The multidisciplinary INTO project is developing testing and training for respiratory protective equipment to improve protection

The role of airborne transmission in the spread of respiratory infections has become more evident in recent years. Particularly in the social and healthcare settings, there are situations where the risk of infection cannot be sufficiently reduced through technical or operational measures; instead, personal protective equipment is a critical component of workplace safety. 

Respiratory protective equipment protects not only against viruses but also against other airborne particulate contaminants.

The focus is on measuring the actual protective effectiveness of respiratory protective equipment during both inhalation and exhalation

Previous research has largely focused on laboratory measurements of respiratory protective equipment and leakage during inhalation. In the INTO project, carried out by Tampere University of Applied Sciences (TAMK), the University of Helsinki, and Tampere University, the focus is expanded to include leakage during exhalation as well as performance in dynamic work situations, that is, how the respirators perform while moving and speaking, and during varied work tasks. 

“This is important because in healthcare, respirators not only protect the user but also nearby patients and coworkers,” explains Project Manager and Principal Lecturer Sampo Saari from Tampere University of Applied Sciences. 

In Finland, ensuring the proper fit of respirators has been inconsistent in many workplaces, and no widely adopted, practical methods have become established in daily practice. Saari considers this a significant shortcoming: 

The specifications of respiratory protective equipment do not always guarantee actual protection. True protection is achieved only when the respirator fits properly and is used correctly.”

Sampo Saari

Measurements are taken in the laboratory and in real-life work environments

The study examines, among other aspects, the effect of the fit of respiratory protective equipment, inflow and outflow across different particle sizes, and various usage scenarios in which the respirator may behave differently than in a standardized test.

In testing, the researchers use both human test subjects and standardised 3D-printed model heads to assess how well the new size classifications in accordance with ISO standards help in selecting a respirator of the appropriate size. 

“We are also developing new measurement methods to reliably and reproducibly quantify leakage in respirators and to assess the suitability of pressure differential measurement for rapid workplace fit testing,” says Postdoctoral Researcher Lotta Oksanen from the University of Helsinki.

One of the research questions concerns the carbon dioxide concentration inside the respirator, for which the existing data is inconsistent. The aim is to produce accurate measurement data that can be applied to both occupational safety and well-being at work. 

“When we simultaneously measure respirator leaks, the effect of particle size on protection efficiency, and the conditions inside the respirator, we obtain a comprehensive picture of the respirator’s performance,” explains Professor Topi Rönkkö from Tampere University. 

The goal: protection based on measured data

The goal of the project, funded by the Finnish Institute of Occupational Health, is to shift the use of protective equipment from assumptions-based practices and routines toward data-driven and standardized approach.

When the fit, leaks, and usage of respiratory protective equipment can be reliably assessed, workers are able to select the appropriate equipment and ensure an effective seal even in real-life situations. This can reduce occupational exposure to infections and, consequently, decrease related sick leave while improving patient safety.

“In addition to scientific results, we will produce guidelines and training materials for workplaces to help integrate protective practices into daily routines. The plan is to distribute these to target groups via the project’s website and through stakeholder networks,” Saari says.

INTO is a multidisciplinary project that combines perspectives from aerosol physics, medicine, and workplace research. Practical collaboration is carried out with social and health care providers, occupational safety experts, and companies to ensure that the developed methods serve real-life needs as effectively as possible