The call came from Construction Skills Certification Scheme chief executive Graham Wren as he handed out the 2 millionth CSCS card.
Wren was speaking at an event in London to celebrate the scheme’s 20th anniversary.
Millions of workers are now cardholders as technology continues to make the scheme increasingly efficient.
But Wren said some contractors are still wasting money unnecessarily registering people who don’t need to prove their skills on site.
He said: “I have spoken to receptionists at large contractors who were as baffled as I was about being card holders.
“Also you don’t need to make the delivery driver who fills up the site vending machine a CSCS card holder.”