Pump-jack

Pump-jack

A pump-jack is type of portable scaffolding system. The scaffold rests on supports attached to 2 or more horizontal posts. The user raises the scaffolding by pumping the foot pedals on the supports. Used in construction.

External links

* [http://www.osha.gov/SLTC/etools/scaffolding/supported/pumpjack.html U.S. Department of Labor entry]


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