That will include ensuring websites, mobile apps and digital textbooks contain accessible text, images, sounds, videos, controls, animations and more. The rule sets the Web Content Accessibility Guidelines (WCAG) Version 2.1, Level AA, as the technical standard for compliance. WCAG is widely used across the world and in multiple languages, according to the Bureau of Internet Accessibility, a company that helps companies make their information accessible.

The Justice Department said it expects the regulation will result in increased demand for accessible content from third-party vendors, and therefore an increase in the number of third-party vendors equipped to provide accessible digital textbooks.

Nearly every piece of digital material hosted by a local government will need to be compliant, including web content that is password protected. Some exceptions include archived web content for recordkeeping or reference that has not been updated since the entity’s compliance date kicked in, pre-existing social media posts, and content posted to a government site or mobile app by third parties, unless those contributors have a contract, license or arrangement to post to government websites.

Given the scope of potential web accessibility improvements, the deadlines may be tough to meet for school districts and universities that have lots of digital content not already accessible under the WCAG standard, according to Rice of the University of New Mexico.

“This is going to throw a real wrench into Teachers Pay Teachers and other stuff like that,” Rice said, referring to the online marketplace for instructional resources.

Teachers Pay Teachers, when asked to respond, declined to comment.

Rice recommends that school districts be leery of vendors that promise to quickly make their web content compliant. “Schools should keep their eyes peeled and their pocketbooks guarded,” Rice said. “I can almost always promise you that anybody who says that they can do it fast and quick is a liar.”