When many customers first use dust particle counter to detect the cleanliness level of dust-free workshop, the test results cannot determine the cleanliness level of the area, or there are some doubts about the test results. The following is a brief introduction to the cleanroom cleanliness level judgment standard and conversion method. First, we need to understand it from the formula:

1 cubic meter = 1000L (Metric);

1 cubic foot (1CFM) = 28.3L (Imperial);

0.1CFM=2.83L

1000L/2.83L=352;1000L/28.3L=35.2;1000L/50L=20;1000L/100L=10.

The definition of clean room grade is:one cubic foot, look at the number of 0.5um particles, for example, the thousandth grade means that there are no more than 1000 0.5UM particles in one cubic foot (within 1000), and the ten thousandth grade means that there are no more than 10000 0.5UM particles in one cubic foot (within 10000). However, one cubic foot = 28.3L, so if you are using a 2.83L handheld dust particle counter, the result of the detection must be * 10. For example, if the number of 0.5UM particles detected by the 2.83L instrument (TSI9303 or 9306-04 dust particle counter) is 518, then the result is:518*10=5180, which is more than one thousand, so the workshop grade is ten thousand.

If you are using a 28.3L large flow instrument, the result does not need to be *10. Because 1 cubic foot (1CFM) = 28.3L (Imperial);if it is a 50L instrument, the result should be *1.77;if it is a 100L instrument, the result should be *3.54.
 

If we look at the grades according to the ISO14644 purification standard table, ISO grade 5 is grade 100, ISO grade 6 is grade 1,000, and ISO grade 7 is grade 10,000.

1 cubic meter = 1000L (metric system), 1000L/2.83L=352;1000L/28.3L=35.2;1000L/50L=20;1000L/100L=10.

If using 2.83L instrument for detection, the result needs to be *352. For example, 0.5UM detects 17, which is 17*352=5984. Compared with ISO 14644 international purification standard, it is grade 1000 (ISO5, 0.5UM:3520;ISO6, 0.5UM:35200).

If a 28.3L instrument is used for testing, the result needs to be *35.2;

If a 50L instrument is used for testing, the result needs to be *20;

If a 100L instrument is used for testing, the result needs to be *10.

The above is a brief introduction to the cleanliness level judgment standard and conversion method.