CSA R7008-19 – Railway Applications: Noise Emission Limits and Measurement Practices for Rolling Stock

Scope of CSA R7008-19

CSA R7008-19 establishes uniform procedures and limits for measuring and evaluating exterior noise emitted by railway rolling stock operating in Canada. The standard applies to all types of rail vehicles, including electric and diesel locomotives, passenger coaches, freight wagons, light rail vehicles (LRVs), and self-propelled multiple-unit trains. It covers both pass-by noise (vehicle in motion) and stationary noise (vehicle idling or in standstill with auxiliary equipment running).

The scope addresses vehicles operating on standard‑gauge tracks under typical Canadian climatic conditions. The standard is intended for type‑testing of new designs, verification of compliance with noise regulations, and monitoring of existing fleets. Exemptions include maintenance‑of‑way vehicles operated exclusively in work zones and steam locomotives not used in regular passenger service. While CSA R7008‑19 primarily targets open‑air noise, it also provides guidance for tunnel sections and depot areas where applicable.

Technical Requirements

Noise Limits

The standard defines maximum sound pressure levels for both pass‑by and stationary conditions. Limits are specified in A‑weighted equivalent continuous sound pressure level (L_pAeq,T) in decibels (dB(A)). Table 1 summarises the pass‑by limits at the reference distance of 7.5 m from the track centreline and 1.2 m above rail level.

Table 1 – Pass‑by noise limits from CSA R7008‑19 (representative values for illustration).

Stationary noise limits are measured while the vehicle is at idle, all auxiliary systems (cooling fans, compressors, HVAC) running at maximum load. The limit for locomotives is 75 dB(A) at 7.5 m; for passenger vehicles it is 70 dB(A).

Measurement Methods

CSA R7008‑19 details the test site requirements, instrumentation, and procedure for obtaining valid noise data. Key requirements include:

• Microphone placement: Two positions – one at 7.5 m from the track centreline, 1.2 m above rail head; a second optional position at 25 m for far‑field assessment.
• Track condition: Rails must be dry, clean, and free from rail corrugation. Rail roughness shall be measured and reported.
• Meteorological conditions: Wind speed ≤ 5 m/s, no precipitation, ambient temperature between 0 °C and 35 °C. Background noise must be at least 10 dB below the measured rolling stock noise.
• Speed and traction: The vehicle must be at constant speed (±2 km/h) during the pass‑by. Traction power should be set to represent typical operating load (e.g., 50 % notch for locomotives).
• Data processing: A‑weighting, Fast time weighting, 1/3‑octave band analysis. At least three runs per speed condition are required, with results averaged.

Implementation Highlights

Adopting CSA R7008‑19 requires careful planning across vehicle design, qualification testing, and fleet management. Early integration of noise control measures – such as resilient wheels, acoustic enclosures for diesel engines, and optimised cooling fan design – can significantly reduce the effort needed to meet the limits.

For existing fleets, retrofitting noise reduction components may be necessary. Freight wagon brake noise is a particular challenge; the standard suggests using composite brake blocks or disc brakes to lower squeal and rubbing noise. Operators should also inspect rail roughness regularly, as poor rail condition can increase measured pass‑by levels even if the vehicle itself meets the specifications.

CSA R7008‑19 emphasises traceability and repeatability. All measurement equipment must be calibrated to national standards, and test reports must document vehicle configuration, track parameters, weather log, and raw noise data. Many transit authorities now require compliance with this standard as a condition for new vehicle procurement or route access.

Compliance Notes

Compliance verification follows a two‑tier approach: type testing for new vehicle designs, and periodic surveillance testing for in‑service units. The type test must be performed on a representative vehicle of the series, on a compliant test track. The surveillance test may be done on a representative section of the operator’s own network, provided background noise and track conditions meet the standard’s criteria.

Documentation required for a compliance declaration includes:

• Detailed vehicle description (type, weight, power, wheel configuration).
• Test report with all measurement results and uncertainty analysis.
• Evidence of metrological traceability of instruments.
• Weather and track condition log.
• Statement of conformity to the limits.

CSA R7008‑19 is referenced by Transport Canada’s Railway Safety Act and by many provincial noise regulations. Non‑compliance may result in operating restrictions, noise mitigation orders, or rejection of vehicle type approval. An amendment in 2022 introduced stricter limits for LRVs in urban corridors; operators are advised to verify the latest version of the standard.

Frequently Asked Questions

This article is based on CSA R7008‑19 (revised 2019) and related guidance documents. For complete regulatory requirements, always refer to the latest published standard from CSA Group.