Acceptance decisions can occur at several levels of management. At the lowest, a worker or inspector sees a fault, and brings it to the attention of a supervisor. The fault could be in the material, the process, or the output. The supervisor or project manager must then decide if the product or project can proceed.
There are four types of acceptance decisions:
- Go/No go - A product in an intermediate or final stage is inspected to determine if it can go to the next stage of processing. Go/No go acceptance is useful if a particular stage has a high rate of failure, or the next stage is an expensive step.
- Conforms/Does not conform - Conforms/Does not conform acceptance means that an item meets either a single or a variety of specifications. It can fail even if it passes all but one criterion. This category of acceptance frequently uses specification ranges determined in part through statistical analysis.
- Yes/No - Yes/No acceptance checks to see if project work meets certain criteria or checkpoints. Yes/No acceptance uses checklists to document that procedures and quality specifications have been met. The items on a Yes/No checklist may include: proper assembly, documentation, marking or packing.
- Pass/Fail - Pass/Fail acceptance often occurs at the final stage in a process or project. Specifications are used as a basis for determining if the project or item meets a variety of minimal expectations.
A project or product may be found unacceptable if standards or goals have not been met. Standards refer to quality issues outlined in government, association, industry, or company policies or project specifications. Failure to achieve those quality standards are grounds for immediate action.
Goals refer to a product or project not quite meeting the expectation as originally envisioned. For example, a product or project may meet less exacting commercial standards but not military standards. A more limited goal may have to be accepted or the project may have to be redesigned.
In any product or project, the acceptability is dependent on whether the customer finds that the results meet their needs. Failure to meet the customer's needs means redesign and rework or face the loss of the contract.
Shortcomings in quality may be acceptable if the price is too high for what was envisioned originally. Product or project redefinition may be required if the high standard is impossible. Project abandonment may also be considered.
It takes time to resolve a problem in a project or product. A less-than-perfect product may be acceptable in order to capture market share, or meet other deadlines. High quality products may receive more time to ensure customer satisfaction and repeat business.
Unacceptable work can be made acceptable through rework. Rework is the necessary work to bring a product or project back within specifications or standards. Rework is known as a compliance activity. The cost and time taken to do rework can cost more than doing it right the first time.
Therefore, rework should be considered a short-term solution. It is cheaper to carry out prevention techniques such as training, inspection of inputs, and frequent inspections of the process.
Rework can consist of remilling a machined part, repainting, reassembly, or replacement of a part or subassembly. In each case, only the work required to give the item or project a passing grade is completed.
Quality control may not always catch everything. However, once a fault is discovered, quality decisions need to be made on how widespread the problem is and the seriousness of the problem. If the product is produced as runs or lots it is easier to determine how widespread the problem is through sampling. Rework time, replacement and overtime costs, and loss of reputation if consumers reject the product, are all considerations facing management when encountering a quality problem.
Acceptance decisions are the key to quality control. Inspections and quality control analysis give the necessary information to make a logical decision by management. Rework should only occur if it is possible and cost and time effective.
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