At approximately 10 p.m. on May 22, 2023, a nineteen-year-old man with white supremacist sympathies attempted to drive a mostly empty, large U-Haul truck close to the White House. Security bollards surrounding Lafayette Square, a park that lies north of and adjacent to the White House, prevented the truck from entering the park.
The failed attack serves as a reminder that properly installed, high quality security bollards can be effective against vehicle attacks. Bollards are fixed, retractable, or removable short posts installed on a street or sidewalk to prevent intrusion by vehicles. The attack also highlights the importance of stand-off distance, which is a physical buffer for protected facilities and people. In this case, bollards surrounding Lafayette Square enhance the vehicular stand-off distance north of the White House.
However, the attack also hinted at the potential disruptiveness of a vehicle-borne improvised explosive device (VBIED), or home-made bomb, threat—regardless of the actual presence of explosives—in urban areas such as Washington, D.C. Our interactive Sapphire map below allows you to move around, toggle on/off features such as the shelter-in-place zone and preferred evacuation distance, and click on facilities featured. The zones/distances are based on the precise location of the U-Haul truck crash.
For example, a small delivery truck can be expected to hold 4,000 pounds of explosives (TNT equivalent). As depicted in our Sapphire map, the mandatory evacuation distance for that amount of explosives is 640 feet (the red area on the map), according to the U.S. Department of Homeland Security and the FBI. People within this distance—sometimes referred to as the building evacuation distance—must evacuate, whether they are inside or outside of buildings (it is based on the ability of typical U.S. commercial construction to resist severe damage or collapse following a blast).
After the U-Haul truck crashed, officials reportedly evacuated the Hay-Adams and Sofitel hotels, the former of which is across the street from Lafayette Square and well within 640 feet of the incident.
Between the edge of the 640-foot mandatory evacuation distance and 3,799 feet is the shelter-in-place zone (the yellow area on the map) for the equivalent of 4,000 pounds of TNT explosives. Within this area, people should seek shelter immediately inside a building away from windows and exterior walls.
Beyond 3,799 feet is the preferred evacuation distance for evacuation of people in buildings and mandatory for people outdoors. In other words, if you are outdoors, you should be at least 3,800 feet from a delivery truck suspected or confirmed to be filled with explosives.
The population density—hotel guests, apartment dwellers, and government and private sector employees—within this preferred evacuation distance highlights the vulnerabilities and potential disruptions that operational explosives or even inert/hoax devices can cause in any major city. In the District of Columbia, the negative symbolism of such shelter-in-place and evacuation orders would exacerbate actual disruptions, especially during business hours. The White House, U.S. Treasury Department, U.S. Secret Service (USSS) headquarters, the USSS Counterfeit Currency Processing Facility (CCPF), and U.S. Customs and Border Protection are some of the federal government organizations that would be located within the 3,799-foot shelter-in-place zone if the U-Haul truck had suspected or confirmed explosives.
The Oklahoma City bombing on April 19, 1995 provides an example of the destruction that can result from an explosives-laden rental truck. Over 5,000 pounds of explosives (estimated to be the equivalent of 4,000 pounds of TNT) in a 20-foot Ryder rental truck, which targeted the A.P. Murrah Federal Building, killed 168 people and injured 500 more. More than 300 nearby buildings were damaged or destroyed.
