Consider safety, health issues in Y2K plans

Occupational safety and health professionals have been warned that the Y2K computer problem will pose threats to worker safety, and now the National Institute for Occupational Safety and Health (NIOSH) in Cincinnati is offering specific advice on how to respond.

The Y2K problem, which threatens to cause havoc when some computers fail to recognize the two-digit year "00," can affect a host of safety systems. In a special advisement issued recently, NIOSH urges occupational health professionals to pay special attention to any equipment or systems that contain embedded microchips.

"A major problem is that embedded micro-chips and software with date-dependent functions are ubiquitous in process control operations, controlling everything from power grid systems to ventilation systems," NIOSH warns. "The difficulty lies in identifying which components contain date-dependent functions and which software applications use yearly dates as data points. Few organizations have an inventory of their computer program source codes or even the subcomponents of their process-control systems."

Typically, process-control components are linked into larger systems involving a feedback mechanism. This results in inter-connected systems, so that when one unit fails, they all fail, not unlike a string of Christmas lights. Finally, the problem can occur at any level of the system: the computer clock, the basic input/output system (BIOS), the operating system, the application software, or the data held.

NIOSH provides these examples of systems that may fail and affect the safety and health of workers: The electrical supply, including backup lighting and generators, could fail and hamper entry and exit from work sites. Fire control systems could fail and leave workers unable to know of a fire and fire location. Valve control systems could malfunction and pose dangers from hazardous materials. Inactive security systems and cameras could leave workers without the ability to assess potential dangers.

In general, systems that operate using embedded microchips typically fall into one of these four categories:

1. Individual microprocessors (e.g., temperature sensors, smoke and gas detectors, circuit breakers, etc.).

2. Small assemblies of microprocessors with no timing functions (e.g., flow controllers, signal amplifiers, position sensors, valve actuators, etc.).

3. Subassemblies with a timing function (e.g., switches/controllers, telephone exchanges, elevators, data acquisition, monitoring, and diagnostic). Sensors in these subassemblies systems usually send data to computers that run database programs. Y2K failures may occur within or between subassemblies and even before the year 2000 because the system may project a future action that would not be recognized.

4. Computer systems used in manufacturing or process control, which also usually include embedded microchips. System failures would be expected because the software and hardware are usually based on commercial data processing languages that were developed years ago, such as COBOL and FORTRAN.

NIOSH advises that items in categories 1 and 2 are least likely to fail. Items in category 4 are most likely to fail. NIOSH says the highest priority in the event of Y2K failure should be given to those systems that have the greatest impact on the safety and health of workers, as well as the public, followed by those systems that have an impact on business operations. The task can be made difficult when the two systems are intertwined in production-oriented industries.