How do an Engineering Change Proposal (ECP) and a Request for Variance (RFV) differ?

The distinction between an Engineering Change Proposal (ECP) and a Request for Variance (RFV) is rooted in the permanence of the changes they represent. An ECP is a formal proposal initiated to implement a change in specifications, designs, or processes, and is intended to be a permanent modification once approved. This means that the change will be integrated into the documentation and the product or system moving forward.

In contrast, an RFV is typically used to request a temporary departure from established requirements or standards, often due to unexpected conditions or situations that arise during the manufacturing or operational phases. The intention behind an RFV is generally to address a specific problem or constraint without permanently altering the baseline specifications or designs.

Thus, identifying the permanence of the ECP as a foundation for sustained changes and the temporary nature of the RFV clarifies their fundamental differences, reinforcing why the characterization of an ECP as permanent and an RFV as temporary is correct.