Final answer:
The answer addresses whether standpipe systems must have lined hose according to laws existing before January 1, 1981. It highlights the need to refer to specific building safety and occupational health regulations to accurately answer the question.
Step-by-step explanation:
The question pertains to whether standpipe systems installed before January 1, 1981 must be equipped with lined hose for use by employees. This is a regulation that falls under legal requirements, particularly in areas such as building safety and occupational health. However, without specific reference to the code or standard, such as the Occupational Safety and Health Administration (OSHA) regulations, it cannot be definitively answered as true or false. It is important to refer to the precise legal stipulations and amendments at the time to determine the requirements for standpipe systems prior to 1981.