Ladder Locks 3 : The mechanical locks or pawls that prevent movement of the sections of an aerial device when the power is shut off or in the event of loss of pressure in hydraulic circuits
NFPA 1911 Standard for the Inspection, Maintenance, Testing, and Retirement of In-Service Automotive Fire Apparatus, 2007 ed. https://www.iafc.org/files/1EVM/evms_NFPA1911_1071 andEVT.pdf, (Std: Insp, Maint, Tst and Retirement of In-Srvc Automotive Fr Aptus - Amer) {415 NFC}