Validation of critical limits for Magnets and Sieving

Hi guys,

  We installed vibro sifter and magnetic trap after one another at each line of finished products just before the packing silos in a flour mill. I really need helps regarding on how to set critical limits and how to validate these limits. Normally no metal piece in finished product is set as a critical limit now.

secondly we want to set the critical limit for metal dust. We did check on the weight of metal dust collected from the magnet on daily basis, but just for record without any critical limit. I would like to set a limit for this. 

Can any kind souls help me and give your opinion on this please

Regards & Thanks

Muhammad Akhlaq

Hi, Makhlaq.

Please see link.

https://www.ifsqn.co...reens-as-oprps/

Basically, no critical limit if you categorize it as not CCP on your HACCP study. I usually does not favor "dust" or "weights" for magnets without relative dimension, or do you mean you establish a "baseline" for magnet collection for dust?

Hi, Makhlaq.

 

Please see link.

 

 

https://www.ifsqn.co...reens-as-oprps/

 

Basically, no critical limit if you categorize it as not CCP on your HACCP study. I usually does not favor "dust" or "weights" for magnets without relative dimension, or do you mean you establish a "baseline" for magnet collection for dust

Hi, 

Vibro sifter and magnets both are declared as CCPs in HACCP study, they collectively cover iron and non iron metal pieces contamination. Sieve size in vibro sifter is 425 and 390 microns.

Here food safety auditors consider iron dust as contaminants and ask about its control measure.   

Yes, it is a contaminant but what reference do they use for the dust as hazard? Just to add, to ensure that your sieve is magnetizable. Otherwise, installing magnet after sieve will not provide you added benefits given your sifter mesh size.

Have provided the link in the how for the normal validation of sifter and magnet. My problem for the dust is consider the following picture.

If example you pass in the magnet 100g of "dust" and you only recover 99.5.. is the 0.5% will still consider you safe?  Can it be provided in the products as PPM just to say it is still okay? That is why, in my opinion, it is really difficult to have the dust or weight as basis. Normally, widely available references have it as strength and pass through the normal contaminant. What I have observed in some is that they have a baseline for about 2weeks-1month on the weight they recover in magnet. (they have this analyze though) and have it as baseline. If they exceed this baseline then investigation is warranted. They added as well some quantitative size for example if they found 1mm shiny metal.

Btw, what product do you produce? Sometimes, charred organic material and salts are also being caught by magnet. For why, I do not know. :)

Also one thing to add but this one still depend on how organization answer the decision tree, in my case or in our case we challenge the notion if vibra sifter really eliminate or reduce to acceptable level the hazard is, if you think of the "worst case scenario" if there will be example wire with a thickness of 0.4mm and length of say 7-8mm and have sharp edges, what if this one pass through perpendicular through the opening of the sieve, will we say the CCP does not work or the HACCP fail to identify the possibility of this hazard going through. It is this case our team challenge it being CCP in most cases, but then again, it depends on the team's HACCP study and the confidence with the team's HACCP study :)

Validate by inserting the actual contaminant inside a marked product/batch. The size of the contaminant should be equivalent to your CCL. If this is detected (sieved/excluded/filtered) then your control method is validated.

Please also take into consideration that when you made your risk analysis, you considered severity of the effects. if your risk rating is low, this doesn't have to be a CCP.