Who needs an induction
Under CDM 2015, contractors must make sure every worker under their control has a suitable, site-specific induction - unless the principal contractor has already given one. Visitors usually get a shorter version covering the rules and hazards they'll meet.
What to cover
Site rules and access, the main hazards and how they're controlled, emergency arrangements and assembly points, first aid, welfare facilities, PPE requirements, how to report accidents and near misses, and who's in charge. Keep it specific to the site - a generic talk doesn't count.
What to record
Name, company, role (worker, visitor or subcontractor), site, date, who gave the induction, and when it expires or needs refreshing. Note any cards or competences checked at the same time.
Refreshers
Re-induct when the site changes significantly - a new phase, new hazards, changed access - and at the interval your own procedures set. A register with expiry dates makes the refreshers easy to spot.