Q: I work for a consumer products company where more than 60% of our products have a visual fill requirement. This means, aside from meeting label claim, we must ensure the fill level meets a visual level.
What is the industry standard for visual fills?
We just launched Statistical Process Control (SPC), and we notice that our products requiring visual fills show significant variability.
A: This is an interesting question. The NIST SP 1020-2 Consumer Package Labeling Guide and the Fair Packaging and Labeling Act, along with any other industry standards, regulate how you must label a product “accurately.” However, it appears you have been burdened with a separate, and somewhat conflicting requirement — a visual fill requirement.
In most cases, you probably cannot satisfy both requirements without variability. The laws and standards will direct labeling requirements with regard to accuracy, and your company is liable for that. If you choose to use visual fill standards for “in-process” quality assurance, then you would need a fairly broad range between the upper and lower acceptance limits.
Personally, I would use weights and measures as needed to meet customer and legal requirements. These are the data I would use for SPC records.
If your company has a need (or a desire) to use visual fill levels for a gage, then generating a work instruction telling employees where a caution level is would be a way to start. In other words, “If the visual level is above point A or below point B, immediately notify management.” If you are to remain compliant with what you put on a label, visuals will change from run to run. Using them as a guide for production personnel can be a helpful tool, but not as a viable SPC input.
ASQ Senior Member, CQT, CQI
Editor’s Pick: Hear how Procter & Gamble developed a solution for setting appropriate targets for product filling processes in Setting Appropriate Fill Weight Targets—A Statistical Engineering Case Study from the April 2012 Issue of Quality Engineering.