In early August 2020, strong storms blew through St. Louis, causing power outages and other disruptions. A friend shared a story about the storm causing a modem to burst into flames spectacularly, then asked if it was real. It probably was. It’s entirely possible for a storm to damage a modem, sometimes in dramatic fashion.
Although it’s unusual, it is entirely possible for a storm to damage a modem. The damage can be partial, or complete.
The danger of storms to modems
Usually the storm damage to modems isn’t as spectacular as sending an AC adapter flying across the room or the AC adapter or modem bursting into flames. It’s usually subtle. The modem stops working, or performance degrades, or it becomes less reliable.
The damage can come directly or less directly. When the failure is dramatic and noticeable, involving flames or shooting across the room, there was a direct lightning strike somewhere close. These happen from time to time. When I was growing up, we lost our first VCR to a lightning strike. It’s not just modems. Anything that connects to your electrical line, phone line, or cable line is susceptible. So it’s no coincidence our VCR took a hit decades ago.
It happened with dialup modems too. Sometimes the whole modem stopped working. Sometimes it was just the fax portion. Some people rarely used the fax portion, so it was unclear why the fax portion stopped working.
One advantage of fiber Internet is since the data line is buried underground and uses light instead of electricity, your modem has one less path to sustain damage.
Do surge protectors protect against storm damage?
Surge protectors do provide some amount of protection against storms, but keep in mind if you sustain a direct lightning hit, no surge protector is powerful enough to protect against that. You also need protection for your data line, not just your power line. The surge protector sacrifices itself to protect your equipment. There’s always a light that indicates whether you’re protected. When that light goes out or starts blinking, it’s no longer supplying protection, though it will continue to provide power. I have surge protectors from 30 years ago that still function as power strips, they just don’t provide any protection anymore.
David Farquhar is a computer security professional, entrepreneur, and author. He started his career as a part-time computer technician in 1994, worked his way up to system administrator by 1997, and has specialized in vulnerability management since 2013. He invests in real estate on the side and his hobbies include O gauge trains, baseball cards, and retro computers and video games. A University of Missouri graduate, he holds CISSP and Security+ certifications. He lives in St. Louis with his family.