Barriers to Suicide Act of 20 21 This bill requires the Department of Transportation (DOT) to establish a program to facilitate the installation of evidence-based suicide deterrents on bridges, including suicide prevention nets and barriers. DOT may award competitive grants to states and local governments to carry out the program. The Government Accountability Office must conduct a study to identify the types of structures, other than bridges, that attract a high number of individuals attempting suicide-by-jumping and the types of nets or barriers that are effective at reducing such suicides.