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Categories and Emission Limits Revised for Air Pollutants from Stationary Sources

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To deter unscrupulous operators from emitting harmful air pollutants, on 3 August the EPA announced the revised categories and emission limits of hazardous air pollutants from stationary sources. This amendment adds 18 new categories of hazardous air pollutants and their respective emission limits and tightens emission limits for one existing pollutant, bringing the total number of regulated pollutants to 23 in the hope of better protection of the public’s health. Emission limits for hazardous air pollutants from illegal exhaust pipes have also been newly added to further penalize illegal discharges.

In 2018, the Air Pollution Control Act (空氣污染防制法) was amended with the addition of Article 53. It states, "If public and private premises with stationary pollution sources that emit air pollutants through exhaust pipes violate the standards for air pollutant emission limits which are determined pursuant to Article 20 Paragraph 2 and thereby cause human death or harm to health, they shall be punished by a maximum of seven years of imprisonment and may be fined a sum of no less than NT$1 million and no more than NT$15 million." Therefore, "standards for air pollutant emission limits" serve as the basis for determining whether businesses may be penalized as stipulated in this article.

This amendment categorizes emission limits into two types: emissions through "exhaust pipes" and those through "illegal exhaust pipes." This differentiation was made in response to recent inspections that revealed unscrupulous businesses resorting to alternative discharge activities, such as rerouting, to evade detection during inspections. Discharges through “illegal exhaust pipes” refer to exhausts from production processes, collected by gas-gathering equipment within facilities, that are released through facility ventilation holes, air vents, or unpermitted emission outlets instead of regular, approved exhaust pipes. The revision aims to impose strict penalties on such activities that deliberately pollute the air and pose a threat to the public’s health.

The emission limit of an air pollutant is set by calculating emission concentration in exhaust pipes using the environmental risk index as a basis, in combination with an air dispersion model. An air pollutant’s environmental risk after being emitted from exhaust pipes is quantified as 1×10-4 (0.0001 times) of the highest concentration of the pollutant on ground surfaces of peripheral boundary. This is the upper threshold that an individual is able to withstand under long-term exposure to any given air pollutant in the atmosphere throughout an individual’s whole life, and human health is at risk if the concentration is above such a threshold. Additionally, a pollutant’s emission limit through illegal exhaust pipes is set at 1% of that through legal exhaust pipes in consideration of the testing and sampling methods applicable to illegal exhaust pipes and the unavoidable dilution effects during the sampling process.

To provide businesses with an appropriate and reasonable timeframe for improvement, revised emission limits for certain air pollutants from exhaust pipes will not come into effect until 1 July 2024. These include 19 air pollutants, items 5 to 23 listed in the revision’s Table 2, such as trichloroethylene, mercury and its compounds, arsenic and its compounds, and nickel and its compounds. As for the remaining four air pollutants -- namely dioxin, vinyl chloride monomer, cadmium and its compounds, and lead and its compounds -- their emission limits, previously set and not adjusted in this revision, will become effective from the date of announcement. Furthermore, the amendment has newly added emission limits for discharges of 23 air pollutants, including dioxin, from exhaust pipes, and they will come into effect on the date of announcement. This is due to consideration that emission limits for illegal exhaust pipes are set to regulate unlawful emissions by unscrupulous businesses attempting to evade inspections and testing, and deter environmental crimes such as illegal discharges of hazardous air pollutants.

Excerpt from Major Environmental Policies, August 2023

Ministry of Environment