Defective Rate PPM (Parts Per Million) 


Xmultiple's Engineering Department

PPM (Parts per million) is a measurement used by many customers to measure quality performance.

Definition: One PPM means one (defect or event) in a million or 1/1,000,000

In the past a good supplier would have a defect rate of less than 1%, (10,000 PPM). However, production and quality control procedures have improved and expectation was increased to 0.1% or 1,000 PPM. Now the rate for most connectors and components is targeted at 25 PPM or 0.0025%

To calculate: For example, if you had 25 pieces defective in a shipment of 1,000 pieces. 25/1000= .025 or 2.5% defective. .025 X 1,000,000 = 25,000 PPM.

Use the PPM Calculator:

How to calculate PPM is best explained in an example. Let's say, a manufacturer produces 10,000,000 parts per year for their customer. The manufacturers plant operates around 5 days a week, 50 weeks per year or 250 days a year in most cases. Let's assume most customers requirements are 25 PPM. That means that the manufacturer would be allowed 25 pieces for every 1,000,000 pieces or 250 defective parts per year. Or to put it another way, one bad part per day! In this example we did not say one bad part per day per person or job, or shift or machine. One bad part for the entire plant for 24 hours! This is what Xmultiple has achieved and we meet our customers expections for the lowest possible defective rates.

This rate is possible and even though many manufacturers still are using the same manufacturing methods which were responsible for the 5 or 10% scrap which use to be accept.

The monitoring and measurement systems we have today have paved the way for improved quality. We can now control the process in order to control the quality. Quality can not be inspected in after the fact. It is the result of careful planning, design, and execution.

To control our defective rate, Xmultiple uses a systematic and scientific approach to design and manufacturing in our facility. In addition, we use a high level of training of our personnel in the use of the tools and methodology so we can achieve these low PPM rates.


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