Abstract: Safety bar for vehicles, such as fire trucks. A base member is mounted on a permanent frame of the vehicle. A connecting member is pivotally mounted on the base member for rotation in a first plane. A bar is pivotally mounted on the connecting member for rotation in a second plane perpendicular to the first plane. The connecting member can rotate at one direction from a stop position against the base member and the bar can only rotate at one direction from a stop position against the connecting member. The safety bar has a spring connected to hold the bar and connecting members in stop position.

Abstract: A system for injecting chemicals into a fire fighting system of the type using a plurality of water hoses and having a source of water and a source of chemicals. A servo motor system is connected to automatically meter a certain ratio of chemicals into the water supply. The servo motor system is responsive to the total flow to control the chemical pump to pump a certain ratio of chemicals into the water supply even if the total flow varies. Various modifications are disclosed.

Abstract: Automatic scan flow meter means for systems of the type supplying a plurality of lines. A plurality of flow meters are each connected to a line and to a control panel. Display means are mounted on the control panel. Scanning circuit means are connected to scan the flow meters and sequentially display the flows from the flow meters.

Abstract: A system for injecting chemicals into a fire fighting system of the type using a plurality of water hoses and having a source of water and a source of chemicals. A servo motor system is connected to automatically meter a certain ratio of chemicals into the water supply. The servo motor system is responsive to the total flow to control the chemical pump to pump a certain ratio of chemicals into the water supply even if the total flow varies.

Abstract: Flow measuring means in a pipe having turbulent flow. A chamber is inserted in the pipe. The chamber having a diameter substantially larger than the diameter of the pipe. A flow meter is mounted in the pipe downstream from the chamber. The chamber substantially reduces turbulence in the pipe and provides a reliable flow measurement.