Any incident that produces a large number of injured persons requiring emergency medical treatment and transportation to a medical facility. The exact number of patients that makes an incident mass casualty" is defined by departmental procedures and may vary from area to area.

An alarm system in which a local fire-alarm system triggers a fire alarm box (the master box) to signal the fire condition to a central monitor.

A large nozzle, either portable or fixed to a pumper, capable of throwing large amounts of water relatively long distances.

A volunteer fire department, located north of Syracuse, NY, credited with the invention of the Mattydale Lay. The Mattydale Lay is often simply referred to as a "Mattydale" or (now) a "Cross Lay". The engine on which the Mattydale was invented and installed is currently on display at the FASNY museum

The concept of storing preconnected Attack Lines on an engine, as well as storing them such that they are presented at the sides of the apparatus instead of the rear. Commonly called a Cross Lay, the technique allows for rapid deployment of attack lines from either side of the apparatus.

Hand tool used in fireline construction, consisting of a combination rake and hoe.

The way out of a building during an emergency; may be by door, window, hallway, or exterior fire escape; local fire codes will often dictate the size. location and type according to the number of occupants and the type of occupancy.

A hose with diameter between 2 1/2 and 4 inches.

Extinguishing or removing burning material near control lines, felling snags, and trenching logs to prevent rolling after an area has burned, to make a fire safe, or to reduce residual smoke.

Measuring device designed to indicate concentrations of four selected gases, such as oxygen, carbon monoxide, volatile organic compounds, hydrogen cyanide, etc.

A request by an incident commander for additional personnel and apparatus. Each department will vary on the number of apparatus and personnel on each additional alarm.

An agreement between nearby fire companies to assist each other during emergencies by responding with available manpower and apparatus.

Cross-jurisdictional assistance with emergency services by pre-arranged agreement.