Can a permit to work last for more than 24 hours? What precautions need to be in place for shift handovers?

As a personnel preference, I would recommend 'no' The point of a permit is to have control over high risk areas or work activities i.e. the work area or task being checked at the end of each shift. A permit should last for no longer than the shift allocated to the person(s) carrying out the task i.e. 8, 10, or max 12 hours. You should have a method statement/safe systems of work devised, and use the permit to work as part of the safe systems of work. The main point of the permit, is to ensure total control of a potentially hazardous work area/location. This is, of course, down to the discression of the person issuing the permit, or your company procedures but, what is the point of the permit being issued, if it does not give the issuer piece of mind. See: http://www.hse.gov.uk/pubns/priced/hsg47.pdf

Bragg, Permits to Work can have a duration of more than one day, and documentation I've used/seen includes date time for expiry e.g. a cleaning job with a cherry-picker can last a week The HSE guidance HSG250 doesn't include specific recommendations for extended PtW but the usual precautions apply, particularly the interim checks/visits that the agreed conditions/procedures are being followed, "Paragraph 25. A permit-to-work system will be fully effective only if the permits are co-ordinated and controlled by an issuing or other responsible authority (see paragraph 29), and there is adequate supervision and monitoring of the system to make sure that the specified procedures are being followed. This should include site visits by the issuing authority to check whether the conditions of the permit are being complied with (as a minimum, at start and completion of the task, with interim checks depending on hazard, complexity and duration of task)".