As mask mandates are being lifted for certain parts of the country’s population, it’s important for healthcare workers to remain vigilant in minimizing exposure risk. Recently researchers tested the efficacy of mask modifications on humans and life-sized human anatomical models using simulated coughs and exhalations. Adding an elastic band over a mask or wearing two masks are successful methods for enhancing mask protection against respiratory aerosols, according to a new study from the National Institute for Occupational Safety and Health (NIOSH).

The study found that medical masks without modifications block out 56% or more aerosols and 42% or more exhaled aerosols. When an elastic band is placed over a mask, the study found that it blocked 95% or more cough aerosols and 99% or more exhaled aerosols. In another modification, researchers found that double masking with a three-ply cloth mask on top of a medical mask blocked 85% or more of cough aerosols and 91% or more exhaled aerosols.

The NIOSH study also revealed that earloop toggles, earloop straps, and knotting and tucking a mask could increase performance but not as well as an elastic band or double masking. When the study subjects crossed the ear loops or placed a bracket under the mask, there was no additional protection.

Not only do these modifications offer protection against COVID, but an elastic band or double masking also has capabilities to “reduce the transmission of other respirable infectious pathogens,” according to the NIOSH researchers.

Read more about the study here.