CE marking on a connected product is rarely lost at the lab — it is usually lost months earlier, when an architecture choice closed off a clean path to compliance. This is the short checklist we run with hardware teams before they commit to layout.
1. Pin the intended use
Intended use drives the directives that apply, which drive the standards, which drive the design. If the intended use is fuzzy, every step downstream is fuzzy too.
2. Map the directives explicitly
EMC, LVD, RED, RoHS and REACH each carry their own evidence. A one-page map showing which apply and which standards you intend to use is the cheapest deliverable on the whole project.
3. Choose the radio module like it is a compliance decision
Pre-certified modules collapse a large chunk of RED testing. Discrete radios buy flexibility but cost test scope. Pick the trade-off consciously, not by default.
4. Plan pre-compliance against the actual standards
Generic 'EMC sanity checks' rarely catch what the accredited lab will catch. Plan pre-compliance against the specific clauses in the specific standards you will be tested against.
5. Build the technical file as you go
The technical construction file is the proof. Treating it as a documentation sprint at the end is how teams miss launch dates.