Originally, OR attire was white to emphasize cleanliness. However, the combination of bright operating lights and an all-white environment led to eyestrain for the surgeon and staff. By the 1950s and 1960s, most hospitals had abandoned white OR apparel in favor of various shades of green, which provided a high-contrast environment, reduced eye fatigue, and made bright red blood splashes less conspicuous.
Green Scrubs being worn by operating staff in an ORBy the 1970s, surgical attire had largely reached its modern state: a short-sleeve V-necked shirt and drawstring pants or a short-sleeve calf-length dress, made of green cotton or cotton/polyester blend. Over this was worn a tie-back or bouffant-style cloth cap, a gauze or synthetic textile mask, a cloth or synthetic surgical gown, latex gloves and supportive closed-toe shoes. This uniform was originally known as "surgical greens" because of its color, but came to be called "scrubs" because it was worn in a "scrubbed" environment.
 Modern scrubs
Today, any medical uniform consisting of a short-sleeve shirt and pants are known as "scrubs". Scrubs may also include a waist-length long-sleeved jacket with no lapels and stockinette cuffs, known as a "warm-up jacket". Nearly all patient care personnel in Canada and the United States wear some form of scrubs while on duty, as do some staffers in doctor and dental offices. Support staff such as custodians and unit clerks also wear scrubs in some facilities.