https://www.epa.gov/ejscreen/overview-demographic-indicators-ejscreen 

There are seven demographic indicators and a demographic index:

1. People of color:
   • The percent of individuals in a block group who list their racial status as a race other than white alone and/or list their ethnicity as Hispanic or Latino. That is, all people other than non-Hispanic white-alone individuals. The word "alone" in this case indicates that the person is of a single race, not multiracial.
2. Low-income:
   • The percent of a block group's population in households where the household income is less than or equal to twice the federal "poverty level."
3. Unemployment rate:
   • The percent of a block group's population that did not have a job at all during the reporting period, made at least one specific active effort to find a job during the prior 4 weeks, and were available for work (unless temporarily ill).
4. Linguistic isolation:
   • Percent of people in a block group living in linguistically isolated households. A household in which all members age 14 years and over speak a non-English language and also speak English less than "very well" (have difficulty with English) is linguistically isolated.
5. Less than high school education:
   • Percent of people age 25 or older in a block group whose education is short of a high school diploma.
6. Under age 5:
   • Percent of people in a block group under the age of 5.
7. Over age 64:
   • Percent of people in a block group over the age of 64.

EJScreen includes an index that is based on the above demographic indicators:

• Demographic Index is based on the average of two demographic indicators; low-income and people of color.