People performing these tasks must be provided with the means to get themselves and any equipment they require onto the roof with no risk, or minimal risk of fall or injury.
Working at height. Providing people with a suitable work platform for the task being undertaken reduces the risk of injury from falling from machinery and equipment. Often safe access equipment, made available during installation of machinery and/or equipment, is removed after commissioning.
Machines are used broadly in the field of mechanics. The word mechanical refers to the work that has been produced by machines or the machinery. It mostly relates to the machinery tools and the mechanical applications of science.
Equipment has a wider definition, which basically refers to things needed for a certain task. They act as a set of facilities used in the mechanical works or any other works. The equipment can also be said to be a set of tools used by a human being for a specific task.