A drafting guide for drawing horizontal lines.

Hanging "Do Not Operate" tags on and locking out equipment to ensure that is not operated while maintenance or inspection is carried out.

A tool used to cut internal screw threads.

The measure of intensity and quality of heat.

A fitting that indicates the temperature and pressure of the water leaving a hot water boiler.

A temporary magnet is one in which the domains do not remain aligned after the magnetizing force is removed.

Forces in tension, or tensile forces, are forces that are acting directly away from each other. They tend to pull the material apart.

A device, often equipped with a keyboard and a video display, through which data or information can enter or leave a computer system.

The ratio of heat absorbed by the boiler to heat available in the fuel.

Heat energy.

The production of electricity by using a fossil fuel.

Oil used as a heating medium in a thermal oil heating system.

A temperature-sensing device that produces an electrical signal in proportion to the temperature change.

A device used to measure the temperature of a substance.

A device that controls the input of heat energy to maintain the pre-set temperature in the space being heated.