How automated monitoring systems can increase contamination protection and save you time and money.

MOST OF US HAVE EXPERIENCED being in a barn on a sunny day with the sun penetrating the wooden slats and the small light speckles reflecting the sunlight and moving all around us. Looking at the shaded areas the small light speckles are not visible. The reason is that the particles in the shade are unable to reflect the sunlight penetrating the slats and for that reason we do not see them. We breathe in millions of particles everyday. Our immune system is able to combat 99% of the particles we inhale with the exception of some bacteria andviruses.

Inside a cleanroom, the environment is controlled using high efficiency particle air filters, more commonly known as HEPA filters. Depending on the classification of the cleanroom, the number of air changes per hour increases or decreases. That environment is tested and classified based on the validation work carriedout.

So when a cleanroom is built, it reaches its highest classification before the process equipment or operators are introduced. With the introduction of process equipment and operators, the levels of particles entering the cleanroom rise. Gowning up and the use of smooth surfaces on process equipment reduce the build up of particles but equipment with moving parts and the operators still generate a considerable amount of particles. Independent tests show that the average human generates about 500,000 particles/minute. That figure reduces by gowning up but particles are still generated. Sources of contamination may include; dead skin and hair, cosmetics and clothing, bacteria, an addition of a new contaminated product, or ingression from operating environment.

It is critical that sterile environments are particle free. Consider a drug manufacturer whose product is administered to patients intravenously. The most critical point during the process of the final product is the filling and capping. Viable particles should be non-existent in these areas; otherwise the patient’s health is at risk as his or her already low immune system may not be able to effectively combat contaminated medicine. Also, if the particle is big enough it may block veins or capillaries. These are just some of the reasons why this type of industry and product are heavily regulated by bodies such as the FDA (Food and Drug Administration) and the EC (European Commission).

How do we fight a battle when we cannot see what we are trying to eliminate? Particle counters and air samplers are used to monitor cleanrooms. Particle counters detect the size and concentration of particles present. Air samplers detect what types of particles are present.