The Department of Veterans Affairs (VA) is issuing this interim final rule to amend its adjudication regulations to establish presumptive service connection for three chronic respiratory health conditions, i.e., asthma, rhinitis, and sinusitis, to include rhinosinusitis, in association with presumed exposures to fine, particulate matter. These presumptions would apply to veterans with a qualifying period of service, i.e., who served on active military, naval, or air service in the Southwest Asia theater of operations during the Persian Gulf War (hereafter Gulf War), as well as in Afghanistan, Syria, Djibouti, or Uzbekistan, on or after September 19, 2001, during the Gulf War. This amendment is necessary to provide expeditious health care, services, and benefits to Gulf War Veterans who were potentially exposed to fine, particulate matter associated with deployment to the Southwest Asia theater of operations, as well as Afghanistan, Syria, Djibouti, and Uzbekistan. The intended effect of this amendment is to address the needs and concerns of Gulf War Veterans and service members who have served and continue to serve in these locations as military operations in the Southwest Asia theater of operations have been ongoing from August 1990 until the present time. Neither Congress nor the President has established an end date for the Gulf War. Therefore, to provide immediate health care, services, and benefits to current and future Gulf War Veterans who may be affected by particulate matter due to their military service, VA intends to provide presumptive service connection for the chronic disabilities of asthma, rhinitis, and sinusitis, to include rhinosinusitis, as well as a presumption of exposure to fine, particulate matter. This will ease the evidentiary burden of Gulf War Veterans who file claims with VA for these three conditions, which are among the most commonly claimed respiratory conditions.