8 replies to this topic

[Bets]

I have a couple of refrigerators that are in employee lounges and we record the time and temperature. How do you guys deal if the temperature exceeds the required tolerance. Often times they are opened quite a bit because its an employee fridge and the temperature will rise out of my spec. But it is not that it is functioning. How would you address this non-conformance.

And would you even consider a non-conformance/out of spec?

[Charles.C]

Dear Bets,

What are the specs / monitoring frequency and what were the size(s) of the non-conformance ?

Rgds / Charles.C

[Soda]

Possibly have a kiy on where you record your temps.
DR = Door open (you might have time allowances to coincide with breaks, where you would expect this to happen.
* = Defrost
c = Cleaning

You could have corrective action as adjust temp settings. Or make allowance in your procedure i.e. if it was out of spec for longer than a certain period of time you would do x.

[Bets]

Dear Bets,

What are the specs / monitoring frequency and what were the size(s) of the non-conformance ?

Rgds / Charles.C

Refrigerator is less than 4C and freezers are less than 0C. Frequency is twice a day once in the morning and once in the afternoon, and the non conformance is plus 5 degrees at max at times. When we go to records the temps they can be at around 8C for refrigerator.

[Charles.C]

Dear Bets,

I hv seen the same problem in cold room monitoring where the fans are temporarily stopped for defrosting. However in this case there is often a continuous monitoring output which clearly shows the pattern / reason for variation and also that the variation is very short so no audit problem.

Basically you are stating that the thermometer is not suitable, ie wrong. Unfortunately yr monitoring is insufficient to prove how much incorrect, ie you need to inc. the frequency to prove yr point. Maybe the temperature is genuinely not under good control ?. So maybe you should change yr procedure, eg monitor +0degC levels using a beaker of water with a thermocouple in it. This effectively buffers short temperature variations IMEX. Or change the frequency so that you can validate something like previous post.

I presume yr query only relates to the >0degC section ?

Rgds / Charles.C

[Bets]

Very nice charles great idea on using a beaker of water with a thermocouple in it. So I did a little researching and found some thermometers that are perfect and actually made for this type of variation. I will try them out, and thanks for relieving that little big headache.

Edited by Bets, 17 October 2008 - 04:26 PM.

[GMO]

I also think 4 degrees for a staff fridge is unreasonable. The legal limit in the UK is 8 degrees and in a staff fridge the food is likely to be stored there for less than 8 hours.

I suggest having a target of 5 degrees and a limit of 8 but I also agree with the advice above, if the door has been open for a long time, the air go out of spec even if the food in there is still cold. When measuring a fridge temperature as well if you don't use the water system, it's best to leave the thermometer in there for a long time (go off for 15 mins and get a cup of tea!)

That all said, don't ignore it if after doing all that you get something like 10 degrees! I once had a canteen who had recorded out of spec temperatures themselves for a month! This canteen was in a food factory and the workers were buying the sandwiches from this fridge. The response was "I've reported it to the engineers". I measured the temperatures and found only the well was ever cold enough, not the display shelves. After weeks of telling them not to use the shelves and then finding they were as soon as my back was turned, then me throwing away the stock, eventually an ex EHO visited and explained to me that only the well should be used as the shelves were not refridgerated in that design which was good because we then knew why and could enforce not using the shelves. The funny bit was that the person who told me this had written the HACCP study for the canteen and not raised this!!!!!!!!!!!

[Simon]

Similar to you GMO we purchased a normal home type fridge for employees to store their sandwiches and cold drinks. We had a thermometer in situ and it never went much below 10C even on the coldest setting. I think maybe this was because there was so much stuff in there and most of it was stored in plastic bags like you get from the supermarket and also because the door was opened many times. It just wouldn’t go any colder, so we accepted that about 8C give or take a couple of degrees was ok. We did however have a very strict emptying and cleaning procedure. Every Saturday anything left in the fridge was dumped and it was cleaned and sanitised top to bottom.

[Charles.C]

Dear All,

The subject of appropriate refrigerator temperature seems to be yet another of these simple questions which actually have very diverse answers. Interested to know GMO’s source of 8degC ?

I compiled below some supposedly official UK (first) / US links though the UK links were elusive as to their source. The latter may be as given in this detailed survey / publication which has refs thru 2005.

The temperature at which a refrigerator operates is critical for the safe storage of chilled food. Recommendations in the UK concerning the microbiological safety of foods advise that maximum temperatures in domestic refrigerators should not exceed 5°C (Richmond, 1991).

http://www.frperc.br...ems/item0002.ht
and -

Check the refrigerator temperature at least every day, the refrigerator operating
temperature should be between O°C and 8°C. Keep a written record of temperature checks.

http://www.eastridin...s_advice_04.pdf
and -

Check the refrigerator temperature at least every day, the refrigerator operating temperature must be at or below 8°C (Ideally 0-5ºC). Keep a written record of temperature checks.

http://www.harlow.go...frigerators.doc.
and lastly for UK -

The normal recommended refrigerator temperature is between 1-4 degrees C for high risk foods. Refrigeration is a form of delaying and not preventing food spoilage.

http://www.rushcliff...oc.asp?cat=8459
(rather nicely presented article IMO)

Some selective extracting from a main ref. is possibly occurring ?

In contrast US refs seem more rigid to pathogenic control logic, eg –

For safety, it is important to verify the temperature of the refrigerator. Refrigerators should be set to maintain a temperature of 40 °F or below. An appliance thermometer can be kept in the refrigerator to monitor the temperature. This can be critical in the event of a power outage. When the power goes back on, if the refrigerator is still 40 °F, the food is safe. Foods held at temperatures above 40 °F for more than 2 hours should not be consumed.

http://www.fsis.usda...afety/index.asp
(40degF is about 4.4degC. The last sentence above seems intuitively very protectionist [especially when compared to the UK links] but I suppose someone has done some maths ?)
and -

Freezers should be kept at 0F (minus 18C) or lower and refrigerators should be at 40F (5C) or lower, but not so cold as to freeze.

http://www.essortmen...ageref_sapw.htm

In addition to the numerical links above, I noticed some other related issues –

Both “relaxed” temp. viewpoints and strictly pathogenic control logics have implications, and occasionally conflicts, within the big macro-bacterial picture, eg this extract –

 bacteria__temp._aspects.jpg   118.42KB   61 downloads

Also there is the question of expiry dates –

Refrigerator temperature is just as important as freezer temperature. Expiration dates on refrigerated foods such as milk are based on the supposition that the food is kept at the proper temperature. Produce is immediately affected by too cold or too warm temperatures. Lettuce gets moldy. Strawberries turn to slime. Sometimes produce freezes ruining the product.

http://www.essortmen...ageref_sapw.htm

The above link also has another option for checking product temperature –

Place the freezer thermometer between two frozen objects such as two packages of vegetables and leave it for at least 24 hours before checking. Place the refrigerator thermometer between objects too, such as between two cartons of milk. This is so that the thermometer gives you a better picture of the consistent temperature rather than quick fluctuations as when the door is opened.

I hv used the freezer variation in cold rooms and refrigerated containers. It works much faster than 24hrs IMEX.

Another of the links also suggested an infra-red gun. Looks very convenient but probably not cheap.

Rgds / Charles.C