Section 238.751 - Alerters(a) An alerter shall be provided in the operating cab of each Tier III trainset, unless in accordance with paragraph (e) of this section the trainset operates in a territory where an alternate technology providing equivalent safety is installed, such as redundant automatic train control or redundant automatic train stop system.(b) Upon initiation of the alerter, the engineer must acknowledge the alerter within the time period and according to the parameters specified by the railroad, as approved by FRA, in order for train operations to remain under the full control of the engineer.(c) If the engineer does not acknowledge the alerter as specified in paragraph (b) of this section, at a minimum a retrievable full service brake application shall occur until the train has stopped, unless the crew intervenes as described in paragraph (d) of this section.(d) To retrieve the full service brake application described in paragraph (c) of this section, the engineer must acknowledge the alerter and activate appropriate controls to issue a command for brake application as specified by the railroad and approved by FRA.(e) If an alternate technology to the alerter is used, the railroad shall conduct an analysis that confirms the ability of the technology to provide an equivalent level of safety. This analysis shall be approved by FRA.