Global Sources
Ready to import from China? Find verified suppliers on Global Sources.
Share / Recommend:

Common questions about what an AQL inspection guarantees

by Renaud Anjoran

Recently I got 4 messages from buyers who asked me to clarify what an AQL inspection guarantees and what it does not guarantee.

The problem is, explaining the concept of the AQL (Acceptance Quality Limit) is not simple.

Here are two examples of questions (rewritten for clarity and brevity).

Q: We paid a QC firm, they found a number of defects below the AQL limit of 1.5%. Then we found that the proportion of defects was higher than 1.5%. The QC firm said they are only responsible for the cartons they inspected. Is it normal?

A: No the QC firm should not say their findings are only applicable to the cartons they inspected. That is unprofessional. They should say it is perfectly possible that, sometimes, the proportion of defects in the whole batch will be higher than that among the samples they checked.

But of course, no QC firm will accept liability above 10 or 15 times what they were paid for their service, for a random inspection.

Q: We buy from a Chinese supplier, and we conduct AQL inspections with a limit at 2.5%. But our customers, in our country, complain as soon as they find a few defects. What is a simple definition of the AQL that I can give to them? 

A: The definition of AQL as the “quality level that is the worst tolerable” comes from the ISO 2859-1 standard.

Here is my simple definition: ”I want no more than 1.5% defective items in the whole order quantity, on average over several production runs of that one product and with that one manufacturer” means the AQL is 1.5%.

But, from experience, the AQL is a concept too time-consuming to explain to your customers. Heck, 99% of importers do not even understand that concept correctly!

You are better off doing two things:

  • Looking for good manufacturers, and setting the AQL as low as realistically possible. Let us say 1.0%.
  • Taking a margin of safety: looking at the “consumer’s risk quality” table, and based on your usual sample size (let us say 200 pcs), you can only promise to your customers that there will be less than 4.6% of defects in 90% of cases.

Is that scary? 4.6% of defects, or more, about 10% of the time?

Yes it should be scary. But that is how the AQL works.

If you really want to understand the concept of the AQL, you should spend about 20 minutes watching these 3 videos. I promise it will help!

How to Read the AQL Tables
When Applying the AQL tables Does or Doesn’t Make Sense
Why the AQL tables are not in favor of the buyer

Renaud Anjoran has been managing his quality assurance agency (Sofeast Ltd) since 2006. In addition, a passion for improving the way people work has pushed him to launch a consultancy to improve factories and a web application to manage the purchasing process. He writes advice for importers on


0#Old School New Body2014-05-16 22:54
Your post demonstrates you happen to be quite well written and capable
of writing pleasing content articles. Might you provide articles for other individuals?

I can compensate you for your work (per hour, per page, .etc).
Reply | Reply with quote | Quote
0#Metabolic-Cooking-2014-05-16 11:45
Thanks very interesting blog!
Reply | Reply with quote | Quote
0#Natural Clear Vision2014-05-13 20:42
I'm a wordpress plugin programmer. I actually
have developed a plugin that should obtain web browsers emails to your database without having their contact.
I will be trying to get beta evaluators and also since you'll be gaining sizeable portions of internet site visitors, I'm checking out your web blog.

Feeling attracted?
Reply | Reply with quote | Quote
0#tumblr.com2014-04-25 09:45
I know this if off topic but I'm looking into starting my own
weblog and was wondering what all is needed to get set up?
I'm assuming having a blog like yours would cost a pretty
penny? I'm not very web savvy so I'm not 100% sure. Any tips or advice would be greatly appreciated.

Reply | Reply with quote | Quote
0#Eat Stop Eat Review2014-04-23 21:24
Our company is giving out Nearly a dozen bitcoins to our very lucky winner of a blog website
manager with the decided on prize code. The final results shall be out in
1 month time. The prize code is: ABCXQ8
Reply | Reply with quote | Quote
0#Darell2014-04-17 16:38
I'm a plugin creator for wp. We've launched a plugin which
could produce web surfer's emails on your database without having their connection.
I was trying to find beta evaluators and since
you might be getting substantial ranges of internet site visitors, I am pondering you and your blog website.
Are you attracted?
Reply | Reply with quote | Quote
0#archive.org2014-04-07 04:19
Hi colleagues, fastidious article and good arguments commented here,
I am in fact enjoying by these.
Reply | Reply with quote | Quote
0#Is Get Him Back2014-04-06 18:35
I am a engineer and I've just created a ground breaking social network website.
I'm also looking for beta test candidates to search and give it a shot.

Would you like to subscribe? We will compensate you.
Reply | Reply with quote | Quote
0#Http://Dog-Food-2014-04-04 13:19
It's very simple to find out any topic on net as compared to
textbooks, as I found this article at this website.
Reply | Reply with quote | Quote
0#Download Critical2014-04-02 04:11
I am regular visitor, how are you everybody?
This paragraph posted at this web page is genuinely pleasant.
Reply | Reply with quote | Quote
0#Reviews on2014-03-26 03:45
Great post however I was wanting to know if you could write a litte more on
this topic? I'd be very thankful if you could elaborate a
little bit further. Kudos!
Reply | Reply with quote | Quote
0#Critical Bench2014-03-22 22:30
This is really interesting, You are a very skilled blogger.

I've joined your feed and look forward to seeking more of your fantastic post.
Also, I've shared your site in my social networks!
Reply | Reply with quote | Quote
0#Stefan2014-03-22 15:44
Thanks for the auspicious writeup. It actually used to be a leisure
account it. Glance complicated to more introduced agreeable from you!
By the way, how could we be in contact?
Reply | Reply with quote | Quote
0#Eczema Free Forever2014-03-19 19:20
When I originally commented I appear to have clicked
the -Notify me when new comments are added- checkbox and from now
on every time a comment is added I get four emails with the exact same comment.
There has to be an easy method you can remove me from that service?
Reply | Reply with quote | Quote
0#Reinaldo2014-03-19 06:14
Your post demonstrates that you're pretty well written and great for writing attention-catching writing.
Do you write for other individuals? I can also compensate you for your work (hourly, per piece, .etc).
Reply | Reply with quote | Quote
0#mygirlgetsringreview2014-03-19 04:41
May I inquire if you could be alright with paid blog posts?
All I'd need is for you to put together website content for myself and just a hyperlink or mention of my online site.

I will compensate you.
Reply | Reply with quote | Quote

Add comment

Security code

Stay Connected

Get Import from China Headlines by E-mail

Attend the Global Sources Summit

  • For online & Amazon sellers
  • Interactive training led by sourcing & Amazon experts
  • Learn how to source profitably, avoid pitfalls
  • April 17 - 19, 2017 in Hong Kong
  • Co-located with Mobile Electronics and
    Gifts & Home shows

Learn More

Join the Smart China Sourcing Facebook Group
  • Connect with other buyers
  • Ask questions
  • Get advice from experts

Join Group

Join Global Sources on Facebook

Be our fan now for the latest sourcing news, practical sourcing guides and expert advice.

Follow Global Sources on Twitter

We'll keep you updated with tweets on sourcing news, trade resources & more.

Connector Manufacturers From Global Sources

Global Sources - New Products from DVI Connector Manufacturers