Better specifications, fewer quality disputes

“Good quality” is not an inspection instruction

If a buyer and a factory interpret the same requirement differently, even a well-intentioned order can go wrong. Phrases such as premium finish, strong packaging, or standard tolerance leave too much room for interpretation. Define what will be checked and how acceptance will be decided before production starts. The most useful specification is one that purchasing, production, and inspection can all use without guessing.

Build one controlled product pack

Bring the drawing, material requirement, finish, assembly instructions, labelling, and packaging specification into one identifiable revision. Give each document a date and revision code. State units explicitly and identify the dimensions that affect fit or function. Where a requirement is still undecided, mark it as an open question with an owner and deadline. Do not let an unanswered technical question quietly become the factory’s assumption.

Make appearance requirements visible

An approved sample is valuable for colour, texture, and general appearance, but it should complement written criteria. Photograph acceptable and unacceptable conditions where practical. Define the surfaces that customers will see, the viewing conditions for cosmetic checks, and the defects that matter. Keep reference samples protected and identifiable so they do not become confused with later trials or rejected pieces.

Explain the intended use

A small burr can be irrelevant on one surface and unacceptable on a sealing face. A slight dimensional change can be harmless on a cover and prevent assembly on a mating feature. Tell the supplier which interfaces and functions are important. Ask its engineering team to identify manufacturing concerns before tooling or bulk production. This creates an opportunity to resolve difficult requirements while changes are still manageable.

Control every change

When a material, dimension, finish, or packaging detail changes, record what changed, who approved it, and which orders it affects. Send a consolidated updated pack rather than expecting the supplier to assemble a specification from scattered chat messages. Request confirmation that production and inspection have received the revision. Retain the old version for traceability, but make it clear that it is no longer the production instruction.

Turn the specification into a checklist

For each important requirement, record the acceptance criterion, check method, equipment or reference needed, and evidence to retain. This makes the inspection plan a direct extension of the order. ASQ distinguishes quality assurance, which builds confidence in the system, from quality control activities that fulfil quality requirements. Clear documentation supports both.

Reference: ASQ: Quality assurance and quality control