When operated correctly BFS is arguably the most secure aseptic fill and finish process because of the closed parasol or rotary Blow-Fill-Seal machines.
It ensures there’s very little chance of the introduction of particles into the final container.
Particles can come from Upstream processes but generally with closed systems the chance of this is minimal.
Historical data on particles filled with Blow-Fill-Seal shows exceptional performance compared to Conventional systems
The polymer is not as clear as other materials so detecting particles especially in small volumes is very difficult.
The traditional way to look for them is to have humans to look at them under different lighting conditions and that’s used as the standard process.
The Blow-Fill-Seal is because it’s difficult to inspect.
Often more testing is required at the end product in terms of looking for samples of product and looking for particles in them.
Well the requirements either it’s 100 inspected Blow-Fill-Seal we will put them through the inspection process that not only looks for particles but for any cosmetic defects of the of the vial.
So they’re all 100 inspected but if the detection level for particles in Blow-Fill-Seal is quite low then a quality system will define how many samples are required for further testing in laboratory.
So human inspection has been the gold standard ever since filling of aseptic products has been done. It’s slow labor intensive and very expensive.
The use of machines has become much more common in large production facilities and the computer systems or vision systems are generally better than humans and when you come to qualify an automatic inspection machine you need to do a test with humans and then show that the machine is better than the humans in terms of detecting particles of different sizes.
It comes down to the particle sizes people can see quite large particles and they’re sort of up to you know a tenth of a millimeter in diameter but lower than that.
It’s very difficult to see machines. Vision systems can see smaller particles better than humans.