[toast0]

Tradespeople are typically independent contractors. You hire them to do a task, and they use their own judgement on which tools to use. You don't order them to use a tall ladder...

[marcosdumay]

The regulations that tradespeople must obey and how they are contracted varies from one country to another.

[Crunchified]

And hopefully these independent contractors are insured. It may well be insurance requirements that limit the use of ladders.