NEW BEDFORD — When it comes to the N95 personal protective masks at Southcoast Health System, one size definitely doesn't fit all.
Southcoast Health System employs a procedure called the Fit Test, a requirement of all hospitals by the U.S. Department of Occupational Safety and Health, to make sure the N95 personal protective mask is sealed to the caregiver's face and does not interfere with the employee's movements when working, according to Southcoast Health System officials and OSHA's website. While an OSHA requirement, it was not implemented because of COVID-19.
The involved procedure is done for the protection of employees, especially when treating COVID-19 patients, and takes about 15 minutes each worker.
"We take the process seriously. It's very important," said Phil Oliveira, vice president of support services for Southcoast Health System. "We do it to protect our team and find the correct personal protective equipment to treat the patient."
"This is not like trying on shoes," he said.
Since no one person has the same facial features, the first step in the Fit Test is to find "the right mask" from an assortment of different makes, models and manufacturers for the worker, one that is compatible with their facial characteristics, he said.
An instructor teaches the worker the correct way to put on the mask, which is called donning, and remove it — referred to as doffing, according to Oliveira and OSHA website.
OSHA has released guidance on its website about the Fit Test because of supply shortages of N95 filtering face piece respirators due to the COVID-19 outbreak.
The instructor observes the worker as they adjust the mask and asks them if there is room for eye protection and to speak, while wearing the N95 mask, he said. "It's pretty important to make sure it fits," he said.
The employee is asked to perform "exercises" to see how the mask fits on their face and how the employee functions wearing it, he said. They are asked to move their head from side to side and up and down as the instructor observes.
The instructor watches as the worker performs these exercises and asks the employee how it feels on their face, he said.
Next comes the crucial two-step process involving distilled water and about a milliliter of Bitrex, the brand name for a substance called "the bitterest substance in the world," according to Bitrex's website.
"Bitrex is very, very bitter. In fact The Guinness World Records lists Bitrex as ‘the most bitter substance in the world,’ the company said on its website.
"Drop a thimble-full of Bitrex into an Olympic swimming pool and you can detect the bitterness in those two and a half million litres of water," the website said. "But despite this bitterness, Bitrex is itself harmless. It won’t make you sick or ill, it just tastes so bitter that you will want to spit it out – fast."
Bitrex is used in accidental poisoning, especially with children, the company's website said.
Two tests are performed on the worker — one involving a medical hood without the N95 mask and the other with the worker wearing both the hood and the mask, he said.
The solution of Bitrex and distilled water is squeezed 10 times in a series of three applications into the nebulizer on the mask, and the worker is asked, "Can you taste it," Oliveira said. The purpose of this test is to find the worker's "baseline," he said.
Then the test is repeated the exact same way while the worker wears an N95 mask under the hood, he said. The idea is to make sure the mask is sealed to the contours of the worker's face.
"At any time you taste the Bitrex, the mask failed," he said. "That mask doesn't work."
If the worker doesn't taste the Bitrex solution, then that model and make of the mask is the worker's personal mask and the information about it is recorded into the hospital's computer system when they need another one. "Then we know that mask fits properly," he said.