High Explosives (TNT Equivalent)
Threat Description Explosives Mass1
(TNT Equivalent)
Building
Evacuation
Distance2
Outdoor
Evacuation
Distance3
Pipe Bomb 5 lbs. 70 ft. 850 ft.
Suicide Belt 10 lbs. 90 ft. 1,080 ft.
Suicide Vest 20 lgs. 110 ft. 1,360 ft.
Briefcase or Suitcase
Bomb
50 lbs. 150 ft. 1,850 ft.
Compact Sedan 500 lbs. 320 ft. 1,500 ft.
Sedan 1,000 lbs. 400 ft. 1,750 ft.
Passenger or Cargo Van 4,000 lbs. 640 ft. 2,750 ft.
Small Moving Van or
Delivery Truck
10,000 lbs. 860 ft. 3,750 ft.
Tanker Truck 30,000 lgs. 1,240 ft. 6,500 ft.
Semitrailer 60,000 lbs. 1,570 ft. 7,000 ft.

Liquefied Petroleum Gas (LPG Butane or Propane)
Threat Description LPG Mass/Volume1 Fireball
Diameter4
Safe
Distance5
Small LPG Tank 20 lbs. 5 gal. 40 ft. 160 ft.
Large LPG Tank 100 lbs 25 gal. 69 ft. 276 ft.
Commercial or Residential
LPG Tank
2,000 lbs. 500 gal. 184 ft. 736 ft.
Small LPG Truck 8,000 lbs. 2,000 gal. 292 ft. 1,168 ft.

1 Based on the maximum amount of material that could reasonably fit into a container or vehicle. Variations possible.

2 Governed by the ability of an unreinforced building to withstand severe damage or collapse.

3 Governed by the greater of fragment throw distance or glass breakagean the falling glass hazard distance.  These distances can be reduced for personnel wearing ballistic protection.  Note that the pipe bomb, suicide belt or vest, and briefcase or suitcase bomb are assumed to have a fragmentation characteristic that requires greater standoff distances than an equal amount of explosives in a vehicle.

4 Assuming efficient mixing of the flammable gas with ambient air.

5 Determined by U.S. firefighting practices wherein safe distances are approximately 4 times the flame height.  Note that an LPG tank filled with high explosives would require a significantly greater standoff distance than if it were filled with LPG.

Additional information at Kolb's Web Site.  http://tkolb.net