OTTAWA -- The City of Ottawa has made public a report into the air quality at the underground Rideau LRT station.
Early in the year, riders began complaining about an unpleasant "rotten egg" smell in the tunnel, which is located deep underground. This was a new odour complaint for the LRT tunnel, as riders had also mentioned a sewage smell in the nearby Parliament Station early on in the Confederation Line's operation.
The rotten egg complaints, however, prompted Rideau Transit Maintenance to hire an outside firm to conduct an indoor air quality assessment. RTM had also suggested stagnant water could have been the source of the smell.
Buller Chrichton Environmental (BCE) conducted the air quality test on Feb. 6, 2020.
In a memo sent Friday, Director of Rail Construction Michael Morgan said the company conducted the test in several key areas of Rideau Station, as identified by RTM.
"Each location was assessed, and measurements were recorded with the IAQ data assessed against key standards for acceptable indoor air quality, Ministry of Labour regulations, and provincial and federal occupational health and safety standards," Morgan said.
In its report, BCE said the investigation observed levels of the following: oxygen, hydrogen sulphide, lower explosive limits of combustible gases, total volatile organic compounds, carbon monoxide, carbon dioxide, and relative humidity.
What the one-day investigation found was, essentially, nothing out of the ordinary.
"No concerns were identified regarding atmospheric hazards of [hydrogen sulphide], [oyxgen] and the lower explosive limits of combustible gases. The air quality observed within the selected locations of the Rideau Station is within the acceptable ranges to satisfy 80% of the occupants," BCE's report said.
The average readings for combustible gases and hydrogen sulphide—a suspected source of the rotten egg smell—were zero. Volatile organic compounds, which can be released from things like paint, glue, and cleaning supplies, came in at an average reading of 1.2 parts per billion, significantly below Health Canada guidelines of 400 parts per billion.
The report also said there were no obvious signs of water damage, mould growth, or other issues that would negatively affect air quality on the day they took the readings.
The report made no recommendations.
