Many importers think of a new product and want to manufacture it in a Chinese factory, often without paying an engineer for DFM. Unfortunately, the manufacturer will seldom think of all the mistakes to avoid.

I found a good typology of injury sources (a concept at the heart of product liability) in New Products Management, a college textbook I used a few years back. It can serve as a good checklist for purchasers:

1. Inherent risks (example: dynamite might explode) cannot be avoided. There isn’t much an importer can do about it, except reduce the likelihood that bad things happen.

2. Design defects can cause the manufacture of an unsafe product in three different ways:

• The design may create a dangerous situation (example: a heavy piece of furniture that is not stable and can top over easily).
• A safety device might be missing (example: a hair dryer without an overheat switch).
• Design may call for inadequate materials (example: construction materials that may deterioriate quickly in performance).

3. Defects in manufacture are caused by inadequate or unstable processes. It results in defective units (example: poorly welded ladders).

4. Missing instructions for use or (more importantly) warning against particular uses are a big problem, even if the product itself is fine. Example: a barbecue that can’t be used indoor — there might be several warnings, but a court might conclude that they were not obvious enough.

5. Dangers can also appear after use (example: spray cans that explode when burned in fireplaces).