The Nuclear Regulatory Commission has ordered US commercial nuclear reactors to begin implementation of several key post-Fukushima safety recommendations.

Plants will have until 31 December 2016 to complete modifications and requirements of the three orders issued by NRC staff.

The first order requires the plants to better protect safety equipment installed after the September 11 2001 terrorist attacks and to obtain sufficient equipment to support all reactors at a given site simultaneously. The second order requires the plants to install enhanced equipment for monitoring water levels in each plant’s spent fuel pool. These two orders apply to every commercial nuclear power plant, including those under construction, as well as the recently licensed Vogtle reactors.

The third order applies only to US boiling-water reactors that have Mark I or Mark II containment structures. These reactors must improve venting systems (or for the Mark II plants, install new systems) that help prevent or mitigate core damage in the event of a serious accident.

The NRC will also issue a detailed information request to every operating US commercial nuclear power plant, and certain parts will apply to reactors currently under construction or recently licensed. The request covers several topics, including:

• Re-analyzing earthquake and flooding risks using the latest available information;

• Conducting earthquake and flooding hazard ‘walkdowns,’ where skilled engineers closely examine a plant’s ability to meet current requirements;

• Assessing the ability of a plant’s current communications systems and equipment to perform under conditions of onsite and offsite damage and prolonged loss of all ac electrical power; and

• Assessing plant staffing levels needed to fill emergency positions in response to events simultaneously affecting all reactors at a given site.

Each section of the request includes schedules for plants to provide the relevant information to the NRC.