A bill banning the racial discrimination of natural hair in the workplace and schools has been passed in California.

Senate Bill 188, otherwise known as the "Create a Respectful and Open Workplace for Natural Hair" Act (the Crown Act) was passed unanimously, by a vote of 37 to zero, in the western American state's Senate.

Introduced by Senator Holly J Mitchell, the aim of the bill is to dispel misconceptions about black hair, while also challenging "common-held myths about what constitutes professionalism in the workplace".

Senator Mitchell explained how black employees and students frequently faced discrimination due to the natural texture of their hair.

"Until very recently, a Google image search for, quote, 'unprofessional hairstyles', yielded only pictures of black women with their natural hair, or wearing braids or twists. Although disheartening, this fact was not surprising," the senator said.

Senator Mitchell said that for decades, many black men and women did not challenge the societal standards which dictated how they should style their hair, often having "no choice but to conform to harsh and expensive standards", such as straightening their hair with chemical relaxers.

The politician said that on many occasions, black employees or applicants for jobs have been denied employment, promotions or have even lost their jobs due to their natural hair.

The senator detailed how supposed "neutral policies" in the workplace, which ban hairstyles such as braids, cornrows and dreadlocks for people of all races, have a "desperate impact" on the black community.

"These policies are far more likely to exclude black people from the workplace than people of any race," she said.

Senator Mitchell also spoke about the "humiliation" numerous black children faced when they were sent home from school on the basis their natural hair was "unruly" and a "distraction" to other children.

“Any law that sanctions a job description that immediately excludes me from a position, not because of my capabilities or experience but because of my hair, is long overdue for reform," the senator said as she closed her speech on the Senate floor.

The bill is sponsored by a coalition between the National Urban League, the Western Centre on Law and Poverty, civil rights organisation Colour of Change and cosmetics company Dove.