The Trade Union Act 2016 will come into force on 1 March 2017. The new rules apply to any industrial action for which the ballot opens (by sending out voting papers) on or after that date.

The main changes the Act makes to the pre-conditions for lawful industrial action to be taken are:

• 50% turnout – at least half of those balloted need to cast a vote before it is valid. If the ballot is valid, then, as before, a simple majority must vote in favour in order for the ballot to mandate industrial action, subject to special rules for key sectors (mentioned below).

• 40% support in key sectors – in addition to the 50% turnout rule, where a majority of workers involved in the dispute are in key service sectors (health, education, fire, transport, energy, and border security), 40% of all eligible voters must vote in favour of industrial action. For health and education, private sector workers are included only if they are in publicly funded hospitals or schools; in the other sectors, all private sector union members are included in the threshold if they are delivering the specified services.

• Six month limit – there is a six month limit (up to nine months with employer agreement) on a mandate for industrial action, after which another ballot is required.

• Two weeks' notice of industrial action must be given to employers – seven days if agreed. The new limit applies where the employer receives a notice on or after 1 March.

• Ballot papers – they must set out the detailed nature of the issues in dispute; the types of action "short of a strike" and an indication of time periods for action.

• Union supervision of picketing – some recommendations in the Code of Practice on Picketing, notably the appointment of a picketing supervisor, will now be legal requirements.

The ban (in the recruitment sector regulations) on using agency staff to cover striking workers remains in place. The government consulted on lifting this ban in 2015 but as yet there has been no indication of whether the ban will be abolished.

More likely perhaps is a change to voting in industrial action ballots – last year the government announced an independent review of electronic voting (a commitment in the Act), although the final report is not due until the end of this year. At the moment, only postal voting is allowed and trade unions had argued that one of the reasons for apparently low turn-outs in strike ballots was the lack of e-voting.