At medical device manufacturing facilities, controlling particles and fibers is a critical task as foreign material (FM) is a leading cause of reject and rework. Moreover, the inspection, cleaning and rework process are major drags on productivity.
Because FM is and always will be present, devices are most often assembled in ISO 7 and 8 clean rooms. These room classifications dictate a controlled level of contamination, but even when airborne counts are within specification, operators frequently come in contact with devices contaminated with fibers 100-500 micron in size.
Lets understand what happens at the workstation when inspection reveals that fibers are present on the device.
To begin with, the inspection process carried out by the operators and Quality Control staff is labor-intensive and by no means fool proof.
QC staff has designated three categories of FM contamination:
(1) Fully Embedded Fibers
Devices with fibers that are fully embedded in the coating or the component. These devices can either be immediately disregarded as scrap or may pass the quality requirements and manufacturing may proceed. Both conclusions are entirely based on the specific product and the FM requirements in place. Either way, it is out of the operator’s control.
(2) Loose Fibers
Loose fibers on the surface of the device may be removed with wipers, swabs or hand tools. Especially when hand tools are required this is very labor intensive and expensive process. It is not uncommon for operators to use wipers , swabs and hand tools to rework devices. Especially when hand tools are required this is very labor intensive and expensive process.
(3) Semi-Embedded Fibers
Fibers that are semi-embedded comprise the most difficult category of contamination. These are most frequently removed with tweezers and the removal process may lead to expensive scrap or rework, especially if coatings are involved.
It is easy to see that for many facilities, the steps taken to remove large fibers can significantly impact the cost of the device and the productivity of the facility. Please stay tuned for future articles that discuss root cause solutions or contact us if you would like more information to reduce contamination related defects and rework