Computer Put In Vehicle of Haz-Mat Unit
A computer portable enough to fit on the apparatus seat is carried by our hazardous materials response team. On the scene anywhere, it can provide ready reference to information on thousands of materials.
The Hillsborough County, Fla., Fire Department established the special response team in 1979 and began to equip a vehicle with useful equipment. One problem was storing and handling the many necessary books with technical information on hazardous materials. A common solution or rather compromise—has been to select a limited number of the better publications and put them somewhere on the apparatus as a mobile library.
There are some disadvantages with this solution. For example, some good information had to be left behind after any selection. With a particular chemical, the text from a number of the books would have to be looked up and compared or combined for a full description. Handling the books and looking through indexes and thousands of pages would take too long. Pages would soil and tear, and the visibility of small print at night would be difficult.
We began to look at low-cost microcomputers for compact storage, rapid sorting and an easily readable display for the selected information. This had to be the answer for us, but it was not so simple as originally perceived because there was much to learn about microcomputers.
Before we could proceed we had to answer these questions: Should we use a split system with the main computer at the communications center and a keyboard/printer on the apparatus with radio access? Or should we use a selfcontained on-board computer system, which would require the team members to be more actively involved?
Since cost was a great factor, we chose to experiment with the self-contained microcomputer. In selecting the type of on-board system to use, three basic criteria were considered. The system had to be:
- Relatively inexpensive
- Small in size
- Simple to operate
Our system cost less than $2000, including mobile installation. It is a TRS-80 computer from Radio Shack, with 32K memory (very roughly, 32,000 characters). Other models, with less memory capacity and cassette tape memory storage, were available at lower cost—but we wanted the flexibility and access speed provided by our disk memory storage.
Our microcomputer system did present some minor problems in converting to mobile application (such as providing the proper electrical line feed), but they were quickly overcome.
Software solution
Programming was the next item for selection. There are many software packages available that were already programmed for inventory control, accounting and other file-and-access uses. We could find no ready-made software package, however, designed to meet our special needs. Instead of adapting an existing program to our operation, we chose to create our own.
Not being programmers, we sought assistance from outside agencies who use computer systems on a large scale. With the help of a few interested computer enthusiasts, we were able to produce a suitable program for indexing, storing and retrieving hazardous materials information—in seconds.
One disk—several books
The contents of several books fits on a single 5 ¼-inch-diameter disk that looks like a flexible phonograph record. To load more information into the available memory, we developed a special indexing system to use our own terminology codes and abbreviations. We are in the process of rewriting a more sophisticated program to allow cross referencing and cross indexing.
We are also experimenting with a mobile telephone interface which will allow our microcomputer to communicate nationwide with other computers’ information banks. The microcomputer is already to do many more useful things as we learn more about it.
