What must be done to a ladder placed against a roof so that it meets safety requirements?

To ensure a ladder placed against a roof meets safety requirements, it is essential that the ladder extends at least 1 meter above the roof edge. This guideline is crucial because it provides adequate handhold support for individuals climbing up and down. Having that additional height helps prevent accidents by ensuring that users can grab onto the roof securely and maintain stability as they transition between the ladder and the roof. Proper extension also reduces the risk of slipping, as it allows for a safe and controlled access point.

Other options do not meet the established safety standards. Securing the ladder to the roof, while a good practice, is not a primary requirement and may not always be feasible. Positioning the ladder directly against the edge is unsafe as it increases the risk of a fall. Lowering the ladder to ground level does not fulfill the need for safe access to elevated areas. Overall, having the ladder extend above the roof edge is the most critical factor in maintaining safety for users.