A Laborer must have a common knowledge of all work performed by building tradespersons because the Laborer is the tender in the industry. Laborers are called upon to operate and maintain power tools such as the chain saw, tamping machine, concrete vibrator, chipping hammer, cutting and burning, demolition, and the use of explosives, mixing for and tending of brickmasons & plasterers, installing sewers, cribbing and sheeting.