White coat
A white coat or laboratory coat (abbreviated lab coat) is a knee-length overcoat/smock worn by professionals in the medical field or by those involved in laboratory work to protect their street clothes. The garment is made from white cotton or linen to allow it to be washed at high temperature and make it easy to see if it is clean. Similar coats are a symbol of learning in Argentina, where they are worn by students.
When used in the laboratory, they protect against accidental spills, e.g. acids. In this case they have to have long sleeves and be made of an absorbent material, such as cotton, so that the user can be protected from the chemical. Some lab coats have buttons at the end of the sleeves, to secure them around the wrist so that they do not hang into beakers of chemicals.
Like the word "suit", the phrase, "white coat", is sometimes used to denote the wearer, i.e. the scientific personnel in a biotechnology or chemical company.

# White coats in medicine
White coats are sometimes seen as the distinctive dress of physicians, who have worn them for over 100 years.  Recently, white coat ceremonies have become popular amongst those starting medical school.
The white coat was introduced to medicine in Canada by Dr. George Armstrong (1855-1933) who was a surgeon at the Montreal General Hospital and President of the Canadian Medical Association.
Some doctors in institutions such as the Mayo Clinic are instructed to wear business attire, to convey professionalism, as the clinic dislikes the message that white coats represent to the patient.

## Patient preference
A systematic review found "patients often prefer formal physician attire, perceptions of attire are influenced by age, locale, setting and context of care".
A subsequent study found similar results (see chart and photos).
An earlier study found that the majority of patients prefer their doctors to wear white coats, but the majority of doctors prefer other clothing, such as scrubs The study found that psychiatrists were among the least likely to wear white coats, perhaps in part due to the stereotyping that the pop culture phrase suggests. Some medical doctors view the coats as hot and uncomfortable, and many feel that they spread infection.
Ties may have higher bacterial counts. However, the clinical consequences are uncertain.
Other studies of physician appearance suggest that physicians should display open posture.

## White coat hypertension
Some patients who have their blood pressure measured in a clinical setting have higher readings than they do when measured in a home setting. This is sometimes called "white coat hypertension", in reference to the traditional white coats worn in a clinical setting, though the coats themselves may have nothing to do with the elevated readings.

## In psychiatry
The term is also used as verbal shorthand for psychiatric orderlies or other personnel and may be used, in a usually jocular manner, to imply someone's lunacy. In the 1966 song, They're Coming to Take Me Away Ha-Haaa!, Napoleon XIV fictionalized the public's view of the symbolic relationship between such institutions and white coats in the following lyrics:
They're coming to take me away ho ho hee hee ha haaa!
To the funny farm,
Where life is beautiful all the time.
And I'll be happy to see those nice young men
In their clean white coats,
And they're coming to take me away ha haaa!

## White versus black
Until the mid 1920's, students who were examining cadavers would wear black lab coats to show respect for the dead.  Black lab coats were used in early biomedical and microbiology laboratories because any dust (i.e. contamination) that settled on them was easily visible.

## White coat ceremony
A white coat ceremony (WCC) is a relatively new ritual that marks one's entrance into medical school and, more recently, into a number of related health-related schools and professions. It originated in Columbia University's College of Physicians and Surgeons in 1993 and involves a formal "robing" or "cloaking" in white lab coats.

# Biology
In industries and institutions related to biology, white and green coats are used. Typically, white coats are used in laboratory work.

# Argentina
In Argentina white coats which resemble lab coats are worn by students and teachers of most public primary schools as a daily uniform.