EMFAC-HK Web Based Training

Overview

EMFAC-HK allows users to create various scenarios by geographic area, year, and assorted criteria to show specific sets of emissions data to help illustrate emissions trends.

EMFAC-HK creates these various scenarios using what are called emission inventories.

What is an emission inventory?
A record of the estimated amount of pollutants (commonly measured in grams or tonnes) emitted from a mobile source (e.g., car) into the atmosphere over a specific period (e.g., a day or a year).

The model calculates emission inventories for the following primary pollutants:

• Hydrocarbons (HC). HC can be expressed as TOG (total organic gases), VOC (volatile organic gases), THC (total hydrocarbon), or CH₄ (methane). The THC class includes compounds with H and C atoms only; carbonyls and halogens are not included. The TOG class includes all organic gases emitted into the atmosphere. The VOC class is the same as U.S. Environmental Protection Agency’s VOC (volatile organic compounds) definition, as well as California Air Resources Board's ROG (reactive organic gases) definition, and does not contain compounds exempt from regulation.

• Carbon monoxide (CO).

• Nitrogen oxides (NO_x).

• Carbon dioxide (CO₂).

• Particulate matter (PM). PM estimates are provided for total suspended particulate, particulate matter 10 microns or less in diameter (PM10), and particulate matter 2.5 microns or less in diameter (PM2.5).