Jump to content

  • Quick Navigation
Photo

Magnets-Metal dust critical limit

Share this

Best Answer , 20 November 2021 - 05:45 PM

Magnets are a poor CCP (if that is what you are stating).   I have seen one validation study that is next to impossible to achieve.  Plus the issue that you have.  as usual Charles is on the money.   

 

In general, the magnet is metal detection and removal /tool.   It helps identify possible FM issues in the plant.  As such, you should examine (as you are) and take actions on adverse findings (which you are not).  

 

You could deem dust to be acceptable and not require investigation (if this makes sense with your equipment).   Or set a limit as to the amount that requires investigation/capa.   It may be that any dust requires a investigation & capa. 

Pieces that could be considered a food safety risk (wires, pieces larger than "X", pieces that indicated equipment failure) would always require a investigation and corrective / preventative actions.  These are just examples of things I have seen or done.   You will have to determine what makes sense for your operation.   

 

Strength of magnets should be checked annually (gauss or pull strength test) to ensure they remain effective.   

Dear, your answer  is what I was searching for, what is acceptable, what is not. 

Metal dust is acceptable. Larger pieces, bigger amount of dust than usually or wires-not acceptable (needs corrective actions). For me now is more clear. Thank you very much for your help. 


  • You cannot start a new topic
  • Please log in to reply
10 replies to this topic

Ligita012

    Grade - Active

  • IFSQN Active
  • 5 posts
  • 0 thanks
1
Neutral

  • Lithuania
    Lithuania

Posted 12 November 2021 - 07:07 PM

Hello,

We have  magnets in our milk powder production line. We do check it daily, and collect the findings. Sometimes there are more fine dust, sometimes less. Sometimes there are a bit bigger metal pieces. We collect it but just for record without any critical limit or risk analysis. 

Auditor suggested to write is it acceptable or no? maybe to have classes A,B,C. 

Can anybody help me how to define these limits?

We also have metal detector at the end of the line.

 

Your help would be very appreciated.

 


  • 0

SQFconsultant

    SQFconsultant

  • IFSQN Fellow
  • 4,970 posts
  • 1194 thanks
1,232
Excellent

  • United States
    United States
  • Gender:Male
  • Interests:Home now on Martha's Vineyard Island/Republic of these United States

Posted 14 November 2021 - 10:35 AM

I can not attest to the limits,but this would be a failure in my eyes to not rca and record actions taken.


  • 1

All the Best,

 

All Rights Reserved,

Without Prejudice,

Glenn Oster.

 

Glenn Oster Consulting, LLC

-SQF System Development, Implementation & Certification /Internal Auditor Training /eConsultant Retainer

 

Now also serving the states of Australia, Canada & Mexico

 

Oak Bluffs, Martha's Vineyard Island, Massachusetts

Republic of these United States (restored)
 

www.GlennOster.com | 774.563.6161 | glenn@glennoster.com 
 

 

 

 


Thanked by 1 Member:

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 20,542 posts
  • 5683 thanks
1,550
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 14 November 2021 - 02:05 PM

Hello,

We have  magnets in our milk powder production line. We do check it daily, and collect the findings. Sometimes there are more fine dust, sometimes less. Sometimes there are a bit bigger metal pieces. We collect it but just for record without any critical limit or risk analysis. 

Auditor suggested to write is it acceptable or no? maybe to have classes A,B,C. 

Can anybody help me how to define these limits?

We also have metal detector at the end of the line.

 

Your help would be very appreciated.

Hi Ligita,

 

It is possible that Lithuania has Regulatory requirements for yr query (assuming local consumption).

 

The CCP/critical limit is most commonly (but not 100% exclusively) limited to the metal detector (MD).

 

A few countries have defined maximum metal contaminant limits for RTE items based on a haccp/hazard type interpretation, eg Canada has maximum 2mm for non-sensitive consumers (eg not infants).

 

Milk not my area of expertise but for typical RTE food products, the ideal objective of equipment you mention is to achieve zero detectable metal contamination of final product.

 

A generic answer to yr query is that the critical limit can be defined as the limit of detection (LOD) (ie sensitivity) of MD for a specific metal(s) (typically ferrous iron, non-ferrous iron, stainless steel) which will vary with factors such as food matrix, MD aperture, container presentation, etc.

 

I daresay you are already validating MD performance via standard test pieces ?

 

As one example, can have a look at the MD section in this model haccp plan  -

 

Attached File  CFIA - HACCP Generic Model for Fresh produce, Ready-To-Eat Fresh-Cut Vegetables.pdf   427.08KB   58 downloads


  • 0

Kind Regards,

 

Charles.C


Thanked by 2 Members:

kingstudruler1

    Grade - PIFSQN

  • IFSQN Principal
  • 993 posts
  • 323 thanks
322
Excellent

  • United States
    United States

Posted 16 November 2021 - 06:51 AM

Magnets are a poor CCP (if that is what you are stating).   I have seen one validation study that is next to impossible to achieve.  Plus the issue that you have.  as usual Charles is on the money.   

