A new study tested over 30 different do-it-yourself materials, including bra pads, coffee filters, pillow cases, cotton t-shirts, bed sheets and several others.
The study tested the effectiveness and breathability of each material.
Scarves and bandanas actually made the bottom of the the list.
The top five were denim, bed sheets, paper towels, canvas and shop towels.
Face coverings are required at businesses throughout Los Angeles County. The ordinance, passed by the Los Angeles County Board of Supervisors, makes face coverings mandatory for workers at grocery stores, pharmacies, food delivery platforms and other essential businesses.
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Under the new guidelines, businesses must either provide employees with non-medical grade cloth face coverings, gloves and hand sanitizer or give workers money to buy these items. Employees, in turn, must wear face coverings and gloves while at work.
Shoppers must also put on a facial covering, including scarves and bandanas, while in an essential business. The measure allows grocery and drug stores to refuse service to any customer not wearing a face mask. Those who do not comply to the mandate risk being fined.
Orange County supervisors passed a mandate on Tuesday requiring face coverings for workers in grocery stores and food preparation businesses, a week after passing a resolution strongly recommending them.
The mandate requires that all employees who may have contact with the public in any grocery store, pharmacies, convenience stores, gas stations, restaurants, food preparation and retail stores wear facial coverings at work.
The requirement goes into effect at midnight on Friday.
In Riverside County, health officials ordered residents to stay home and cover their faces when leaving.
How to make a face mask without sewing