By Paolo Scalisi

Frequently employed in the automotive industry, among others, the eight disciplines problem solving (8D) methodology is a quality practice aimed at product and process improvement that can help medical device manufacturers effectively address complex packaging issues. The goal of the eight-step process is to develop proper actions in order to eliminate root causes of failure in the production process. Moreover, the primary objective of this quality tool is to implement permanent corrective actions to avoid recurrence of the failure. 

The Basics of 8D
The 8 disciplines in the process are:

Several steps in the 8D methodology require more detailed explanation in the context of tackling a complex medical packaging problem: 

Containment action: This is a responsive action that immediately stops the defective medical packages from reaching the customer and replaces the potentially defective packages with packages from a verified lot.

Root cause: This term encompasses all of the conditions and events that may result in the failure of process outputs. A high volume of package returns or problems may indicate a material defect or flawed assembly process. Determining the root cause requires analysis of whether the defect is present when different machines are used for assembly, which may indicate reliability issues, and the different materials that comprise the medical package.

In the case of returns attributed to a corrupted substance, for example: If the substance is contained in medical packages produced by an old production line, the root cause is likely due to a defect in the calibration of the assembly machinery. 

If the same defective packages were produced by a new production line that uses new materials and production thermal chambers, however, the root cause is probably due to either nonconformity of the raw materials used for assembly or contamination of the chambers.

Corrective action: This is an action implemented with the intent to fix the root cause of a problem. To do so, the team must identify the point of failure in the production chain for the medical packages from the defective lot.  

Benefits of 8D
Among the strengths of this problem-solving strategy is that it is oriented to the zero-defects condition and identifies the exact step of the production process that yielded the problem. Determining the root cause in order to eliminate recurring defects is considered the best approach to solving some critical medical packaging or other product problems. 

Training and appropriate tools are required in order to leverage the 8D process for medical packaging quality issues. Ultimately, however, the 8D process can be effectively applied to many packaging problems, quality returns, or recalls that may arise. 

Paolo Scalisi is a senior test product engineer at STMicroelectronics Italy.