 

In general, the magnet is metal detection and removal /tool.   It helps identify possible FM issues in the plant.  As such, you should examine (as you are) and take actions on adverse findings (which you are not).  

 

You could deem dust to be acceptable and not require investigation (if this makes sense with your equipment).   Or set a limit as to the amount that requires investigation/capa.   It may be that any dust requires a investigation & capa. 

Pieces that could be considered a food safety risk (wires, pieces larger than "X", pieces that indicated equipment failure) would always require a investigation and corrective / preventative actions.  These are just examples of things I have seen or done.   You will have to determine what makes sense for your operation.   

 

Strength of magnets should be checked annually (gauss or pull strength test) to ensure they remain effective.   


  • 1

eb2fee_785dceddab034fa1a30dd80c7e21f1d7~

    Twofishfs@gmail.com

 


Thanked by 1 Member:

Ligita012

    Grade - Active

  • IFSQN Active
  • 5 posts
  • 0 thanks
1
Neutral

  • Lithuania
    Lithuania

Posted 20 November 2021 - 05:45 PM   Best Answer

Magnets are a poor CCP (if that is what you are stating).   I have seen one validation study that is next to impossible to achieve.  Plus the issue that you have.  as usual Charles is on the money.   

 

In general, the magnet is metal detection and removal /tool.   It helps identify possible FM issues in the plant.  As such, you should examine (as you are) and take actions on adverse findings (which you are not).  

 

You could deem dust to be acceptable and not require investigation (if this makes sense with your equipment).   Or set a limit as to the amount that requires investigation/capa.   It may be that any dust requires a investigation & capa. 

Pieces that could be considered a food safety risk (wires, pieces larger than "X", pieces that indicated equipment failure) would always require a investigation and corrective / preventative actions.  These are just examples of things I have seen or done.   You will have to determine what makes sense for your operation.   

 

Strength of magnets should be checked annually (gauss or pull strength test) to ensure they remain effective.   

Dear, your answer  is what I was searching for, what is acceptable, what is not. 

Metal dust is acceptable. Larger pieces, bigger amount of dust than usually or wires-not acceptable (needs corrective actions). For me now is more clear. Thank you very much for your help. 


  • 1

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 20,542 posts
  • 5683 thanks
1,550
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 21 November 2021 - 12:23 PM

Dear, your answer  is what I was searching for, what is acceptable, what is not. 

Metal dust is acceptable. Larger pieces, bigger amount of dust than usually or wires-not acceptable (needs corrective actions). For me now is more clear. Thank you very much for your help. 

Hi Ligita,

 

It may not be necessary to risk categorize items adhered to the magnet. IMO the capture of "large" quantities of magnetic extraneous material of any variety justifies some investigation as to the source. However attempting to risk categorize the debris creates another (highly debatable) topic to be audited on.

 

Below is attached a rather elegant haccp plan containing magnets and metal detector, the latter defined as CCP. So the only haccp-specific corrective actions are those associated with the metal detector. Note the hazard specified as potentially associated with the magnet process step. The only questionable aspect of this analysis afaik might be that in respect to dust, the magnet might be more sensitive than the MD. For example see this earlier comment -

https://www.ifsqn.co...ccp/#entry35434

However I doubt very much that an auditor will challenge you to this degree of fine detail. :smile:

 

JFI there are numerous other threads on this complicated topic which may interest you, eg -

 

https://www.ifsqn.co...on/#entry143491

 

Attached File  HACCP Plan RTE Spices, CFIA.pdf   2.18MB   91 downloads


  • 1

Kind Regards,

 

Charles.C


Thanked by 1 Member:

kingstudruler1

    Grade - PIFSQN

  • IFSQN Principal
  • 993 posts
  • 323 thanks
322
Excellent

  • United States
    United States

Posted 22 November 2021 - 06:01 PM

Hi Ligita,

 

It may not be necessary to risk categorize items adhered to the magnet. IMO the capture of "large" quantities of magnetic extraneous material of any variety justifies some investigation as to the source. However attempting to risk categorize the debris creates another (highly debatable) topic to be audited on.

 

Below is attached a rather elegant haccp plan containing magnets and metal detector, the latter defined as CCP. So the only haccp-specific corrective actions are those associated with the metal detector. Note the hazard specified as potentially associated with the magnet process step. The only questionable aspect of this analysis afaik might be that in respect to dust, the magnet might be more sensitive than the MD. For example see this earlier comment -

https://www.ifsqn.co...ccp/#entry35434

However I doubt very much that an auditor will challenge you to this degree of fine detail. :smile:

 

JFI there are numerous other threads on this complicated topic which may interest you, eg -

 

https://www.ifsqn.co...on/#entry143491

 

attachicon.gif HACCP Plan RTE Spices, CFIA.pdf

Charles is correct.   I tried to give examples but I didn't want you or anyone else to take them as gospel.  which is why I used words like "could" or "May".  

 

Hopefully, if you never had dust on a magnet and then see 100 grams, that would tell you that something is wrong in the system and needs investigation.   In this case, that "dust" probably  would not be acceptable.  It could be that "dust' is not acceptable in your operation as well.       

