Alert status one

From Memory Alpha, the free Star Trek reference

Alert status one was a Klingon alert signal.

In 2373, first officer Worf issued an alert status one on board the IKS Rotarran after detecting a Jem'Hadar patrol ship running active polaron scans of a sector outside of the Cardassian border. (DS9: "Soldiers of the Empire")

In 2374, whilst performing convoy escort duty, the Rotorran was again put on alert status one after a Jem'Hadar fighter was detected. After several minutes, it turned out that it was just a battle simulation that Alexander Rozhenko had forgotten to switch off. General Martok then stood the ship down from the alert. A short time later, the ship was put on alert when a group of three Jem'Hadar fighters attacked the convoy. The Rotarran was damaged but successfully managed to destroy them. (DS9: "Sons and Daughters")

Along with the alert, the crew were ordered to prepare for combat operations, indicating that alert status one may be the equivalent of a red alert aboard Starfleet vessels.