In Harbin v. Jamestown Village Joint Venture, 16 Va. App. 190, 428 S.E.2d 754 (1993), the Court explained the "special errand rule." The special errand rule may be stated as follows: when an employee, having identifiable time and space limits on his employment, makes an off-premises journey which would normally not be covered under the usual going and coming rule, the journey may be brought within the course of employment by the fact that the trouble and time of making the journey, or the special inconvenience, hazard, or urgency of making it in the particular circumstances, is itself sufficiently substantial to be viewed as an integral part of the service itself. Id. at 193-94, 428 S.E.2d at 756.