Fire and Emergency is reassuring strike action by unionised firefighters will not reduce or impact the services

NZ Professional Firefighters Union members are taking industrial action - starting on the 11th of August - after failed bargaining over pay and working conditions.

Staffing shortages, high workloads, aged trucks and a lack of occupational and mental health initiatives - are among the issues raised.

Fire and Emergency Deputy National Commander Megan Stiffler says they're disappointed the union's rejected their offer of a 5.1 percent pay rise over the next three years, as well as increases to some allowances.