Emergency Vehicle 3 Design Load

[siuceric21]

I am in the process of designing a Storm Water Control Vault that is 80' x 40' x 6' roughly 1 ft below top of paving. The vault is am planning on designing as a one way slab spanning in the 40' direction.
Knowing there is potential fire truck traffic over this box (& semi truck) I looked up wheel loading of fire trucks and came across the below showing a 62,000 max GAWR (Gross Axle wheel loading). My thought is this loading would control over semi-truck loading (for my specific instance), would you agree? It seemed a bit of a shock to me (typically a Buildings Engineer) as HS-20 / HL 93 is talked as the design loading for Bridges but seems to me the 62k tandem axle load would control in certain instances.
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[BridgeSmith]

It looks like that would be somewhat heavier than the unfactored HL-93 Truck or Tandem. However, the HL-93 loading typically gets multiplied by a load factor of 1.75 for design. Since unlike the HL-93, the actual axle weights are known, therefore the uncertainty in the load magnitude is very small. You could reasonably reduce the load factor significantly for the fire engine.

It may also be reasonable to exclude the Lane Load applied simultaneously with the HL-93 Truck or Tandem, since this is an emergency vehicle.