There are three distinct types of muscles: skeletal muscles, cardiac or heart muscles, and smooth (non-striated) muscles.
HVAC technicians are responsible for the installation, maintenance and repair of heating, ventilation and air conditioning (HVAC) systems. As an HVAC technician, your job duties may include inspecting existing systems and making recommendations intended to improve the efficiency and/or safety of that system's performance. HVAC-R techs may also work on refrigeration systems.
Elevator installers and repairers install, fix, and maintain elevators, escalators, moving walkways, and other lifts. Duties. Elevator installers and repairers typically do the following: Read and interpret blueprints to determine the layout of system components and to select the equipment needed for installation or repair