Icons can be a great way to convey meaning across smaller viewports. If your using icon fonts for social icons, three lines for menus, magnifying glass for search etc then you should understand the possible issues and solutions that come along with their use.
Care must be taken when implementing icon fonts to ensure a great experience for all users. What happens when your font doesn’t load? What happens when @font-face isn’t supported in the browser? We’ll show you how to implement bulletproof font icons.An excerpt from Bulletproof Accessible Icon Fonts