As the container is made, filled and sealed within a single machine and the process is protected using a sterile air shower and additionally, all process media (solution, air etc.) are sterile filtered, the chance of contamination is very remote. Adding to the fact that during the whole cycle, open containers remain exposed to the clean room air for less than 1.5 seconds, the Blow-Fill-Seal technology becomes the process of choice where contamination of particle matter and microbial contamination is a primary concern.

Flexibility in choice of packaging material
Primary Packaging (or the container) protects pharmaceutical ingredients from environmental contaminants, micro-organisms, as well as particulate material. The container also protects active ingredients and/or excipients from getting out due to diffusion and thus providing stability to the product. It can also protect the content from light and can act as a barrier to protect the content from environmental gases.
Another aspect to be kept in consideration is that the additives in the plastic container can leach into the solution.
Pharmacopoeia has set limits on the content of the additives in plastic containers for drug products. It has also specified the types of additives which are not allowed in plastic material destined for making primary containers for packaging of pharmaceutical products.Several leading manufacturers today produce Polypropylene, as well as Polyethylene approved for making containers for intravenous and injectable applications.
Although the final package is sterile after the BFS process, Good Manufacturing Practice (GMP) in some countries and Pharmacopoeia in the United States and European Union still impose terminal sterilization for products which can sustain steam sterilization. In fact, the European Medicinal product Evaluation Agency (EMEA) goes to extent of recommending that manufacturers should search for suitable packaging material which allow terminal sterilization at preferred temperatures within a limited time frame.
Due to the above considerations, a BFS machine, which has capability to process and make containers out of a wide range of material (low density polyethylene, high density polyethylene, polypropylene), is preferred in the pharmaceutical industry.