APC tests
APC tests
(OP)
Dear All:
In my company as in all pharma sites, we have a Air Particle Counting monitoring program. For some time we are having some failures in rooms that puzzled me and consumed a great deal of my time (and company's money) trying to solve it. Recently, when again we were discussing this problem, a colleague of mine that is very experienced in this field, said a thing that surprised me:
She said that different brands of particle counters would give very different results in the particle counting. And we had that experience when we asked a subcontractor to makehte APC for us and its results were several times different than our own.
What I would like to ask is:
1-Did anybody experienced the same thing before?
2-how can we make engineering modifications based in results that are different depending on the machine that reads the APC?
Thanks a lot for you help.
PR
In my company as in all pharma sites, we have a Air Particle Counting monitoring program. For some time we are having some failures in rooms that puzzled me and consumed a great deal of my time (and company's money) trying to solve it. Recently, when again we were discussing this problem, a colleague of mine that is very experienced in this field, said a thing that surprised me:
She said that different brands of particle counters would give very different results in the particle counting. And we had that experience when we asked a subcontractor to makehte APC for us and its results were several times different than our own.
What I would like to ask is:
1-Did anybody experienced the same thing before?
2-how can we make engineering modifications based in results that are different depending on the machine that reads the APC?
Thanks a lot for you help.
PR





RE: APC tests
Generally you need not bother as long as the particle counters pass your area classification(though they show substantial difference in readings). Better is to follow the 14644 guidelines for sampling rate, sampling time and minimum no. of detectable particles.
Is your area failing with 0.5 micron particles are with bigger ones?
RE: APC tests
The particle is failing most on 0.5um but sometimes also fail bigger.
You say that it happens (the different result with different machines), but for me it is very difficult to understand that since big decisions are made over possible wrong data, like false results over the limit.
RE: APC tests
There are many variables involved in this process. Particles are not sperical always and these particle counters approximate them to the nearest diameter depending on the calculation fed into them. Even fibres and microorganism are approximated as particles. Water droplets also add difficulty to this process. It also depends upon the locations where you take particle count.
Check for particles at HEPA outlet to get some confidence about the counter. LAF stations are better places to check efficiency of the particle counters. If your areas are failing with big particles then clean the areas thoroughly. Check for dead pockets(particularly farthest points from the risers).
Good luck,
RE: APC tests