Do the Road Transport (Working Time) Regulations 2005 cover occasional mobile workers?

On some occasions non-mobile workers, such as warehouse workers and mechanics, will drive vehicles within the scope of the EU drivers' hours rules. Such occasional mobile workers will be subject to the Working Time Regulations 1998 (SI 1998/1833) and not the Road Transport (Working Time) Regulations 2005 (SI 2005/639). An occasional mobile worker is defined as one who does less than 11 days' work under the drivers' hours rules during a reference period that is shorter than 26 weeks or less than 16 days' work under the rules where the reference period is 26 weeks or longer.