By the mid-1950s, the Canadian army began to move away from its drab, utilitarian, wartime look. An important part of this official movement was to introduce the Blue Patrol uniform.
Blue patrol dress was approved for all Officers, Warrant Officers and NCOs above the rank of Lance Sergeant. (A corporal could be appointed lance-sergeant to hold the employment of a Sergeant.) Patrol dress consisted of a dark blue jacket, a closed collar, and matching trousers.
The red sash is worn by many members of the British army but was originally worn by an Infantry soldier in battle who was in charge of holding the regimental colours together with a junior officer (ensign). The soldiers acted as a rallying point in the confusion of battle.
It is an old tradition in the British and Empire/Commonwealth military that both officers and sergeants wear a red sash. The purpose was twofold: it made the officers and sergeants distinctive in the fog of war, but also acted as a litter for wounded and (in the case of officers) as a shroud (a cloth used for wrapping a dead body). By 1881 a change was moving the sash from and to shoulder and waist during various periods.
The forage cap/hat worn with Patrol Dress by other ranks was similar to the officers but was of a lesser quality and worn with a brass cap badge. This hat was also worn as a service dress hat with battledress and bush orders of dress.
Officer Forage cap, 1957
RCASC Cap Badge