According to Washington Administrative Code 468-38-100(16):

For hire certified pilot/escort vehicle operators are required to have insurance to conduct the duties associated to this rule:

(a) One hundred thousand dollars for bodily injury to or death of one person in any one accident;

(b) Three hundred thousand dollars for bodily injury to or death of two or more persons in any one accident; and

(c) Fifty thousand dollars for damage to or destruction of property of others in any one accident.

Satisfactory evidence of the insurance shall be carried at all times by the operator of the pilot vehicle, which evidence shall be displayed upon request by a law enforcement officer.