I'm sure blackstone did a good job doing the count.
Changing the air filter or not impacts the dirt that gets into the oil.
In order for testing to be more accurate, imho, the air filter needs to have the same service life on it. Because normal oil analysis shows the longer you run an air filter the lower the silicon ( dirt) counts go. A new air filter will allow more dirt through. So the second test when the new air filter was used, should show higher particle counts regardless of filter used. And the first test might be skewed because the air filter was nearer it's service life.
If you really wanted comparable testing use one new air filter and the same oil filter brand for the three tests. Then change the air filter and use the second brand for three tests. Then compare. That would be a slightly more accurate comparision.
Just like one oil sample doesn't really tell you much. It is thru multiple sample testing where the comparisons show a better value.
But that was a good start.
Changing the air filter or not impacts the dirt that gets into the oil.
In order for testing to be more accurate, imho, the air filter needs to have the same service life on it. Because normal oil analysis shows the longer you run an air filter the lower the silicon ( dirt) counts go. A new air filter will allow more dirt through. So the second test when the new air filter was used, should show higher particle counts regardless of filter used. And the first test might be skewed because the air filter was nearer it's service life.
If you really wanted comparable testing use one new air filter and the same oil filter brand for the three tests. Then change the air filter and use the second brand for three tests. Then compare. That would be a slightly more accurate comparision.
Just like one oil sample doesn't really tell you much. It is thru multiple sample testing where the comparisons show a better value.
But that was a good start.