With power out in parts of Cambridge, the result of a powerful spring storm, it’s unclear how many people can access power-outage information from the city’s power provider, Nstar, on its website.

There are about 15,000 people without power across Eastern Massachusetts, with “no firm time” set for when it will be restored, said Walter Salvi, a company spokesman. There were already extra crews working in case of an outage, but even more were brought in for a “storm of such magnitude.”

Cambridge is the third hardest-hit area after the Framingham and Waltham areas, Salvi said.

For what it’s worth — meaning, presumably, for people with charged laptops, mobile devices or power generators of their own — here is advice from Nstar:

If the power goes out

  • Call Nstar Electric at (800) 592-2000 to report your outage.
  • Stay clear of all fallen tree limbs and electrical wires as well as anything they are touching — such as puddles and metal fences.
  • Disconnect appliances that will go on automatically when the power is restored. These include refrigerators, stoves, furnaces and water heaters.
  • Turn off appliances such as washers, dryers, computers and TVs. Once power is restored, turn appliances back on one at a time to avoid a power surge.
  • If using candles or matches, be extremely careful.
  • Food in your refrigerator will keep for six to nine hours, and food in your freezer will keep between 36 and 48 hours. It will help to minimize the number of times the door is opened.

Nstar restoration efforts

Our advanced, computerized control system often gives us first notification of a large power outage. We also get reports from public safety agencies and local police and fire departments.

Nstar also depends on customers to report outages using our toll-free number — (800) 592-2000. Smaller outages can sometimes go undetected by the automated parts of our system.

Our specialized computer system allows dispatchers to analyze and take care of many problems electronically, which can reduce the duration of an outage. If the problem cannot be corrected in the control room, a crew will be dispatched.

In the event of a major storm, Nstar implements an emergency plan of operation which places the efforts of the entire company behind power restoration 24-hours a day. We will try to restore electric service to the maximum number of customers in the shortest possible time.

Nstar is in constant communication with government representatives, town officials and the media throughout any outage; therefore you may be able to receive updated information through your battery-operated radio.

Frequently asked questions

What should I do when my power goes out? First, make sure the switches of your circuit breaker are all in the on position or that you haven’t blown any fuses. If everything appears to be fine, then call Nstar at (800) 592-2000 to report the outage.

What type of situations tend to create service interruptions? While interruptions can be caused by a variety of different situations, high winds, heavy snow and ice pose significant challenges for our wires. Other factors might also cause outages in your area, such as an automobile striking a utility pole. For customers in cities and towns served by an underground system, flooding can also cause equipment damage in manholes.

Why don’t I see Nstar crews working on my street? Because of how our electric system is designed, your outage might not necessarily be caused by a problem on your street, or even a nearby street. Even if you don’t see crews or Nstar vehicles working near your home, Nstar is working hard to have your power restored as quickly as possible.

I saw an Nstar truck but they’re gone now. My power has not been restored. Is somebody coming back? During emergency situations Nstar will often send out a special crew to find out exactly where the problem is, what kind of work needs to be performed and most importantly to make sure the area is safe. Those workers then make sure the right type of crew is sent to the scene that is qualified to do the necessary repair work. Also, keep in mind we might find the problem is in an area not near your home.

What might cause a delay in restoring my power? Often Nstar is impeded by obstacles blocking access to our power lines. Things such as illegally parked cars, blocked roads, unplowed or flooded streets, downed trees or other dangerous situations slow our response time in repairing damage to our system. Conditions throughout our system also might cause delays. For instance, several small, scattered outages are more time consuming to repair because they entail more time consuming house-to-house stops to reconnect lines to individual homes.

How does Nstar prioritize restoration efforts during a significant emergency situation? Nstar implements an emergency plan of operations that places the efforts of the entire company behind power restoration 24-hours a day. We will try to restore electric service to the maximum number of customers in the shortest possible time.

Update: Service was restored to many within a couple of hours of the outage, and to all but a few — “literally a few” — by Monday morning, said Nstar spokesman Michael Durand on Monday. The remaining handful of problems was solved by late morning.