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We need NADCAP certification

A discussion started in 2004 and continuing through 2017 . . .


Q. Statistical Processing Control We recently went through a NADCAP audit for chemical processing and were informed that by the time of the next audit we have to implement SPC for at least on of our chemical processes. We perform the following processes: Chem Film, Passivation, Etching/Pickling, Primer and Paint.

I'm thinking that SPC should be implemented for Chem Film first (seems like the easiest process to start with). I'm not sure what tools (i.e. software) I need to do this. Does anyone have any experience with SPC on a Chem Film process or any suggestions as to what software to use and would it really be effective to do SPC on this process?

Happy Holidays

Thomas Kristensen
NDT, Chemical Processing - Arleta, California, USA


A. The easiest way I know of to make SPC meaningless is to start off measuring things because they're "easy". What you want to start with is something MEANINGFUL!

First, take a look at the quality data you (hopefully) have on your chemical processes. Determine which one is in fact causing the most problems. THAT is where you want to start. Now, in that process, what characteristic does the process impart to the product that most determines whether or not it is good. That is what you want to start measuring. The point of this exercise is to determine the variability of the process. In reality, that is all SPC does; it measures the variability of a process' outcome.

Once you've established the variability, you can start to use the data you've collected to reduce the variability through a variety of statistical tools you can get out of the literature.

Software? Why? You don't really need anything more than a good spreadsheet for basic SPC. Software doesn't really become worthwhile until you start using some more advanced things (like Taguchi methods). To start, you basically need to make sure the people involved understand the point of the exercise (and the point should NOT be to make an auditor happy). Making a process perform predictably and consistently good is the goal.

James Totter, CEF
- Tallahassee, Florida


Q. Is SPC required by NADCAP? If so, how can you pass without it or by only using it on one process? If not, how can it be required by next year?

Chris Jurey, Past-President IHAA
Luke Engineering & Mfg. Co. Inc.

Wadsworth, Ohio


A. If your SPC program is to be effective it must be done manually. The person doing it should be the operator of the process. For your process you'll need individuals and moving range charts.
1) Collect 25 or more data points for each parameter of interest. Determine average. For the data points in in the sequence they were taken determine the difference between adjacent points, ignore signs. Determine average of these differences.
2) With first average add second average times 2.66 to get upper control limit and subtract second average times 2.66 to get lower control limit.
3) Take second average and multiply by 3.65 to get the upper control limit for the range.
4) Draw these lines on a control chart and then follow these simple rules. If a point is outside any of the control limits determine the cause, perform and action the rectify the problem and devise a prevention so it does not reoccur, (CAP). Seven consecutive points above or below the average is also and out of control condition as is seven consecutive points rising or falling.

The mistake most people make is getting the operator to react to out of spec. points. Out of spec. points mean the process is not capable and not fixable by the operator. reacting to these will increase the variability of the process. Leave it to your engineering people to resolve this.

The control charts should be at the operators station posted in such a way that they are easily observable by by others. Peer pressure keeps everyone honest which is why it must be done manually. Out of site out of mind.

If done right this is an extremely effective method of process control.

Ronald Zeeman
Coil Coating - Brampton


A. The Appendix A statistical techniques requirements of AC7108 (Nadcap chemical processing) give an implementation period, with a milestone plan done by the initial audit and two years for the first process and additional processes covered at subsequent re-accreditation audits.

Also, it is important (and required) to analyze your nonconformance prior to choosing the first project. You have some freedom here in choosing criteria (part-per-million, scrap or rework costs, customer return data, etc.) The point is not "I think I'll do chem film first", but you do a project that will improve your losses (and therefore of interest to your customers).

Your customers and PRI are not interested if you know how to apply SPC to meet Appendix A, but that you use it as a continuous improvement tool. This is done using the (simple) Pareto analysis and the (perhaps more time consuming) Failure Mode Effect Analysis.

