To determine how long the ventilation blower should be operated after fueling, let's evaluate the provided options in detail:
1. More than 10 minutes: This option suggests that the blower should run for a duration greater than 10 minutes.
2. Half an hour to an hour: This option indicates a much longer duration, from 30 to 60 minutes, for operating the blower.
3. At least 4 minutes: This option proposes a shorter duration, a minimum of 4 minutes, for running the blower.
4. One full minute: This is the shortest operation duration among the options, suggesting just 1 minute for running the blower.
Given these options, the correct choice is that the ventilation blower should be operated "more than 10 minutes" after fueling. This ensures that the ventilation is adequate to handle the fumes and maintain safety standards.
