Isolators provide a barrier between the product and the operator and the environment. They are designed to protect the product, the operator or both. There are a variety of designs and are quite often one-off designs for a particular purpose. Because of this and because of the high standard of control required, they are relatively expensive when compared to conventional cabinets.
Some designs have a minimal airflow, where particulate level control in the sense of cleanroom technology is not a consideration. Other designs utilise unidirectional airflow to control particulate levels to very low levels. All the air entering an isolator is ULPA filtered.
Isolators are tested to prove the integrity of the filters, the air velocity and uniformity where applicable and the integrity of the cabinet itself.