Quality Assurance (QA) and Quality Control (QC) are the processes most vital for a project’s success. However, professionals often confuse and intermingle the two.
Allow me to clarify the concepts. After reading this Quality Assurance Vs Quality Control (QA vs QC) blog post, I hope you will have a better understanding of the quality assurance and quality management processes.
Every project has QC and QA functions. The QC section communicates and coordinates with the QA department and the organization.
Since these processes work closely together, many professionals, especially those working in small and medium-sized organizations, do not understand the differences.
I met with many professionals involved in quality management during my ISO 9001 training course a few years back. These people had different backgrounds and were working across various fields.
One man told me he was working as a QA/QC engineer in his company, and I questioned him about his responsibilities and duties.
He replied that he goes around checking that the work is going as planned. He inspects deliverables with specifications and recommends corrective action if the deliverable has deviation or the process is out of control.
I then asked him about the quality assurance part of his job. He gave me the same response.
This told me he was not aware of his quality assurance responsibilities.
Often QA or QC or QA/QC engineers are not aware of their job responsibilities, especially in small organizations, because the differences can be so murky.
Sometimes, they don’t know the meaning of QA or QC.
This issue is prevalent in small or medium-sized organizations, where there are rarely the resources to hire both QA and QC engineers.
In such cases, the employee may possess the title of QA while working in QC and sometimes QC working as QA. Or their responsibilities and duties may be even more scrambled.
This ambiguity needs to be corrected because it does affect the quality of the deliverable and the success of the project.
Quality Assurance Vs Quality Control (QA vs QC)
Quality assurance is the process of managing the quality of the product.
Quality control is used to verify the correctness and quality of the product.
Before we discuss the differences between these concepts in detail, we have first to understand the term “quality.”
The most important and accepted definition is from Mr. Philip B. Crosby, who says simply that quality is “Conformance to requirements.”
According to ISO 8402:1996 – Quality Management and Quality Assurance Vocabulary standard, “Quality is the totality of features and characteristics of a product or service that bears on its ability to satisfy stated or implied needs.”
According to ISO 9000:2000 – Set of International Quality Standards and Guidelines for Quality Management Systems, “Quality is the degree to which a set of inherent (existing) characteristics fulfills requirements.”
Simply put, “quality” is about meeting the customer’s requirements to see if the deliverable is fit for use.
If a product meets or exceeds the customer’s requirements, it is said to be of high quality. It is of low quality if it does not.
Please note that, regardless of the product’s grade, the quality should be high; you cannot compromise with quality for any reason.
Quality Assurance (QA)
Assurance is an act of providing confidence that the customer can believe in.
QA guarantees the quality of the product, by ensuring that the output of the process is defect-free and conforms to all requirements.
Quality assurance is a process-based approach with the objective of preventing defects in deliverables while in the planning stage to avoid expensive reworks.
QA is a proactive process; it emphasizes planning, documenting, and finalizing guidelines. This helps communicate the product’s requirements and starts at the beginning of the project.
Once requirements are identified, you develop quality management plans to meet your stakeholders’ requirements and expectations.
Tools Used in the Quality Assurance Process
The following tools are used in quality management:
- Quality audits
- Process analysis
- Quality management tools.
In a quality audit, a team of external experts reviews the process and procedures. If there are any discrepancies, they will suggest corrective action, and they may offer advice on improving the process.
A quality audit is a great tool to ensure that the project follows best practices and approved procedures.
In the process analysis, you analyze for any improvements, discover the root cause of any problems, and identify any non-value-added activities.
Quality management and control tools include various diagrammatic techniques, which help you find ideas, make decisions, and prioritize issues. A few examples include an affinity diagram, a tree diagram, a network diagram, etc.
Quality Control (QC)
Quality control (QC) is a product-based approach that includes the activities and techniques for fulfilling quality requirements.
Quality control functions start at the beginning of the project. This is a reactive approach that helps find defects in deliverables. The objective of the QC process is to ensure the deliverables are defect-free and fulfill quality requirements.
The quality control process has the following objectives: finding any defects in the product, correcting them, and validating the deliverable.
QA and QC depend on each other; the quality control process receives input from the quality assurance process and provides feedback to the quality assurance process so that the quality assurance personnel can validate the process.
For instance, say the project team finds a defect during execution. They will correct it, and they will send the feedback to the quality assurance team.
This team will investigate the cause of the error and take action to ensure that it does not occur again.
After the process update, the quality control people will follow the updated process to stop the defect occurrence.
The quality assurance process takes inputs from the quality control process and vice versa.
Tools Used in the Quality Control Process
The quality control process has three main techniques:
- Inspection
- Statistical sampling
- The seven basic tools of quality
During an inspection, the deliverable is physically examined for any defects and to check it against the quality requirements.