Douglas A. Hahn
- Rocky Mount, North Carolina

October 28, 2010

A. As Doug has mentioned, the purpose of Appendix A is to promote continuous improvement. However, in a small shop environment, what it really promotes is companies fabricating data simply to meet the requirement. It's not as simple as finding something that you can improve. It's finding something you can collect #'s on and be able to apply the tools. Eventually one does begin to run out of real problems and just brainstorms to come up with anything they can think of. Complying with this one requirement is the biggest headache with the whole Nadcap process. If it is truly worthy of keeping it should be required by all task groups. This one requirement requires a lot of manpower and time which leads to higher costs. Who does PRI and the Primes think is paying this bill? This requirement puts chem processors at an economic disadvantage over those monitored by different task groups.

Bob Hill
- Glendale, Arizona, USA


Q. Hi,I need the Nadcap certification and I don't know what I gotta do...

Can anybody help me?

Oscar Gutierrez
product designer - Gdl, Mexico


A. It's a very big job, Oscar, but start the process either at the NADCAP site at,or by retaining a consultant to set you up for it.

Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

March 24, 2011 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. We are looking at the NADCAP certification and was wondering the cost to be certified and the periodical audits. How much time does a company need to prepare for the certification? I would appreciate any information.

Joan JoAn
Quality ISO Manager - Columbia, South Carolina

March 29, 2011

A. Hi Joan

The process is not too scary. Ted is right; the place to start is PRI. They don't bite and can be very helpful.

How much work is required depends on how you are currently operating. If you are working exactly to the requirements of your customer specs and recording test results, the answer is very little. Don't forget that the AC7108 requirements are not imposed by PRI. They are collected there by your customers instead of adding them to the specs and have the same authority.

One of the requirements is to carry out your own audit to the 7108 requirements. You will be doing annual audits anyway (I hope) so do this one instead, put right your findings, and you will be in reasonable shape for your first inspection.

Don't be put off by a couple of minor non-conformances.
Major findings usually imply an impact on product quality and if there are any, you should be glad to fix them. Zero findings is an extremely rare event.

You can, of course , employ a consultant but I believe that it is much better to own your own process.

Go for it! Good luck!

geoff smith
Geoff Smith

April 17, 2011

A. Hi Oscar,

You must start with downloading the AC7108 checklist (and applicable slash sheets). You can find them on
Then you must make sure that you are compliant with ALL criteria. The only answers allowed are YES and N/A.

even if you are fully compliant to customer specifications/requirement, then still it is a lot of work. Do not underestimate this, you probably cannot do this on your own. Run through the checklist and find out how compliant you are. Depending on the scope of the audit, I would suggest preparing a year before submitting for the first accreditation. Costs are several thousands of dollars, also depending on scope. The audit will take 3-5 days and is very intensive/detailed.
Then ask for a Nadcap audit. I would advise you to do one of PRI's courses on Nadcap audit preparation. See PRI website for more information.

Good luck.

Best regards

Jeroen Visser
- Geldrop, Netherlands

July 28, 2011

A. I have been through the NADCAP Chemical Audit twice. Contact PRI. Print off the audit, take your procedures and go line by line through each question of the audit and find where in your procedure the question is answered. Then note next to the question the procedure number and the section of the procedure where the answer can be found.
Make sure that you have objective evidence of all parts of the operation, calibration records, solution analysis, records of tank additions, etc. Make sure your operators are following your procedure(s) exactly. The preliminary audit will probably be 5 days the first re-accreditation audit will probably be 3 days. Audit all your operations and operators and make sure what you say is what you do.

Remember any NO answer to a question is a finding.

