The federal flag code says the universal custom is to display the U.S. flag from sunrise to sunset on buildings and stationary flagstaffs in the open, but when a patriotic effect is desired the flag may be displayed 24-hours a day if properly illuminated during the hours of darkness. Also, the U.S. flag should not be displayed when the weather is inclement, except when an all-weather flag is displayed.
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DISPLAYING THE FLAG
On Same Staff:
U.S. flag at peak, above any other flag.
Grouped:
U.S. flag goes to its own right. Flags of other nations are flown at same height.
Marching:
U.S. flag to marchers right (observer’s left).
On Speaker’s Platform:
When displayed with a speaker’s platform, it must be above and behind the speaker. If mounted on a staff it is on the speaker’s right.
Decoration:
Never use the flag for decoration. Use bunting with the blue on top, then white, then red.
Salute:
All persons present in uniform should render the military salute. Members of the armed forces and veterans who are present but not in uniform may render the military salute. All other persons present should face the flag and stand at attention with their right hand over the heart, or if applicable, remove their headdress with their right hand and hold it at the left shoulder, the hand being over the heart.
Over a Street Union:
(stars) face north or east depending on the direction of the street.
Half Staff:
On special days, the flag may be flown at half-staff. On Memorial Day it is flown at half-staff until noon and then raised.