 

You need to develop the limits that make sense for your facility.     


  • 0

eb2fee_785dceddab034fa1a30dd80c7e21f1d7~

    Twofishfs@gmail.com

 


PQEdwards

    Grade - AIFSQN

  • IFSQN Associate
  • 31 posts
  • 2 thanks
4
Neutral

  • United Kingdom
    United Kingdom

Posted 26 November 2021 - 08:35 AM

Dear, your answer  is what I was searching for, what is acceptable, what is not. 

Metal dust is acceptable. Larger pieces, bigger amount of dust than usually or wires-not acceptable (needs corrective actions). For me now is more clear. Thank you very much for your help. 

Exactly the approach we take with our food ingredient which also a fine powder. We based the powder limits based on the historical norm and the size of particle based on potential for harm and investigate when these limits are not met. Some production lines it is not possible to install metal detector so magnet our best line of defence.


  • 0

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 20,542 posts
  • 5683 thanks
1,550
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 26 November 2021 - 11:06 AM

Exactly the approach we take with our food ingredient which also a fine powder. We based the powder limits based on the historical norm and the size of particle based on potential for harm and investigate when these limits are not met. Some production lines it is not possible to install metal detector so magnet our best line of defence.

 

Hi PQE,

 

Thks for Input.

 

The US historical incidence of recalls based on presence of metallic dust (= adulteration) may rebut this as a General approach. Although I daresay UK's viewpoint on adulteration may differ.

 

Nonetheless, this Procedure is apparently also utilised by Kraft so I guess the Practicality (ie no MD) depends on Validation/Type of Product Input/Efficiency of Magnet and (acceptable/historical)  Risk. I have no direct magnet experience but this approach certainly "looks" easier to routinely implement as compared to monitoring Magnet strength.

 

PS -  What do you define as a harmful particle size ? ( I speculate that  the OP's process would generate a significant volume of corrective actions :smile:)

.

PPS - JFI note that the last attachment in this parallel Post opines that a Validation Study is not feasible for this kind of CL -

 

https://www.ifsqn.co...ps/#entry180736


  • 0

Kind Regards,

 

Charles.C


PQEdwards

    Grade - AIFSQN

  • IFSQN Associate
  • 31 posts
  • 2 thanks
4
Neutral

  • United Kingdom
    United Kingdom

Posted 26 November 2021 - 12:52 PM

Hi PQE,

 

Thks for Input.

 

The US historical incidence of recalls based on presence of metallic dust (= adulteration) may rebut this as a General approach. Although I daresay UK's viewpoint on adulteration may differ.

 

Nonetheless, this Procedure is apparently also utilised by Kraft so I guess the Practicality (ie no MD) depends on Validation/Type of Product Input/Efficiency of Magnet and (acceptable/historical)  Risk. I have no direct magnet experience but this approach certainly "looks" easier to routinely implement as compared to monitoring Magnet strength.

 

PS -  What do you define as a harmful particle size ? ( I speculate that  the OP's process would generate a significant volume of corrective actions :smile:)

.

Hi Charles,

 

Also thanks for the input

 

As you indicate it's all about context and position within food chain. In some processes metallic fines (my definition of fines is <<1mm) are technically unavoidable due to the abrasive nature of the material and the process involved (e.g. milling, grinding), whilst equipment design and maintenance help minimise magnets can offer a effective method of reduction to acceptable levels.

 

Establishing warning and action limits based on statistical analysis of historic levels removed during production of "acceptable" product helps identify when the process is moving out of control and excessive contamination is a possibility. Ultimately the often quoted FDA guidance document helps define harmful size but the end use and customer feedback will probably lead you to lower sizes.

 

Validation by checking the strength of magnets routinely against the design strength goes without saying.

 

Anyway that's the approach my team has taken and enabled us to achieve certification to a GFSI approved scheme, so I am reasonably content about that the approach can be robustness in some cases. 


  • 0

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 20,542 posts
  • 5683 thanks
1,550
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 27 November 2021 - 07:02 PM

Hello,

We have  magnets in our milk powder production line. We do check it daily, and collect the findings. Sometimes there are more fine dust, sometimes less. Sometimes there are a bit bigger metal pieces. We collect it but just for record without any critical limit or risk analysis. 

Auditor suggested to write is it acceptable or no? maybe to have classes A,B,C. 

Can anybody help me how to define these limits?

We also have metal detector at the end of the line.

 

Your help would be very appreciated.

 

Hi Ligita,

 

IIRC, a simple answer from a safety POV is that, Based on Canadian Regulatory Guidelines for a non-vulnerable (eg not an infant) consumer, hard, sharp metal particles >=2mm in any dimension found in RTE foods are considered to create a high risk situation. If a vulnerable consumer exists the value  changes to >0 mm.

 

Validation of the CL of a solitary magnet if categorized as a CCP is discussed at some length in this thread although I found the content rather confusing.

https://www.ifsqn.co...ng/#entry131756

 

Of course, the MD will hopefully capture any metal contamination which escapes the magnet


  • 1

Kind Regards,

 

Charles.C




Share this

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users