Category: Quality Control

Which AQL do you choose?

One of the most frequent questions we receive regarding on-site quality inspections relates to selecting AQLs, or Acceptable Quality Levels.  AQLs represent the maximum percent defective that you consider acceptable.

Pro QC’s Assistant Operations Manager in China, Cesar Marsical, address the question below:

The selection of AQLs and sampling plan for a given lot size depends on too many factors to permit the issuance of a “pre-selected” standard set of plans for specified lots. Each user should select AQLs and sampling plans that are tailored to best meet their needs.  Pro QC can assist with this process.

Some of the factors that must be considered prior to selecting the AQLs are:

1) Classifications or categories of defects such as Critical, Major and Minor – Critical defects would generally require zero defects, which means the highest AQL value should be imposed.  Major defects would generally require a lower AQL than those for minor defects.

2) Process capabilities under good commercial practice with respect to the defects in question – For example, if under normal production process, the defect levels cannot be kept below 2.0 percent defective, the selection of an AQL of 0.15 percent defective, although desirable for the defects in question, may not be practical.

3) Consumer preferences – These may require higher AQL’s or permit lower AQL’s than process capabilities would indicate.

4) Time and cost required to sample and inspect a lot under various AQLs – The smaller the AQL, the more time and cost of inspection.

Some of the factors that may be considered prior to selecting the sampling plans for a given lot size includes:

1) The applicable AQLs – The AQL dictates, among other things, the smallest sample size that can be used and the size of the “jumps” from one sample size to the next larger one.

2) The relative ability of the plans to discriminate between “good” and “bad” lots. – Although several plans in these standards have the same AQL, they differ in their ability to reject lots worse than the AQL’s. The OC (Operating Characteristics) curve in the standards of this subpart provides the basis for determining the discriminating ability of each plan.

3) The amount, time, and cost of sampling required.

4) The size and value of the lots relative to the producer and consumer protection a sampling plan affords.  One may be willing to take larger risks of passing “bad” lots that are small or of lesser value than they would for larger more valuable lots.

5) The knowledge about the lot(s) to be submitted for inspection – Lots consisting of product produced under essentially the same conditions may require smaller sample size than those consisting of product produced by different shifts and different raw stocks for example.

6) The record of the quality level of previously submitted lots – The sample size can be smaller for lots submitted from a supplier with a consistent record of quality levels significantly better than the specified AQL(s) than sample sizes for the supplier whose records shows considerable variability in quality, “borderline” supplies or products worse than the AQL.

Based on the above, decide what quality levels you are willing to live with and what quality level that you are not willing to live with.

Contact us for more info, or assistance with this process.


7 QC Tools in 8 Minutes

Great presentation… Quick and easy way to learn about quality control, the benefits and the primary tools used in the industry.

  • Graphs
  • Check Sheets
  • Pareto Charts
  • Cause & Effect
  • Scatter Diagrams
  • Histograms
  • Control Charts

In addition, we discuss the benefits of quality control on our website .  We also talk quality tools in a few older blog posts.  And, we’ve written a few articles in our newsletter as well.

Top 5 Quick & Invaluable Quality Reads for 2013

A thread in the ASQ LinkedIn group piqued our interest a few months back.  It got us thinking about our favorite quality related books and provided some excellent insight into a few we haven’t read yet.

We know life is busy, but we all know the importance of continuous improvement   Our list of quick and invaluable quality related “must read” books includes:

The Daily Drucker: 365 Days of Insight & Motivation for Getting the Right Things Done (Peter F. Drucker)  – This little gem is a quick and easy way to start the day thinking in a quality mindset.  More than a few great ideas and inspiration came from this one, and it can be used more than once.

The Five Most Important Questions (Peter F. Drucker) – This is a very quick read, perfect for a short flight.  In it, Drucker discusses self-assessment, the customer, providing value, measuring results and planning.  This one is likely to require “pen and paper” or Evernote to get the full benefit.  You’ll want to document your answers.

Quality Improvement Made Simple & Fast (Matthew J. Maio) – We have done a write-up on this book before and continue to highly recommend it.  While the length, only a 44 page booklet, may be deceiving, the content is rich and ready to be applied.  This book will guide you through Plan>Do>Study>Act and is written in a way that’s fun to read.  The templates in the back are invaluable.

