Which two gases commonly fail the TSI test?

The correct answer highlights carbon monoxide and hydrocarbons as the two gases that commonly fail the TSI (Transient Stability Index) test.

Carbon monoxide is a colorless, odorless gas that can be produced from incomplete combustion processes. Elevated levels of carbon monoxide can indicate inadequate air-fuel mixtures, malfunctioning combustion equipment, or issues related to fuel quality, all of which can lead to environmental concerns and health hazards.

Hydrocarbons, which include a wide range of organic compounds, are also significant pollutants that can arise from vehicular emissions, industrial processes, and fuel evaporation. They can lead to the formation of ground-level ozone, which can have detrimental effects on air quality and human health.

The presence of high levels of these gases typically signifies inefficient combustion and the potential for adverse environmental impacts, which is why they are monitored closely and identified as common failures in this particular test.