New job contract clause - normal or not?

[iamsoshocked]

DS has just got his first job offer for September. It's for a Business/engineering consulting company. Looking through his contract, he called us to ask if it's normal to have a clause which says if you leave the company, you can't work in the same field for 18 months. Or words to that effect anyway.
What if he wants to move to another company? Does he have to be out of work for 18 months? That can't be right.
(we are both freelance so have no experience with this kind of contract).

The advice you have had from others usually is right for someone starting out, but I would caution everyone who says that they’re not enforceable. My husband currently has a high court injunction on him (with a 4 day trial to be had in June) regarding exactly this. He was senior at his old company (but not on the board of directors). We have had three different solicitors look through his contracts and they all agree that his shouldn’t be enforceable but his old company are vindictive and want to “make an example” of him (their words).

I think your son will be fine due to it being his first role, just wanted to say that it’s not always so cut and dry.

My company is 6 months for a direct client although this can be reduced by negotiation

18 months in the same field can surekt not be forced in any way at all

So, what happens when you want to move jobs? Do you have to sit on your arse for a year? Surely that can't be right?
Am I allowed to show the contract clause on here? Or is that a bad idea/

It would not be enforceable to deprive someone of an income. They can choose to pay your son to sit at home over that period though. That they can enforce