were "hot spots".

For the spot check, we do have thermometers in the freezers that are read by the lab personal during their morning and evening walk throughs. My thought was to purchase additional traceable thermometers that can handle the negative 80 spec's. For the mapping, I will have to do additional research as to where the optimal placement would be for these.
Yes!! I would be concerned with the lack of mapping of the chambers. Are you sure it wasn't done during the initial commission of the chambers?

I would have them mapped. Once they are mapped, I would consider placing a probe in the min/ max/ and average location for temperature mapping.
 
Thread starter Similar threads Forum Replies Date
K Sr Process Engineer (Hillsboro, OR) - SPC Program Focused - Ultra Clean Technology Job Openings, Consulting and Employment Opportunities 0
A Low RH Effect on Elastomeric + Polyester General Measurement Device and Calibration Topics 3
R MSA on set of parts with low variation Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 20
Z REACH compliance for low volume product REACH and RoHS Conversations 1
B Combat Low Part to Part Variation in GRR Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 8
L Requirements for Cables used for Low-Voltage DC Mains (12-36VDC) IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
D Low risk IVD study in the UK, do I need MHRA approval? UK Medical Device Regulations 1
D Deciding whether or not pre-market clinical investigation is required for low risk device EU Medical Device Regulations 5
R DFMEA/PFMEA mitigation of high severity (9-10) in low volume products IATF 16949 - Automotive Quality Systems Standard 1
Proud Liberal Improving low p-value Statistical Analysis Tools, Techniques and SPC 13
D Importing a general wellness low risk product Other US Medical Device Regulations 3
CPhelan Best metrics for monitoring low volume (<1000) parts per vendors Supply Chain Security Management Systems 1
J ISO 14971 applied to ISO 13485? Low risk class 1 devices ISO 13485:2016 - Medical Device Quality Management Systems 5
Q % Study variation low, % tolerance high - GR&R Interpretation help Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
N Use part of high risk device for establishing low risk device EU Medical Device Regulations 0
R Laminate ESD Mats - Low resistance (RTT) readings Manufacturing and Related Processes 6
J Question on very low NDC number with tolerable GRR ratio's Capability, Accuracy and Stability - Processes, Machines, etc. 7
A MDSAP benefit for manufacturer of low-risk devices Canada Medical Device Regulations 3
Rincewind Clinical Evaluation of very low risk medical devices EU Medical Device Regulations 3
L Nonconformity's risk is too low, so don't report it? General Auditing Discussions 25
E Applicability of Low Voltage Directive (LVD) for 12V equipment CE Marking (Conformité Européene) / CB Scheme 4
M Testing a Low Current (Battery) DC Medical Device Other Medical Device Related Standards 4
M Battery Powered Measurement Equipment and Low Voltage Directive CE Marking (Conformité Européene) / CB Scheme 1
G CE Marking - Low Voltage Directive and EMC Directive CE Marking (Conformité Européene) / CB Scheme 4
Marc New FDA guidance on low-risk wellness devices US Food and Drug Administration (FDA) 1
J If/how to apply LVD (Low Voltage Directive) in this case CE Marking (Conformité Européene) / CB Scheme 6
R Looking for good, low cost APQP Software recommendations APQP and PPAP 2
V For screening a design, can we live with the low/poor predicted R-Sq.? Statistical Analysis Tools, Techniques and SPC 3
M Chrysler PSW Sign Off when your product is rated low risk in CQMS IATF 16949 - Automotive Quality Systems Standard 5
S Low Sample Size for Gage R&R Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
M David vs Goliath (Large Suppliers vs Low Volume Purchasers) Supplier Quality Assurance and other Supplier Issues 11
C Hardness Testing - Low Cpk's using Minitab Misc. Quality Assurance and Business Systems Related Topics 10
Wes Bucey A "Feel Good" story - 3D Printing Creates Low-Cost Prosthetic Fingers Coffee Break and Water Cooler Discussions 0
B Determing Machine Capability in a High Mix, Low Volume Sheet Metal Shop Manufacturing and Related Processes 4
Y How to cut off Extremely High and Low Data Statistical Analysis Tools, Techniques and SPC 2
S How to Capture Low Volume Process Info? Lean in Manufacturing and Service Industries 3
M Control Measures for Hazards already deemed Low Risk ISO 14971 - Medical Device Risk Management 6
M Need Machining Low Volume Family Control Plan and PFMEA APQP and PPAP 1
C CE Marking for LVD (Low Voltage Directive) Health and Beauty Products CE Marking (Conformité Européene) / CB Scheme 5
C Suggestions on Sample Plans for High Volume/Low Cost/Low Risk Components Inspection, Prints (Drawings), Testing, Sampling and Related Topics 2
F CE Marked Motors - BS-EN61010 for the Low Voltage Directive CE Marking (Conformité Européene) / CB Scheme 1
S FMEA Manual aimed at Low Volume Fabrication Industry FMEA and Control Plans 1
B Understanding why my CpK and PpK are low, and LCL Statistical Analysis Tools, Techniques and SPC 20
N Extent of Product Traceability Required by ISO 13485 (Low Level Class I Devices) ISO 13485:2016 - Medical Device Quality Management Systems 3
J CAPA Effectiveness Checks on Low/No Volume Processes Nonconformance and Corrective Action 7
J How to determine a Capability Study for Low-Volume Suppliers Capability, Accuracy and Stability - Processes, Machines, etc. 3
J Use of PPMs in Low Volume Machine Shop AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 5
G ISO 17664 Reusable Low Risk Medical Device Cleaning Other Medical Device Related Standards 2
M Differences between High, Medium, Low Risk Suppliers Supplier Quality Assurance and other Supplier Issues 5
K Probability of Occurrence Ranking for Low Volume Manufacturing vs High Volume FMEA and Control Plans 11

Similar threads

Top Bottom