Assessment to determine environmental factors, there is a causal relationship between environmental factors and environmental impact; when to identify the environmental factors and control its impact, in addition to the use of quantitative methods, master all aspects affecting environmental factors and have appropriate assessment are the important ways to identify environmental factors:
a. three conditions: activities, products and services;
b. eight types: water, gas, steam, lees, noise, waste, soil, resources (animals, plants, people, raw materials);
c. three tenses: Now, in the past, the future (potential);
d. three states: normal and abnormal, emergency;
e. six directions: East, West, North and South, on, under or on, under, left, right, before and after;
f. eight pairs of nature: the main and sub, good or bad, light and heavy, slow and urgent, actual and potential, often accidental, controllable and uncontrollable, direct and indirect
g. two periods: long and short.

For the importance of environmental factors, the general judgment: is to divide into major environmental factors and general environmental factors:
(1) legal, regulatory requirements are the major environmental factors;
(2) the original, materials, design and development at the same time meet certain conditions are the major environmental factors;

The significance to identify important degree of environmental factors is that the system requires that environmental factors management department is responsible for the overall control of environmental factors, reporting regularly to the manager representatives the environmental performance of environmental factors. And according to environmental indicators testing requirements, commit the local environmental protection departments to monitor environmental performance of environmental factors (wastewater, such as exhaust emissions) at least once a year, timely dealing with the found problems.