A statistical sampling selects a random number of items from a batch to inspect them for any defects and conformance.
The seven basic tools of quality are: scatter diagrams, control charts, histograms, checklists, Pareto diagrams, cause-and-effect analyses, and flowcharts. These tools help find defects and the causes of defects.
The Differences Between Quality Assurance and Quality Control
Quality Assurance | Quality Control |
Defect prevention | Defect identification |
Avoid defects in the deliverable | Corrects defects in the deliverable |
A proactive process | A reactive process |
Process-based approach | Product-based approach |
Quality managing processes | Quality verification |
A quality audit is an example tool | A quality inspection is an example tool |
Although the QA and QC processes are different, they complement each other, and the output of one process is an input of the other.
The Benefits of Quality Assurance and Quality Control Processes
- High-quality output and eliminate waste.
- Increased efficiency of operations.
- Greater customer satisfaction helps your brand and grows your business.
- Lessen rework and after-sale support are required, which saves a lot of money.
- Encourages a high level of confidence and motivates the team.
Quality assurance and quality control are closely related; they both aim to deliver a defect-free product. Both processes are an integral part of a quality management plan, and failure to apply either of them will result in a low-quality product.
Summary
The quality assurance and quality control processes ensure that a product is defect-free and conforms to requirements. Both have the same purpose but use different approaches. Quality assurance is process-based, and quality control is product-based. Quality assurance designs a process to create a defect-free product In contrast, quality control prevents a defective product from reaching the market.
These processes play essential roles in the success of your project. They can only be achieved effectively if the team and the organization understand their significance.
Another process, “validate scope,” might be combined with quality assurance and quality control. I have written a blog post to explain this as well.
Please visit: Quality Control and Validate Scope.
Here is where this post on QA vs QC ends.
Are you involved in quality assurance or quality control activities? Please share your experiences in the comment section.
Very usefull, with relevent to construction sector , which is not orgnised as manufacturing we are sometimes facing non availability of competent QA /QC professional .
Please give in details related to construction.
This is a very interesting and insightful write up. What I would have liked to see further is how a quality management person can apply QA and QC in an organization with diversified products and services. For example printing division and insurance division?
Does one need to first understand the processestate express undertaking a quality audit of quality control exercise?
Hello Kaimfa,
Both processes are interconnected. It would be better for someone if they understood both processes.
Thanks so much. I really appreciate what I have learnt on this blog and above the simplicity and relatableness of the instances. Once, thanks a lot
You are welcome Emmanuel.
I have read your blog .Nice post ..Thanks for sharing your information…
You are welcome hitekschool .
Hi Fahad,
You are doing a great job, thanks a lot for this blog! Really helps to understand many concepts in different words (even more clear than in RITA book while, of course, the one should read RITA before the exam).
A simple acknowledgment of the fact that quality assurance is a process-based approach while quality control is a product based approach (and therefore we apply the same for audits and inspections) allowed to me answer easily to at least 4 or 5 questions during the PMP exam yesterday.
Thanks,
Dima
Congratulations Dima on passing the exam. I am glad that I could be of some help to you.
Hello Fahad,
Can we say that QA is the Manage Quality in Project Quality Management and QC is the control quality in Project Quality Management?
Thank you,
Mehul Parekh
Yes.
I have a research assignment which I have to do. From what I have just read, could one formulate a research title which reads:
Title:Study on the effectiveness of QA vs QC in a Manufacturing Environment.
Under financial constraints, which of the two would be a better option to invest in. Where one’s aim/objective would be to prove that QA provides a better means of ensuring quality? Or coming to a holistic conclusion that both QA and QC is equally important. I am still quite unsure, this is only the beginning of my research task.
Both are equally important and complement each other. In QA you define procedure and in QC you ensure that it is followed.
Quality is the satisfaction of the users by fulfilling and/or fully functioning its purpose under specific standards.
:)
quality is a word with several meaning and connotation. quality can mean excellence as in,this is a quality product.
Well said Banjo.
Have been struggling to understand this concept of how in reality these 2 tasks are performed. Your blog helped me in clarifying the difference and their uniqueness. Very well drafted with common and simple language. Thank you!
I am glad Angad that I could be of some help to you.
Please help me understand, how can a downtime be internal failure?
Thanks.
Please refer to the following blog post:
http://blog.lnsresearch.com/blog/bid/187432/8-Internal-Failure-Costs-Every-Company-Should-Watch
well,Here are sharing such a good or informative content about Quality Assurance Training.Thanks for the publish great ideas in this blog!
You are welcome QA Guru.
Well, here are sharing such a great and helpful information regarding Quality Assurance (QA). Thanks for the publish great ideas in this blog!
Thanks Guru.
I am working on road CONSRUCTION supervision with ambiguities on both QA and QC. You really solved my confusions. Now both of them are clear for me.
