19 replies to this topic

[cazyncymru]

I'm currently writing a validation report for our Biotrace swabbing. We use the limit that a pass is <100rlu's. (Historic figure from my predecessor). I've looked on the 3M website and downloaded the CARA whitepapers etc but there's nothing on the website to tell me how to set my limits.

 

Anybody have any ideas on how i justify setting my limits?

 

Caz x

[Oldairyman]

Sorry that is why ATP is so "hoaky" . But you can test retest , test and retest against your oun accutual micro testing aerobic counts or standard plate counts . Find liturature to see if your application works with ATP. For example high fat environments ,... not so good. If you swab after some sanitizers ,.. not so accurate. Protien , blood residuals, sugars , calcified bio films works great. 

Personally dont use them , they are a waste of time , money, not accurate. A good salesman will tell you different because it's about the money.

[S Claw]

I agree. We attempted to do something similar. What I found is that any literature supporting the efficacy of ATP sampling is usually produced/published by an ATP reader-swab producer company.

 

ATP has many limitations and the variance between vendors is startling. 

[Charles.C]

Based on numerous previous threads, it seems clear that there are both (user) positive and negative validations of the usefulness of atp instruments.

Like so many things in life.

 

@Caz, it's a fact/criticism, as you  are probably aware, that every (well, many) atp units tend to have their own RLU guidelines due the specific instrumentation. I haven't checked for Biotrace but i'm surprised if they offer no advice for precisely this reason.

 

Some suppliers of atp units do include generic methods to set up limits ( in anticipation of the provided manual's guidelines  being possibly ineffective). I enclose one sample extract from a supplier (maybe Hygiena ), can probably dig out the original source if you wish. You may not agree with the logic employed   . Other techniques also exist.

 

 RLU guideline settings.xls   126.5KB   381 downloads

 

Rgds / Charles

[HARPC]

Based on numerous previous threads, it seems clear that there are both (user) positive and negative validations of the usefulness of atp instruments.

Like so many things in life.

 

@Caz, it's a fact/criticism, as you  are probably aware, that every (well, many) atp units tend to have their own RLU guidelines due the specific instrumentation. I haven't checked for Biotrace but i'm surprised if they offer no advice for precisely this reason.

 

Some suppliers of atp units do include generic methods to set up limits ( in anticipation of the provided manual's guidelines  being possibly ineffective). I enclose one sample extract from a supplier (maybe Hygiena ), can probably dig out the original source if you wish. You may not agree with the logic employed   . Other techniques also exist.

 

RLU guideline settings.xls

 

Rgds / Charles

 

This RLU guideline settings is also what Ecolab and Charm Sciences recommend.

 

Regards,

Bill

[Charles.C]

This RLU guideline settings is also what Ecolab and Charm Sciences recommend.

 

Regards,

Bill

 

Dear sci,

 

Thks for input.

 

After a bit of archive digging i think the extract was probably from here -

 

http://www.hygiena.net/faq-09.html

 

But you may well be correct as well (never used  atp myself).

 

It's sort of interesting that Ecolab are not enthusiastic regarding atp usage in health care environment

 

http://www.issa.com/...=1&category=117

 

Rgds / Charles.C

[HARPC]

Charles,

   great read on the ATP usage in health care environment.

 

Sincerely,

Bill

[cazyncymru]

Based on numerous previous threads, it seems clear that there are both (user) positive and negative validations of the usefulness of atp instruments.

Like so many things in life.

 

@Caz, it's a fact/criticism, as you  are probably aware, that every (well, many) atp units tend to have their own RLU guidelines due the specific instrumentation. I haven't checked for Biotrace but i'm surprised if they offer no advice for precisely this reason.

 

Some suppliers of atp units do include generic methods to set up limits ( in anticipation of the provided manual's guidelines  being possibly ineffective). I enclose one sample extract from a supplier (maybe Hygiena ), can probably dig out the original source if you wish. You may not agree with the logic employed   . Other techniques also exist.

 

RLU guideline settings.xls

 

Rgds / Charles

Hi Charles

 

i used this, though i cheated slightly, and took the last 50 results from the area swabbed, worked out the mean and then the standard deviation, and my fail limit was 18!!

 

Mind if this was for hygiena, then theoretically i could multiply by 10 (as hygiena reads lower than biotrace) ; though i'd have to check the correlation factor

 

Caz x

[Charles.C]

I'm currently writing a validation report for our Biotrace swabbing. We use the limit that a pass is <100rlu's. (Historic figure from my predecessor). I've looked on the 3M website and downloaded the CARA whitepapers etc but there's nothing on the website to tell me how to set my limits.

 

Anybody have any ideas on how i justify setting my limits?

 

Caz x

Dear Caz,

 

Not sure if the attached helps or not. Support yes, Validation Hmmm.

I suspect no help but never mind. At least it looks more user-friendly than 100.

