The tour is the plant inspection activity;- you check mostly visually, sometimes (if qualified) you check safety valves, leaks, etc...The person in charge with the inspection safety requirements will held a meeting with the field inspectors to review the safety requirements for that inspection activity.
The job is the type of work which may intend to modify the plant equipment and require specialized safety approach and full understanding of the people involved in that job. This will include review of the work permits, review of the local safety requirements, plant section shut-down procedures as appropriate, etc..The person in charge with the job has to make sure that everyone knows precisely what to do, is fully aware of the local safety requirements and is able to complete the job without resorting to the emergency services. That is the scope of the pre-job safety meeting.
Cheers,
gr2vessels