HACCP Standard: What Does It Mean for Your Magnetic Separator?
HACCP 0909MAGSEP 1-2010 International Food Safety Standard
If you have a magnetic separator in your food processing system or are considering adding one, have you wondered what kind of standards there are for your magnet? The food and dairy processing industries have so many standards and benchmarks, but what about magnetic separators?
HACCP: The Only Standard for Magnetic Separators
HACCP 0909MAGSEP 1-2010 is a standard that specifies requirements for final magnetic separation devices used to remove magnetic and weakly ferromagnetic particles from food product streams. The HACCP standard covers the requirements for materials of construction, fabrication and finishes, while assuring the magnet assembly is sanitary, cleanable and is designed to mitigate product contamination by preventing harboring of bacterial growth. Additionally, it specifies requirements for magnet strength, product coverage, and magnet circuit makeup to assure the magnetic separator will provide the highest efficiency in collecting and retaining ferrous contaminants.
Magnet Separator Efficiency
Processors should be aware that high gauss and high pull strength does not always equal an efficient and effective magnet, and that many magnets marketed to the food processing industry do not meet this standard. Let’s review a couple of the key factors that separate some high strength magnets on the market that don’t meet this standard with those that do.
Pole Spacing: Have you ever seen the inside of a typical round stainless steel bar magnet used in food processing magnetic separators? Inside of the thin wall stainless steel tube are many small cylindrical magnet cartridges, stacked end to end, with thin metal disks between them. The metal disks are called “pole plates”. The pole plates are where all of the magnetic flux lines are concentrated, and are the highest strength areas along the bar. Have you noticed that contaminants only collect on narrow bands along the magnet bar?
Those narrow bands are where the pole plates are located. To obtain very high holding strength some manufactures use longer magnet cartridges. This may give higher pull strength at the pole plates, but because the areas between those points have very little magnetic strength, it leaves a larger gap for small weakly magnetic particles like shavings to pass by without being caught. And with fewer pole plates within the same length bar it leaves less area for ferrous contaminants to collect. The HACCP 0909MAGSEP 1-2010 standard specifies a maximum pole spacing of 23mm for 18-35mm diameter bars. This means any standard 1” (24.5mm) bar magnet that has pole spacing over 23mm does not meet the requirements of this standard, and may not collect small weakly ferromagnetic particles efficiently.
Product Coverage: HACCP 0909MAGSEP 1-2010 requires that magnet separators provide 80% product coverage. This is defined as the proportion by volume of product contrived to contact the magnetic surface, or pass within 10mm of the magnetic surface. Magnet bars tend to have weak magnetic strength towards the ends of the bar. It is critical that product is directed to the higher strength main section of the bars and not allowed to flow directly over or past the bar ends. Magnet housings should be designed to shield these weak areas or deflect product across the strong areas. It is also critical that the bars are spaced properly to provide adequate coverage. It may be necessary to have multiple horizontal rows of bars to allow adequate spacing to prevent bridging and product blockages.
As you can see there is more to selecting magnetic separation devises for your food process than simply specifying Gauss or pull strength. To make sure your magnetic separator will provide the best possible performance you should ask “Does your magnet meet the HACCP 0909MAGSEP 1-2010 International Food Safety Standard?”
This standard can be purchased at https://haccp-international.com/standards/
Would you like to get your magnets validated by a certified service technician? PPS can help to arrange an on-site audit through our partners Magnattack™ and Active Magnetic Research.
