In 2003, Capitol Metro planned to use non-FRA compliant Diesel Multiple Units (DMUs) as a cost-effective method of starting commuter rail service in the Austin area. This type of vehicle was new to the US market, and there was no existing body of noise and vibration data for use in environmental studies.
HMMH's extensive contacts in the transit industry allowed us to coordinate the measurements for this project with the Ottawa Transit Authority in order to obtain the information required for the analysis. In addition to the environmental analysis of the DMUs, HMMH:
- Provided a summary of the noise and vibration levels of several types of transit vehicles from our extensive data set
- Conducted an analysis to show the relative impacts of each type of vehicle in order to assist Capitol Metro in their planning process
- Quantified the noise and vibration benefits of the DMUs, as compared with traditional commuter rail and LRT
Data from measurements on operating vehicles resulted in significantly fewer impacts than had been documented in a previous assessment based on assumed noise and vibration levels for these vehicles.