The Trade Union Act 2016 introduces a new minimum turnout threshold, requiring a ballot turnout of at least 50% of those eligible to vote in order for the industrial action to proceed, and an additional threshold in respect of important public services where at least 40% of those eligible to vote must vote 'yes' to the industrial action.
The relevant definitions of 'important public service' can be found by following the links below:
The position in Wales may be very different to the rest of the UK. On 28 June 2016, Carwyn Jones, First Minister of Wales, announced that legislation would be brought forward to repeal sections of the Act in devolved areas as part of the Legislative Programme of the Welsh Assembly. Carwyn Jones said "significant parts of UK legislation relate specifically to public services that are clearly devolved, and, despite a number of concessions made by the UK Government to secure the Act, key provisions remain fundamentally harmful to Wales. Our legislation will seek to disapply these parts for our devolved public services".
In light of this, it appears that the National Assembly for Wales will be pushing ahead with its own legislation, but it remains to be seen what this will say and whether, for instance, the 40% important public service threshold will be repealed in Wales. It is possible that the UK Government will seek to challenge the Welsh Government's power if it indeed does act to repeal sections of the Trade Union Bill. Any challenge is likely to be based on the extent to which the Welsh Government does or does not have devolved power to repeal sections of the Trade Union Bill.