Safety systems take many forms. They range in complexity from very simple, manually operated systems to very complex, automated systems.
Home Safety Systems
Most accidents occur at home because households do not have formal safety programs that both heighten awareness and control behavior. Perhaps the most important home safety system is the smoke detector. At first glance, the smoke detector appears to be simply a small, mysterious box, but it is a safety system. The smoke detector receives input. Sometimes the input is fresh air, and sometimes the input is smoke. The process involves determining whether or not smoke is present. This is typically accomplished by a reduction in electrical current caused by the smoke as it neutralizes charged particles in the sensor. If smoke is present, there is a change in the current at the sensor. If smoke is not present, then there is no change. The output is a loud alarm if smoke is detected. At first glance, it appears that no feedback is provided by the smoke detector safety system. However, if the battery starts to fail, the unit will begin to sound a beep to warn the household that the battery needs changing.
Public Safety Systems
We rarely give a thought to some safety systems. A stop sign is a very simple thing. It is very familiar to us as simply one component in an overall traffic safety system. Certainly, a very obvious and more complex part of that system is the school bus.
The purpose of the school bus--its output--is delivering school children safely to and from school. The school bus is a rolling collection of process and feedback. First of all, the school bus is colored "safety yellow," and its letters, "School Bus," are at least eight inches tall. As a system, a school bus processes people. In order to warn other traffic that a stop is coming up, the bus's lights flash yellow and then red. A flashing stop sign swings out to tell other traffic to stop, and a safety gate swings out to keep children from walking too close to the front of the bus. Often, buses have video cameras to provide feedback. If students misbehave on the bus, or if traffic passes the bus while it is loading or unloading, then officials will find out and correct the safety violations.
Teaching Safety Systems Awareness
Safety is basically the process of communicating well about hazards. Safety awareness is very important for all children. A student's ability to understand the concept of "system" is also important, and perhaps prerequisite, to understanding the complexity of safety systems. Standard Two, Benchmark B of Standards for Technological Literacy: Content for the Study of Technology (ITEA, 2000) states, "Systems have parts or components that work together to accomplish a goal" (p. 34). What could students read about that will help them understand systems as a concept? What could students write about? Following is a way to teach reading, writing, and systems in the context of safety.
There are many kinds of safety systems we use every day, from stop signs to smoke detectors. It's important that children can recognize and be aware of what makes up a system, whether simple or complex. …