Sometimes, though it is not clear whether a person is an employee or a self-employed contractor. Under the Employment Relations Act, unions have a legal right to enter workplaces. This can be either for purposes related to the employment conditions of its existing members or for legitimate union business. This includes recruiting new union members and discussing union business with existing members. The law also requires employers to accept union representatives entering workplaces.
Union representatives have to act in good faith when doing so.
For example, union representatives must have regard to normal business operations and they have to give a reason for wanting to enter the workplace. You can choose whether or not to talk to them or you can choose not to. You can choose whether you wish to join a union or not. You can even choose to group together with other employees and form your own union if you wish to. The relevant union can advise employees what they need to do to join.