God bless you so much.
I am glad Tadesse that I could be of some help to you.
As you said ,”In quality assurance, you plan to avoid the defect in the planning phase. In quality control, you try to find defects and correct them while making the product.”. Pmbook says quality assurance is execution process
In quality assurance, during the execution phase you check that if the project team is following your plans and procedure correctly.
The statement is corrected.
Sir you said that in quality assurance we plan for processes, how can we say that quality assurance is an execution process
Thx. This post is indeed informative and crystal clear. Exactly what I needed as I start my journey as a quality assurer
You are welcome Sumaya.
If Risk Audit is done in the Controlling group, why is Quality Audit done in Executing?
I am taking the exam next week, thanks for your blogs!
Quality audit it a quality assurance function not quality control, that is why it is performed in execution phase.
Fahad,
Could you please contras Risk Audit with Quality Audit? I understand “audit” to be more of an inspection, or a reactive task compared to a proactive task. Thus I would assume all audits to be in the control process group.
Thank you!
Fahad,
After working on your sample questions from your eBook, I realize Procurement Audit is in the Close Procurements group, so now there is an audit activity in three different groups. I understand now, but maybe a discussion on the different types of audits might be helpful.
Thanks again!
Good idea. Sure I will write all types of audit happening in different phases/process of a project.
Fahad,
I just wanted to write back, I passed the exam on my first try! Please continue your hard work here.
Congratulations Aren on passing the PMP exam and thanks for your comment.
Hi Fahad
Really like your clear and relevant article on quality assurance.
Quality assurance might be compared to the direct and manage process of quality control.
Thanks Christopher for your comment.
Hi Fahad,
Thanks for this well-written article, it’s straight-forward and easier to grasp the key differences than PMBOK. Your website is a great tool for me in preparing PMP exam.
You are welcome Annie.
Let me know if you need any further help from me.
i am looking for an affordable online courses on Quality management, six sigma or any other related courses. kindly provide links.
The below given page has some course on six sigma and quality management:
https://pmstudycircle.com/pdu/
Very useful knowledge. Thanks.
You are welcome Fida.
God blesses you,thanks for the very detailed clarification.
You are welcome Mohamed.
It has very useful information as i am willing to appear for this exam.
I am glad Arpan that you find my blog useful.
I am reading all your PMP Certification Exam Study Notes and they are very useful and clear. I am preparing to take the exam in about 2 months, I will read every note but if you have more tips, I would really appreciate them!
Thanks for help us!
Pura vida (I am from Costa Rica)
You are welcome William.
You can download my free eBook on A2z on PMP exam and go through it. This book will help you in preparing the exam.
Let me know if you have any specific question.
Wow! I just have to say how impressed I am with the way you explain the differences clearly and easily.
I am so grateful for stumbling upon your blog before my exam in 3 days! Thank you!
You are welcome YJL. Hope you would have been passed the exam.
clear explanation
Thanks Sakthimurugan.
thnxx for inform sir.
which is the good field in working QA or QC
Both fields are good.
Thanks Fahad. Excellent explanations… not just this one but all the Blog posts… Thanks much.
You are welcome Amita.
Hello Fahad,
QA process using any tool of Quality management and control quality process.
My query is : whether Quality Assurance process is using 7 basic quality tools(any of 7) ?
These processes are interdependent on each other, so they may use any tool depending on the situation.
Assalaamu alaikkum Fahad,
I just joined in one of the IT company as QA Engineer. The company develops website required for one of the university. There is no QA department as of now. As QA Engineer what are the process that i should introduce here.
Thanks and Regards
Basheer
Wa-Assalam Basheer,
First of all you should check all procedures. There must be some procedures. Go and review those procedures, and check if they are following these procedures.
Today I can say I am QA/QC inspector but after reading your blog not before.
I love your comprehensive words which very simple & understood for all.
I love ? with fahad usmani blog.
I am glad that you liked my blog Iftikhar.
Very good informations and very simple to understand
Thank you very much Fahad
Thanks Imad.
very good job Fahad.
I am glad I found your website
You are welcome Sarika.
Going for exam in next 2 days…. I must say your articles and blogs are really helping thanks for great work!
Hello Daleep,
Good Luck for your exam.
Hope to see you here again once you pass the exam.
Hi Fahad,
Just wanted to say the super work you are doing by providing clear info in your blogs. I just came to know about this website yesterday, one day before my exam… I spent about 2 – 3 hours reading all your articles, which made concepts crystal clear and I passed PMP today. Keep up the excellent work :)
Regards,
Prasanna Kumar K R, PMP
Congratulations Prasanna and thanks for your comments…
Hi Fahad,
I’m a Recruitment Consultant in the oil & gas industry.
This blog is fantastic and very well explained!!
Thank you very much!
