Listen To What The Capitol’s ‘Giant Voice’ Alert System Sounds Like When It Goes Into Lockdown

A fire near the Capitol triggered a booming audible response amid heightened security ahead of President-elect Biden’s inauguration.

byJoseph Trevithick|
U.S. Homeland photo


Downtown Washington, D.C. has been turned into a veritable fortress in the wake of the storming of the Capitol building and ahead of President-elect Joe Biden's inauguration this week, as you can read about more in this War Zone piece from yesterday. Tens of thousands of U.S. military personnel, as well as law enforcement officers, are in place and on high alert. We have now gotten a demonstration of the take-absolutely-no-chances security posture in place in the city after a nearby fire triggered a brief lockdown at the Capitol, complete with loudspeakers blaring a message directing people to shelter in place or otherwise seek cover due to an "external security threat."

The fire in question broke out around 10:00 AM local time near the intersection of 1st and F Streets, Southeast, just over 3,000 feet southeast of the Capitol. The exact cause remains unknown, but the blaze appears to have started at a homeless encampment. D.C. Fire and EMS have already reported that the fire has been extinguished and that there were thankfully no injuries. The U.S. Secret Service says that "there is no threat to the public."

A picture of the fire in Washington, D.C. that triggered a lockdown at the Capitol on Jan. 18, 2021., via Twitter

Capitol Police subsequently said the fire was ignited by two small propane tanks or similar containers exploding. One person was taken into custody, but it's unclear what the charges might be.

However, the fire broke out during a rehearsal for the inauguration, and in the aftermath of the siege on the Capitol on Jan. 6 and subsequent alerts about potential new security threats in the nation's capital, it's clear that no one is taking any chances. Soon after the fire started and smoke started to rise to the west of the Capitol, the building went on lockdown, alarms went off, and a very powerful loudspeaker system began broadcasting a message about an "external security threat" and advising people inside the building to shelter in place and avoid doors and windows, as well as instructing people outside to seek cover. People outside were seen moving quickly away from the complex.

Listen to the loudspeaker siren and message in the video below. It is also linked here if it does not show up.

We don't know the exact loudspeaker system installed at the Capitol, but it seems extremely similar to the "Giant Voice" systems that the U.S. military employs to issue similar alerts at bases at home and abroad. These kinds of systems are modern air raid sirens, with the added ability to play pre-recorded and live messages with high clarity over a massive area. 

The video below shows the test of a Giant Voice system at the U.S. Army's Fort Benning in Georgia last year.

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In apublic news release about nearby Andrews AFB's Giant Voice system, its capabilities were described as such:

"There isn't one person who is the Giant Voice," explained Tech. Sgt. Joseph Brady, NCO in charge of console operations for the Andrews Regional Command Post and 316th Wing Command Post. "In fact, the 113th Wing (D.C. Air National Guard) uses the system as well."

While a few base residents may view the Giant Voice as a nuisance, Sergeant Brady said the system should be viewed as a tool. The command post, the primary command and control node for both the Air Force National Capital Region and the president's base, uses the Giant Voice for mass alert, should the base come under threat of attack or natural disaster. Command post controllers provide situational awareness to the important NCR power projection platform that is Andrews.

"One of the biggest misconceptions about the system is that you can adjust the volume - you can't. A large part of the variation in volume comes from wind direction which impacts the overall sound you hear coming over the Giant Voice - we don't control that," Sergeant Brady explained.

A radio frequency is sent base wide to the Giant Voice speakers strategically placed around the base, which is part of the reason why an echo may be heard when the national anthem is played.

In the case of war, base residents will hear three to five-minute wavering tones, like what is heard in the old-time war movies with a high pitch that then drops to a lower tone and back.

During peacetime, but under threat of severe weather, a mass notification is made to take shelter with a steady tone. Because the surrounding community immediately outside the gates can hear the Giant Voice, as well, lightning warnings are not sounded at Andrews as not to alarm non-military personnel.

"The warning system was working almost too well in that case," said Sergeant Brady. "The decision was made to only sound the Giant Voice if there was severe weather - like a tornado or hurricane - or if the base is under attack. The bottom line is, if you hear the Giant Voice and you do not hear 'This is a test' or 'Exercise, exercise, exercise,' you need to get indoors or take shelter immediately."

Staff on Capitol Hill also got a text message alert from the Capitol Police with a similar message to the one issued via the speakers. This again is akin to how the U.S. military issues alerts about various kinds of threats, even including potential incoming missiles.

"In an abundance of caution following an external security threat under the bridge on I-295 at First and F Streets, SE, Acting Chief Pittman ordered a shutdown of the Capitol Complex," the Capitol Police subsequently said in a statement issued to the media. "There are currently no fires on or within the Capitol campus."

This was further confirmed by the U.S. Secret Service in its statement after the incident was declared over and the lockdown was lifted.

Needless to say, given the current circumstances, together with the images of smoke, people running from the Capitol lawn, and the blaring sirens did raise initial concerns that something serious was going on. Thankfully, that turned out to not be the case in this instance.

At the same time, we now know very well what it will sound like if the Capitol has to go into another emergency lockdown this week due to any other potential security threats.

We will update this story as more information becomes available.

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