When a repair creates a new product: the line where fixing becomes making

In general terms, a repair that restores a product to its original design, using suitable parts, remains a repair. A change that substantially modifies the product, such as altering its function, its performance, its intended use, or its safety design, can move it into the territory of a new product, with duties closer to those of a maker.

The question to ask is whether the result is still the product that was originally placed on the market, in design and safety terms, or whether it has become a different product wearing the old product's name. A repaired kettle with a new element of the same specification is still the same kettle. A kettle rebuilt with a different heating system, a different capacity, and a different control is arguably a different product, whatever its shell suggests.

Changes that tend to cross the line include altering the power, capacity, or speed of a product, changing its intended user group, such as converting an adult product for child use, replacing a safety system with a different design, combining parts from different products into a hybrid, and changing the product's structure in a way that affects its strength or stability. Each of those changes creates a product whose risks were never assessed as a whole, because the original assessment covered a different product.

Changes that tend not to cross the line include like for like part replacement, routine servicing, cosmetic renewal, and repair of a single fault to the original specification. The distinction is not the amount of work, but the nature of the change: restoring a design versus creating a new one. Illustration: a workshop that converts a mains powered tool to battery power has created a new product in substance, while a workshop that replaces the same tool's worn switch has repaired it.

Crossing the line matters because duties follow the maker role. A person who creates a new product in substance may need to assess its risks as a whole, ensure its labelling and instructions match the new design, arrange its identification and traceability, and meet the responsible person and market duties that apply to a maker. Those duties are heavier than repair duties, because they concern a product whose safety has never been established as a whole.

Ignoring the line does not remove the duties; it merely leaves them unmet, which becomes apparent if the rebuilt product fails or an authority asks for its file. A repairer who recognises the line early can either scale back the change to a genuine repair, or embrace the maker role properly, with a full assessment and file. Either course is safer than drifting across the line unknowingly.

Assessment before work should compare the intended result with the original product across function, performance, user group, safety systems, and structure, and should record the comparison and the conclusion. Where the comparison shows a substantial change, the work should pause for a maker level assessment, including a fresh risk assessment for the new design, before proceeding. Where it shows restoration, the repair can proceed on repair records alone.

That pre work assessment should be written, even briefly, because it is the evidence that the line was considered. A repairer who can show a written assessment, with reasons, will be treated differently from one who never considered the question, even where the conclusion is later debated. The assessment is also a useful discipline for the workshop, preventing ambitious rebuilds from starting before their implications are understood.

If the line is crossed, the rebuilt product should be treated as a new product for safety purposes: a full risk assessment, appropriate testing, correct labelling and instructions for the new design, proper identification, and the maker duties that apply in the market of sale. The product should not be sold under the original product's documentation, because that documentation describes a different product, and selling under it misleads buyers and authorities alike.

The rebuilt product's description should also be honest about its nature. A buyer should know the product is a rebuild with a new design, not merely a repaired original, because that knowledge affects their judgement about its safety, its parts, and its support. Honest description of a new product is not a marketing disadvantage; it is the foundation of the trust a new product needs.

A workshop stays on the repair side by setting its own limits: repairs restore to original specification, substitutions are documented and equivalent, safety systems are restored rather than redesigned, and changes to function, user group, or structure are refused or referred for a maker level assessment. Those limits, written as workshop policy and briefed to staff, prevent gradual drift, where each small change seems harmless but their sum creates a new product.

The workshop should also review its completed rebuilds periodically, asking whether any crossed the line unnoticed. That review, using the comparison method described above, catches drift early and allows a product already sold to be addressed, rather than discovered by an authority. A workshop that reviews its own line is a workshop that takes its safety role seriously.