In the case of a security guard who works a shift in excess of 6 hours in length, (1) the specific exemption, relating to security and surveillance activities, which allows the employer not to provide a 20-minute rest break during the shift, (a) does not apply in every case where the employer is obliged to ensure that one worker or another is permanently present on site, (b) will only apply (i) to a worker whose own work pattern requires that particular worker to be permanently present throughout his shift, and (ii) even in those cases, only where the employer can show there were objective reasons why a full normal rest break could not have been provided to him, (2) although it will always be possible to provide a full normal rest break to all workers, if money were no object, by hiring extra security guards, if the employer can show that any significant additional cost could have undermined its ability to secure the contract at all and would have threatened the jobs of the security officers or their pay, this factor can provide an objective reason allowing the exemption to apply, and (3) where the exemption does apply, and hence the employer is obliged instead to provide an 'equivalent period of compensatory rest', this alternative requirement will be satisfied if the employer provides, at an alternative time, a break from work which lasts for at least 20 minutes, according to the Court of Appeal in Hughes v Corps of Commissionaires Management.