Why do we need to pack vehicles ten metres from the building in hotels and high rise buildings?

To keep the vehicle safe from falling anything  on it(from the buiilding)

To minimize the effect of a blast in case of a explosive device at the same time maintining practical convenience for unloading and avoiding un necessary rush

Dear Andrew

The obvious logic would be to minimize the effect of a blast in case of a explosive device at the same time maintining practical convenience for unloading. 

In case of a van loaded with explosives the lethal air blast disance is200 feet /61 meters now we may not be expecting the whole load to be the same so fi we take a briefcase full then its15 meters. 

'So we would wish to reduce if not totally eliminate the risk, thats whay I can think of.

Hope that clarifies

Regards

Capt Percy Jokhi