10-23-2013 Council Agenda - Laserfiche WebLink

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�+G 5 Guide to the Quiet Zone Establishment Proces Public Safety Considerations Because the absence of routine horn sounding increases the risk of a crossing collision, a public authority that desires to establish a quiet zone usually will be required to mitigate this additional risk. At a minimum, each public highway —rail crossing within a quiet zone must be equipped with active warning devices: flashing lights, gates, constant warning time devices (except in rare circumstances) and power out indicators. In order to create a quiet zone, one of the following conditions must be met 1. The Quiet Zone Risk Index (QZRI) is less than or equal to the Nationwide Significant Risk Threshold (NSRT) with or without additional safety measures such as Supplementary Safety Measures (SSMs) or Alternative Safety Measures (ASMs) described below. The QZRI is the average risk for all public highway -rail crossings in the quiet zone, including the additional risk for absence of train horns and any reduction in risk due to the risk mitigation measures. The NSRT is the level of risk calculated annual- ly by averaging the risk at all of the Nation's public highway -rail grade crossings equipped with flashing lights and gates where train horns are routinely sounded. 2. The Quiet Zone Risk Index (QZRI) is less than or equal to the Risk Index With Horns (RIWH) with additional safety measures such as SSMs or ASMs. The RIWH is the average risk for all public highway -rail crossings in the proposed quiet zone when loco- motive horns are routinely sounded. 3. Install SSMs at every public highway -rail crossing. This is the best method to reduce to reduce risks in a proposed quiet zone and to enhance safety. SSMs are pre- approved risk reduction engineering treatments installed at certain public highway -rail crossings within the quiet zone and can help maximize safety benefits and minimize risk. SSMs include: medians or channelization devices, one -way streets with gates, four quadrant gate systems, and temporary or permanent crossing closures. Exam- ples of SSMs are shown on the next page. ASMs are safety systems, other than SSMs, that are used to reduce risk in a quiet zone. ASMs typically are improvements that do not fully meet the requirements to be SSMs and their risk reduction effectiveness must be submitted in writing and approved by FRA. FRA strongly recommends that all crossings in the quiet zone be reviewed by a diagnostic team. A diagnostic team typically consists of representatives from the public authority, railroad, and State agency responsible for crossing safety and FRA grade crossing managers. a 5