The human brain does not correctly intuit how to assess differences in efficiency when they are expressed as percentages.
If I just ask you: "what is twice as efficient as 90% efficiency?", you'll probably have to stop and think a bit before you come up with 95%. I suspect many people couldn't even come up with 95% as the correct answer.
If I asked you: what is 10x the efficiency of 90%, would you correctly come up with 99%? Even if you could, the process of answering that meant you had to overcome a mental block inside you telling you that 9% more than 90% cannot possibly be ten times better. It's only 9% better, right? And it's probably intuitive to nobody that ten times better than 99% efficiency is 99.9% efficiency. Our brains think in integer values and percentages are misleading.
This is a major advantage of using Beta Ratio instead of a percentage value. Anyone can intuit that doubling the efficiency of a ß100 gives a ß200 and because we used beta ratio, this intuition is correct! Beta ratio is just the upstream to downstream ratio of particles above some reference size cutoff. Just think of it as a "Particle Ratio" if you want to de-jargon it a bit (greek letters always sound pretentious to me)
In another active thread, someone mentioned the basic Microguard filter is rated 95% efficiency at 29 micron, which seems unimpressive. The M1-110EPs I use in my Honda are rated 99% at 30 micron. Similar rating right?
Well, no. The M1 is actually FIVE TIMES more efficient than the standard Microguard. If we convert the efficiency rating to Beta, we can clearly see this.
Microguard: 95% efficient. 100 particles go in, 5 come out. This is a ß20 filter at 29 Microns.
M1-110EP: 99% efficient. 100 particles go in, 1 comes out. This is a ß100 filter at 30 microns.
The M1 is 5x the efficiency of the MG basic at least if we ignore the micron rating associated with that efficiency. More on this momentarily.
What's more, when we have multiple filtration stages, beta ratio allows a simple multiplication to give a correct answer for total efficiency. If I have two ß100 (>30micron) filters in series, I'd have a cumulative beta of 10,000. It's intuitive AND correct.
Now-- what about that particle size rating? How much does it matter if its rated at 30 micron (M1) or 29 micron (MG basic) or 25 micron (MG Select) or 20 micron (Fram ultra).
This is actually quite a bit more important than people realize, because the effective beta ratio of a filter can shift radically with particle size.
I have worked with a fuel filter that has a published beta ratio of >1000 at >7 micron. But if you lower the cutoff to >6 micron, the beta drops to >100. if you raise the particle cutoff size to >14 micron, the beta ratio would be mind bogglingly large. How large? Well, to have a statistical certainty of a single particle of 14 microns making it through the media, you would need to pass through that media 941 million Olympic swimming pools full of fuel that meets Cummins specs for tank fuel cleanliness.
So with this filter, the Beta changes by an order of magnitude in a single micron, and in 7 microns it became a number so large that it has 20+ digits in the beta ratio.
I point this out because it's tempting to dismiss the small differences that really aren't small even in particle size. In reality, the Microguard's 95% at 29 micron and the M1s 99% at 30 micron might be nearly the same and it's possible that the Microguard might even be better! Yes, a single micron can matter. Now, 29 vs 30 is not nearly as big as 6 vs 7, but these are differences of degree and not of kind.
The key takeaways here are that small difference in efficiency and small differences in micron size aren't really small differences in real world efficiency. Especially once you account for multipass and total quantity of stuff removed over a drain interval. A couple microns of points of efficiency can end up mattering quite a bit.
If I just ask you: "what is twice as efficient as 90% efficiency?", you'll probably have to stop and think a bit before you come up with 95%. I suspect many people couldn't even come up with 95% as the correct answer.
If I asked you: what is 10x the efficiency of 90%, would you correctly come up with 99%? Even if you could, the process of answering that meant you had to overcome a mental block inside you telling you that 9% more than 90% cannot possibly be ten times better. It's only 9% better, right? And it's probably intuitive to nobody that ten times better than 99% efficiency is 99.9% efficiency. Our brains think in integer values and percentages are misleading.
This is a major advantage of using Beta Ratio instead of a percentage value. Anyone can intuit that doubling the efficiency of a ß100 gives a ß200 and because we used beta ratio, this intuition is correct! Beta ratio is just the upstream to downstream ratio of particles above some reference size cutoff. Just think of it as a "Particle Ratio" if you want to de-jargon it a bit (greek letters always sound pretentious to me)
In another active thread, someone mentioned the basic Microguard filter is rated 95% efficiency at 29 micron, which seems unimpressive. The M1-110EPs I use in my Honda are rated 99% at 30 micron. Similar rating right?
Well, no. The M1 is actually FIVE TIMES more efficient than the standard Microguard. If we convert the efficiency rating to Beta, we can clearly see this.
Microguard: 95% efficient. 100 particles go in, 5 come out. This is a ß20 filter at 29 Microns.
M1-110EP: 99% efficient. 100 particles go in, 1 comes out. This is a ß100 filter at 30 microns.
The M1 is 5x the efficiency of the MG basic at least if we ignore the micron rating associated with that efficiency. More on this momentarily.
What's more, when we have multiple filtration stages, beta ratio allows a simple multiplication to give a correct answer for total efficiency. If I have two ß100 (>30micron) filters in series, I'd have a cumulative beta of 10,000. It's intuitive AND correct.
Now-- what about that particle size rating? How much does it matter if its rated at 30 micron (M1) or 29 micron (MG basic) or 25 micron (MG Select) or 20 micron (Fram ultra).
This is actually quite a bit more important than people realize, because the effective beta ratio of a filter can shift radically with particle size.
I have worked with a fuel filter that has a published beta ratio of >1000 at >7 micron. But if you lower the cutoff to >6 micron, the beta drops to >100. if you raise the particle cutoff size to >14 micron, the beta ratio would be mind bogglingly large. How large? Well, to have a statistical certainty of a single particle of 14 microns making it through the media, you would need to pass through that media 941 million Olympic swimming pools full of fuel that meets Cummins specs for tank fuel cleanliness.
So with this filter, the Beta changes by an order of magnitude in a single micron, and in 7 microns it became a number so large that it has 20+ digits in the beta ratio.
I point this out because it's tempting to dismiss the small differences that really aren't small even in particle size. In reality, the Microguard's 95% at 29 micron and the M1s 99% at 30 micron might be nearly the same and it's possible that the Microguard might even be better! Yes, a single micron can matter. Now, 29 vs 30 is not nearly as big as 6 vs 7, but these are differences of degree and not of kind.
The key takeaways here are that small difference in efficiency and small differences in micron size aren't really small differences in real world efficiency. Especially once you account for multipass and total quantity of stuff removed over a drain interval. A couple microns of points of efficiency can end up mattering quite a bit.
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