 

I am guessing most people use manuf. limits if they give usable results for 90% (?) cases as per users opinion on cleanliness. if otherwise the hunt begins.

 

 3m-clean-trace pass-fail limits.pdf   378.79KB   405 downloads

[JMiller]

Our rep set our program up and their starting guideline is 150 is pass and 300 is fail.  They told me to use this as a guide to start and as I collect more data, I develop my own verification as to whether these standards are acceptable for our own facility.  They said as we go on, we will likely make our pass/ fails closer to 75/150

[Charles.C]

Our rep set our program up and their starting guideline is 150 is pass and 300 is fail.  They told me to use this as a guide to start and as I collect more data, I develop my own verification as to whether these standards are acceptable for our own facility.  They said as we go on, we will likely make our pass/ fails closer to 75/150

Dear jaimemillertime,

 

You might consider asking yr rep as to his validatory data. It's probably a piece of paper from Head Office.

 

Rgds / Charles.C

[fgjuadi]

We use ATP to validate sanitation and it's cheap, quick, and easy.  Also way better than nothing/visual inspection, which is what we were using before.  The other day, I was talking to a batch maker about using sanitizer, and he said "I use it now, cuz if I don't, it won't pass the clean test"  and instead of them coming to ask me if I think it's clean, I can show them NUMBERS, like, RIGHT NOW numbers.  They trust numbers.  AND it's all electronic, so, I have a nice and easy to trend record of the fail tests & recleans with time, so I can look at runs that fail sensory (theoretically, I've never had to investigate .a sensory fail yet becuase we're still training sensory panels)

 

We have a Hygenia kit (it was laying there unused for two years! Pobrecito!), and we use the limits they recommend - under 30 is clean. We're collecting a good amount of data, so I will average and adjust as needed.

[Charles.C]

We use ATP to validate sanitation and it's cheap, quick, and easy.  Also way better than nothing/visual inspection, which is what we were using before.  The other day, I was talking to a batch maker about using sanitizer, and he said "I use it now, cuz if I don't, it won't pass the clean test"  and instead of them coming to ask me if I think it's clean, I can show them NUMBERS, like, RIGHT NOW numbers.  They trust numbers.  AND it's all electronic, so, I have a nice and easy to trend record of the fail tests & recleans with time, so I can look at runs that fail sensory (theoretically, I've never had to investigate .a sensory fail yet becuase we're still training sensory panels)

 

We have a Hygenia kit (it was laying there unused for two years! Pobrecito!), and we use the limits they recommend - under 30 is clean. We're collecting a good amount of data, so I will average and adjust as needed.

Dear m_m,

 

With all due respect yr post is a trifle scary.

 

Validation requires Verification, as implicitly emphasised by the NACMCF HACCP

 

Rgds / Charles.C

[cazyncymru]

I think there's confusion here over validation and verification!

 

I use my ATP swabs, after each clean to VERIFY that the plant is clean (or not)

 

The question that I was asking is how would I VALIDATE the limits that are set for Pass / Fail

 

Caz x

[fgjuadi]

Dear m_m,

 

With all due respect yr post is a trifle scary.

 

Validation requires Verification, as implicitly emphasised by the NACMCF HACCP

 

Rgds / Charles.C

 

Crap, it seemed so much better than the nothing we were doing before and it's way easier to give critical feedback when a machine is doing it

 

I probably meant verify cleaning with ATP and validate with the Hygenia white papers.
(Ha, Caz posted the same thing.  This is the confusion)

 

  But now I'm a little scared - what's the gap there?  Needing a validation study cuz the manufacturer white papers aren't sound?

Edited by magenta_majors, 20 March 2014 - 09:37 AM.

[cazyncymru]

M_M

 

As part of your validation program , you can reference the white papers, they are scientific studies carried out by the manufacturer, and as such have some credibility. But they cannot format the entirety of your validation. they are support documents.

 

Be aware, sometimes you can get false results if there are residues of sanitizer left on the plant. You should swab before sanitizing.

 

Caz x

[fgjuadi]

M_M

 

As part of your validation program , you can reference the white papers, they are scientific studies carried out by the manufacturer, and as such have some credibility. But they cannot format the entirety of your validation. they are support documents.

 

Be aware, sometimes you can get false results if there are residues of sanitizer left on the plant. You should swab before sanitizing.

 

Caz x

Damn!  I mean thanks, but also, damn, now I have to do a validation study for ATP when I thought their bullshit brochure was good enough xD   I have an allergen clean out validation study for each allergen, but I've never done one for just clean.  Here we are, in the same boat.  That one janky form Charles posted for all!

 

I've used quat strips to test for sanitizer residue in the past for organic and in wet clean / CIP systems, here we are dry cleaning and using no-rinse food contact ppm levels.  I might be missing something here - If it's clean before the sanitizer, why would I use sanitizer? Or, if it's not clean, why would I be swabbing for cleanliness? 