The Quality Toolbox (Nancy R. Tague) – This book should be standard reading in college courses and a staple on any business person’s bookshelf.  In it, you will find a way to answer any question (or problem) you have.  It gives you the tools you need to get stuff done.  Rather than trying to read it cover-to-cover, this one works best if you make a goal of reviewing one tool per week.  There’s even a chapter on “How to Use this Book.” 

101 Good Ideas: How to Improve Just About Any Process (Karen Bemowski & Brad Stratton) – This book is conveniently segmented in a way that lets you skip around and pick what you want to learn.  It offers examples and tools for improving a process, communicating quality, training for quality, getting feedback, managing meetings organizing/analyzing data, auditing and more.  The ideas presented are general in nature, but provide enough information to get you going in the right direction.

“The more that you read, the more things you will know. The more that you learn, the more places you’ll go.”  ~Dr. Seuss

“It is what you read when you don’t have to that determines what you will be when you can’t help it.”  ~Oscar Wilde

Incorporating quality tools outside of work

In celebration of World Quality Month, the feature story of November’s Quality Progress is “Off the Clock,” which highlights the passion of quality professionals and their tendencies to incorporate quality into their daily lives.  In fact, Jennifer Stepniowski, Pro QC’s Special Project Manager, is included in the article as she discusses using checklists, brainstorming and affinity diagrams to organize summer fun for her family.

For most of us in the industry, quality is a passion.  It’s something we incorporate into our routines seamlessly.  And, it’s something we at Pro QC believe will help raise awareness to those outside of the industry.  World Quality Months provides us with an ideal opportunity here.  We talk so much about the technical aspects of quality due to the nature of the work of we do, but quality can be found throughout our personal lives as well.

A few suggestions from our team for incorporating the quality tools we know and love outside of work includes:

  • Checklists – Checklists are a significant time-saver that come in handy for just about anything.  Outside of work, use them to create grocery shopping templates or to organize travel.
  • Brainstorming – Taking a few moments to really consider all of the options and incorporate others into that process saves time and generates new and fresh ideas.  Outside of work, use it for menu or vacation planning.
  • Fishbone Diagrams – Figuring out what the root cause is saves time and gets problems solved much faster than trying to patch up the “bones.” Outside of work, use it for anything that continues to be a problem such as time management issues. Getting to to the root cause will avoid continuously patching it up.
  • Flowcharts – Flowcharts are excellent visual devices that both educate and serve as tools for identifying continuous improvement.  Outside of work, flowcharts are a great way to teach children how certain tasks and responsibilities should be performed.  It can also improve the efficiency of household chores or other common tasks.
  • Line Graphs  & Histograms (Bar Charts) – Histograms are great for visually representing data collected and line graphs show a pattern of data in time order.  Outside of work, they’re great for organizing chores or even fitness and/or dietary information.  These are also excellent tools for analyzing budget information.

What are some other ways we can incorporate quality into our daily lives?

“Quality begins on the inside… then works its way out.”
― Bob Moawad

Are trade shows still relevant?

In today’s fast-paced digital world, we have asked ourselves if exhibiting in trade shows is still a relevant form of reaching people.  Overwhelmingly, the team agrees that while they are not an inexpensive way to market, it remains one of the most favorable.

Face-to-Face Connections – Emails and Skype calls only go so far to connect people.  At trade shows, we’re able to talk with people one-on-one and answer any specific questions and/or concerns they may have about sourcing and the role of 3rd party quality providers in that process.  We also learn from those visiting our booths, through their shared experiences and perceptions of the industry.

Reconnecting – We have several existing clients that frequent the same shows we exhibit at.  As an opportunity to catch up, it is always a welcome surprise to see a familiar face stop by our booth.

Scanning the Environment – Attending or exhibiting industry shows gives us a unique opportunity to assess the environment.  It allows us to examine trends within our markets and provides significant insight for future strategy development.

As the Global Sources Electronics & Components show comes to an end in Hong Kong, we are pleased with the steady traffic and representatives from so many regions of the world that came together for the event and spoke with us regarding reducing quality risks and cost.  Compared to previous shows, we did see less of a presence from European countries but noted a significant number of attendees from California, Brazil, and Russia.

Candace and Shirley traveled over from Pro QC’s Shenzhen office, and Bruno and Shirley traveled from our headquarters in Taipei, Taiwan.