Donna Warner
- New Century Kansas USA

Periodic testing to fulfill Nadcap requirements

February 7, 2011

Q. Was hoping someone with some Nadcap experience could lend some advice....

In preparation for our as of yet unscheduled chemical processing Nadcap audit, I am going through all of our internal procedures to hopefully verify that they will fly in the eyes of Nadcap, and if not, make the necessary adjustments. One of the items I've come across pertains to the periodic (monthly) testing that we send to a 3rd party for hardness and purity on gold plated coupons. In the past we have always sent out two coupons, 1 hard gold, and 1 soft gold for purity and hardness analysis. However, after rereading the "major" gold plating specs (such as ASTM B488, Mil-G-45204, AMS 2422)it seems that they would require periodic testing to be done for each item that you plate, not just generic coupons. The problem is that being a job shop, we plate hundreds, if not thousands of different part numbers on a monthly basis. As you could imagine, this would be extremely cost prohibitive to send out representative samples for each part number on a monthly basis and very labor intensive if we were to bring the testing in house.

My question is, is there a way around this? Is maintaining traceability from coupon manufacturing to testing results enough?

Thank you for your insights!

Mike Brady
Plating Shop Employee - Chicago, Illinois, USA

February 8, 2011

A. Got to love Nadcap and all that it makes us go through like reading specs cover to cover and actually complying with all the requirements rather than choosing which ones we mostly meet! All kidding aside, we've chosen to SKIP altogether becoming accredited for gold - too many combinations and permutations. My take on it, and we've been audited to the MIL-G-45204 spec by many, many primes, is that your approach using coupons is acceptable. The one thing you may run into is that if the lab you're sending out purity and hardness isn't Nadcap accredited, they won't accept the results. We were sending our gold and silver coupons back to the supplier's lab and it didn't fly with Nadcap. Good luck; your first audit is always torture only to be outdone by the torture you'll experience when 1/2 of your initial responses get bounced back.

milt stevenson jr.
Milt Stevenson, Jr.
Syracuse, New York

February 9, 2011

thumbs up signThank you for your words of encouragement :)

Seriously though, thank you for your input. The lab we use is Nadcap accredited so we should be good there.

To make this more challenging, we do not supply any primes directly, so our company is not incredibly familiar with their specific requirements. I would think if a similar practice to ours is accepted by the primes than no doubt Nadcap will accept it without hesitation :sarcasm:.

Thanks again for the input.

Mike Brady
- Chicago, Illinois, USA

Planning on going NADCAP

September 11, 2013

Q. I work for a company that has been up and running for over 150 years. 35 years I have worked there so far; I love what i do. We are considering going Nadcap approved. I would like any feedback on the standards that are needed to pass, such as certifications on any things related to our field; also what paperwork such as plating procedures we do. Most of our work is MIL spec work and some ASTM work. Thanks, Rick

Richard Tetens
Master Plater - Huntington Station, New York

September 18, 2013

A. Hi Richard,

You need to get yourself registered with Nadcap so that you can access their documentation.

Once registered you will have access to the AC checklists (for plating/anodising/conversion coating it will be AC7108, for paint AC7108/1) you will need to carry out a gap analysis (basically audit yourself to the AC checklist), then keep auditing yourself until you are happy all the gaps are closed.

Personally I would hire a Nadcap consultant, they can take a lot of pain and time out of the preparation for a Nadcap audit. A lot of these guys are ex-Nadcap auditors so have a good idea about what the Nadcap auditors will be looking for.

Brian Terry
aerospace - Yeovil, Somerset, United Kingdom

March 9, 2017

Q. Hi All,

I read through most of thread 27698, "Trouble with NADCAP Audits" and saw a lot of helpful information, and I am trying to find some more current information if available. Does anyone know what the cost for a business (with no AS9100 or AC7004 accreditation currently) to become Nadcap certified, would be? I know it's a little flexible depending on the length of the audit, and that either AS9100 or AC7004 are pre-req's for Nadcap.

Thanks for any help!

Lizzy Check
- Akron, Ohio and United States

March 9, 2017

A. Hi Lizzy
Ask PRI.
You will find them very helpful.

geoff smith
Geoff Smith

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