[Charles.C]

Dear m_m,

 

(apologies to Caz, getting a bit OT)

 

Va/Ve terminologies are definitely the 1^st thing to sort out. But maybe not the last.

 

There are also various operational terminologies involved with achieving satisfactory food contact surfaces. To name but a few –

I use cleaning / sanitizing (ie 2 different treatments, detergent then sanitizer, C/S) but other terminologies/some chemicals include S  within the C. Sometimes “cleaning” = C only, sometimes “cleaning” = S only. And sometimes “sanitizing” = C only or C/S. In yr case, no idea.

 

IMO a meaningful assessment of the effectiveness of  C, S, C/S   can (should?) involve at least 2 aspects – ATP characteristics / microbiological characteristics. Both should be within certain “limits”. Some people will opine that using the second cancels any necessity for the first but the reverse is certainly not true IMO.

In an ideal world, there would be a linear relationship between ATP and micro.”status”. Sadly this is not generally the case except in certain fortunate situations. Various previous attachments on this forum elaborate why.

 

Rgds / Charles.C

[fgjuadi]

Yes, my apologies as well, I also did not intend to hijack your thread Caz. 

 

I got the fundamental differnece between validation/verification (validate = make sure it happens, verify = make sure it is effective) - I possibly had a moment of not sober that influced that error post It's pretty embaressing cuz that's like QA 101, so I feel sufficeintly like an untrustworthy, overzealous moron now. 

 

I do take EMP E Bac swabs of food contact surfaces, considered salmonella & e coli but decided it was too risky on negative release...My problem there is that E bac levels don't correspond to any other levels, so they aren't the best indicator organisim.

 

So for a validation study, the steps in general would be :

 

1. Clean the equipment

2. Take an ATP swab

3. Take a sample with a method that tests for .. specific pathogens / microbes / "little guys" (Total coliforms, listeria, APC)?  Or just the thing you are trying to clean off (Chocolate test!  I guess for Caz in a dairy casein test?)

4.  Ideally, once you started seeing positive results that breach limits for your second test, the ATP test would be also above a certain level

 (For ex - Your spec limit is 5 horsepowers in Finished goods. You know if the surface has less than 5 horse powers, your FG will be in spec.  During your study, every time your 2nd test shows 5 horsepowers present on the surface, your ATP is always higher than 30, but when there are 4 horse powers present on the surface, ATP is only 25)

5. You set your limit at the ATP level highest that corresponds to the 2nd test still passing spec.

6. Caveat -  Turns out ATP levels don't actually correspond to anything, so if you do end up with results that make sense, take that lucky streak right on down to the bar and fill out a march madness bracket, then buy fancy $10 scratcher tickets.

 

OR -

"I take an ATP swab and a EMP swab every start up, and  every time I've had a hit on my EMP swab, ATP levels have been above #, so that number is my limit for pass/fail"

 

Back to off topic though - I understand that if you put sanitizer over something dirty it's only going to sanitize the surface of the dirt/bio film, which will be dispruted by turbulence during the process and be useless, so I can totally see the value of swabbing pre sanitizer to avoid false negatives or soaking your swab in a part that's still wet with sanitizer would give you false negatives.   What I don't understand is what the sanitizing step does afterward.  Do you clean, swab, sanitize, swab?  Like post clean and post sanitize are different limits because you're doing CIP, and they are totally separate steps in your process? (I do not envy the vigorus CIP cycles and tank holding limits of dairies)

[Charles.C]

Dear m_m,

 

validate = make sure it happens, verify = make sure it is effective

 

 

Actually, AFAIK (eg Codex), it's the exact reverse. (Not that I like the (older) Codex definition particularly.)

 

Maybe it depends on the resource.

 

And definitely no need to beat yourself up over it, every forum has pages of discussions over these terms, often due to endless mutual misunderstandings over the individual interpretation. And variations in textbooks / reference sources.

 

It's not iron-clad but one (chronological) separator is that validation is undertaken before the process is implemented (eg for routine use). verification takes place after routine use has started.

In practice, the validation timing tends to be "stretched", in the limit equating to an initial trial study.

 

From memory, NACMCF (1997) does a better job of explaining the terms than the original Codex. The later Codex has become somewhat of a standard reference, eg SQF (referenced then happily re-defined with an altered meaning!).

 

 

Re "OT" -

 

It's a question of terminologies again but (typically) for me -

 

Cleaning = application of a detergent chemical (particularly to expose the surface for the sanitizer but washing/cleaning can substantially reduce micro.populations also, sometimes more than the next stage)

 

Sanitizing = application of a microbiocidal chemical (targeted to "eliminate" microorganisms)

 

However there is a substantial dictionary to choose from. And a range of types of chemical actions for different scenarios.

 

Plus cleaning for "general" purposes is a rather different function as compared to an allergen -oriented activity

 

Rgds / Charles.C