Protection Effectiveness of a Building-Integrated COVID-19 Sampling Station That Uses a Sealed Acrylic Window as a Physical Barrier.

To the Editor:

Because a healthy and efficient medical workforce is key to containing the present coronavirus disease 2019 pandemic, the protection of health care workers is paramount. , According to the interim guidance for the pandemic from the World Health Organization, health care workers must don personal protective equipment (PPE) when testing a patient with a high suspicion of having pneumonia. Such PPE must include an N95 respirator, a pair of goggles or a face shield, a gown, and a pair of gloves.

However, this set of PPE cannot cover all surfaces of the body. Thus, to minimize the risk of exposure to the pathogen, and to conserve PPE, we constructed a building-integrated sampling station. Designed by Tseng Yu-Chi and Tseng Kai-Chen, this station has a sealed acrylic window serving as a physical barrier separating the interior (where the physician is) from the exterior (where the patient is), and a pair of sealed rubber gloves affixed to the station for the physician to perform nasopharyngeal sampling. The exterior (patient side) is thoroughly disinfected before another patient receives sampling.

We conducted a simulation in the emergency department of Taichung Tzu Chi Hospital in Taichung, Taiwan, on April 20, 2020, to test whether this device can fully protect the physician. A physician was equipped with the full set of World Health Organization–recommended PPE—a fluid-resistant gown, N95 respirator, pair of gloves, pair of goggles, and hair cap—and then collected a nasopharyngeal swab sample from a patient face to face (Figure , B). The patient held a sprayer filled with fluorescent agent and sprayed it toward the physician, mimicking the droplets or aerosols produced by a real patient. We then checked where the fluorescent agent landed by using a black light. When the station was not used, we found that the fluorescent agent passed through the face shield and settled on the skin of the physician’s neck (Figure, D). However, when the station was used, no fluorescent agent was found on the surface of the physician’s body (Figure, C). When using our station, the physician was not wearing any PPE and was separated from the patient by the acrylic window. The physician took samples from the patient by using the fixed and sealed rubber gloves (Figure, A). In contrast to the absence of fluorescent agent on the physician’s body, there was a broad distribution of fluorescent agent on the exterior, such as on the window, desk, and even roof of the station.

Figure

Simulation comparing the protectiveness of the standardized PPE and designed building-integrated sampling station. A, The physician, located behind the acrylic window and without PPE, taking samples from the patient on the other side of the window, using the fixed and sealed rubber gloves. B, The physician, equipped with standard World Health Organization–recommended PPE, taking samples from the patient by using a nasopharyngeal swab face to face at a short distance. C, The acrylic window of the sampling station resulted in no fluorescent agent on the surface of the physician’s body. D, When only PPE was used, the fluorescent agent still passed through the face shield and settled on the skin of the physician’s neck.

On the basis of the results of our experiment, we recommend our specially designed, building-integrated sampling station to health care workers who sample face to face at a short distance for patients with suspected respiratory infection. Our station conserves PPE and protects health care workers from viral infection. If our station is not available, health care workers should use PPE (preferably with full-body coverage) and thoroughly clean it after taking it off.