Regards,
Abhilash VJ
Thanks.
Hi Abhilash vj
Iam glad to see you comments on qa and qc. Its clear understand that qa works of to see that the product is defect free.While qc is working to make sure the product to produced is to free defect according to the custome requests.
Lastly have liked what you are doing oil and gas quality engineer.
Regards
Help me to answer this question …..?
Joe is a project manager on an industrial design project. He has found a pattern of defects occurring in all of his projects over the past few years and he thinks there might be a problem in the process his company is using that is causing it. He uses Ishikawa diagrams to come up with the root cause for this trend over projects so that he can make recommendations for process changes to avoid this problem in the future. What process is he doing?
A. Plan Quality
B. Perform Quality Assurance
C. Perform Quality Control
D. Qualitative Risk Analysis
I found that answer is B, but why ?….In PMBOK, under Quality Control (8.3.2.1) cause and effect daigram’s are explained …..so doesn’t it fall under Quality control …?
Thanks in advance.
See what the Joe is doing. He is only reviewing the processes used by his company so that the defects (occurred in past projects) could be removed. This is the job of quality assurance to develop a process in such way to avoid any defect.
In Quality Control Process, the project manager takes the sample or randomly checks the process in running project.
Therefore, the answer B is correct.
Thank you. This says that we need to read question carefully!!!. After your comment, I read the question again and I agree with answer. Thank you again.
You are welcome.
thanks for detail explanation..Much Appreciated
Fahad,
Thanks a lot for your reply. It clears my doubt.
What is your suggestion on taking on-line training? Now, I am doing the preparation on my own and don’t know whether i am in the correct direction. Any suggestions you can give would be appreciated.
Thanks.
It is your choice that whether you choose online course or live classroom training program. Both programs have their own merits and demerits.
Online programs are cheaper, convenient and flexible but lack the interactivity.
Classroom training programs are costly, held on fixed schedule and usually at big cities.
Regarding your preparation for the PMP exam, I have written a series of blog posts, you can visit them by clicking below given link.
https://pmstudycircle.com/2012/04/how-to-prepare-for-the-pmp-cert-exam-pass-it-and-become-a-pmp-part-1
Hope it helps.
Fahad,
I do find your articles good. For some reason, I am not able to understand this article. Can you please help me?
I understand that the QA ensures that the processes are set correctly to develop the product and the QC ensures that the final product is as per the requirements or not. Is my understanding correct?
I did not understand how QA takes inputs from QC and QC takes inputs from QA. Can you give me an example? Thanks for your help.
Hello Ravindra,
Your understanding is correct.
Quality Assurance develops the procedures, hence input for the Quality Control process.
During Quality Control, if you see that certain procedure needs some improvement or causing any trouble, then you can provide feedback to Quality Assurance to improve the procedures, hence input to Quality Assurance.
Bang on Target !!!!!!!!!
Excellent Article. Very informative and crystal clear. Thanks Fahad
Hello Fahad
I passed the PMP in first attempt. Your blog has helped me a lot in preparing for the exam. Thank you very much. Yours is an outstanding blog and very informative for all PMP aspirant and to others who are interested in PM. Well written and informative. Still i’m following your blog for latest articles on PMP. All the best and expecting more from you.
Regards
Saleem Angillath
Congratulations Saleem for passing the PMP Exam!
I hope this certification will help you to grow your career. Thanks for sharing your happiness here at PMSC.
Stay in touch.
Fahad
best page on the net, regarding QA vs QC , thanks.
Thanks for your comment.
Thanks Fahad,
I can imagine that I can apply QA without QC, but I cannot imagine to apply QC without QA. What can I check or inspect if it’s not defined well ( which is a QA step) ?
Hello Sameh. both processes complement each other.
I did not understand your question well. Please elaborate.
Really good
You are welcome.
Understood. Very well written. Crystal clear now.
Thanks a lot.
Thank you for posting your blog and sharing your insights and well organized thoughts and explanations. I wish I had come across your blog earlier in my travels, for today I failed my first attempt at passing the PMP exam. I was ill prepared, was too dependent on self-study via an internet website and life happens too often when one is trying to dig a hole and study in it…life always finds you to drag you away from all the fun of studying. Anyhoo, love your writing style which is not too pedantic and is not a repeat of what is found in the PMBOK which is a dread of a read for me. I never took the time to really discern between the two and it came to haunt me today.
Hello Jacqui,
I am very sorry to hear that you failed the PMP test in your first attempt. However, you still have you more attempts left with you.
Now, it is time for you take firm determination to pass the PMP exam. Schedule the exam and start preparing for it and let me know if you require any kind of assistance from me.
Good luck.
Where can I obtain this certification and what are the requirements
You can read all FAQs here:
https://pmstudycircle.com/pmp-faqs/