On October 16, 2001, President George W. Bush signed legislation asking that the American flag to be lowered to half-staff on all Federal buildings to honor fallen firefighters.
The resulting Public Law 107-51 involves this action to occur every year in conjunction with observance of the National Fallen Firefighters Memorial Service weekend which is October 5-6, 2019.
To be clear, the actual flag-lowering should be done on the last day, which is the 6th. This doesn’t mean that it only applies to Federal buildings, everyone is encouraged to join in this observance. Individual state Governors will most likely make their own proclamations and so will the President of the United States of America.
119 firefighters lost their lives since last year’s memorial. This is sadly one of the most overlooked half-staff memorials, probably due to being held on a Sunday.