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- 26 - Rule Interpretation

Table 1 indicates that the crewmembers of trains 416 and 720 had a problem in interpreting Rules 285, 291, and 292, which concern the meaning of several aspects displayed by the automatic—block signal system. When questioned about what is required by a yellow aspect, five crewmembers, including the engineer of 720, responded with maximum train speeds. Although the speeds given varied, each crewmember failed to recognize that a signal showing a yellow aspect requires that a train be prepared to stop at the next signal.

Two of the four crewmembers questioned about the meaning of a red aspect displayed by a signal with a number plate also answered with maximum speeds. Such a signal aspect, however, also requires that a train be prepared to stop short of train, obstruction, etc.

There were two incorrect responses to the question regarding the meaning of a red aspect displayed by a signal without a number plate. The crewmembers who answered incorrectly combined the meaning of a stop indication, i.e., a red aspect displayed by a signal without a number plate, with the restricted proceed indication.

The meaning of Rules 285, 291, and 292 is explicit. There should be no need for more detailed interpretation. The incorrect interpretations by the crewmembers suggest that (1) the rule training, examination, and enforcement activities of the ICG were inadequate and (2) a rule that contains dual requirements or requirements similar to those contained in other rules can result in incomplete understanding.

This accident, however, also involved rules whose meaning or whose applications were unclear. Although they did not dispute the meaning of Rule 515, employee representatives at the Safety Board's public hearing argued that Rule 99(a) was an integral part of Rule 99 and that, therefore, Rule 99(a) relieved the crewmembers of 416 of the responsibility of flagging. However, this interpretation was contrary to the understanding demonstrated by the crewmembers in the 1970 examinations, when they were questioned about Rule 515 without reference to Rule 99(a).

Representatives of the railroad, on the other hand, maintained that Rules 99 and 99(a) were separate rules. They stated that the reference to Rule 99 in Rule 515 applied only to flagging. They further argued that 99(a) was not even involved, since when train 416 reversed direction, the "following movement" became an opposing movement. The ICG representatives, however, also argued that Rule D-99 did not apply, saying that 416 was not running against the current of traffic even though it was an opposing movement.