Every ordinance except an emergency ordinance shall go into effect thirty (30) days after its final passage unless it specifies a later date. An emergency measure necessary for the immediate preservation of peace, health, or safety shall go into effect upon its final passage unless it specifies a later date. Such an emergency measure must state in a separate section the reasons why it is necessary that the measure become effective immediately. The question of emergency must be ruled upon separately and approved by the affirmative vote of at least three-fourths (3/4) of all the members of the governing body of the municipality.
Okla. Stat. tit. 11, § 14-103