Block the Virus, Not the Learning
In the Centers for Disease Control and Prevention’s Considerations for Schools: Operating Schools During COVID-19, the CDC recommends the installation of “physical barriers, such as sneeze guards and partitions, particularly in areas where it is difficult for individuals to remain at least 6 feet apart.” OSHA’s Guidance on Preparing Workplaces for COVID-19 publication also suggests, “installing physical barriers, such as clear plastic sneeze guards,” as a defense against the spread of COVID-19. In general, sneeze shields are recommended wherever it is not possible for people to remain more than six feet away from others, or when they simply forget to do so.
Sneeze shields have been widely used in school cafeterias for decades. However, their use in our “new normal” of American education is different. Rather than preventing students from dipping their fingers into the mashed potatoes, sneeze shields today are installed to create peace-of-mind for administration members, students and teachers during all face-to-face interactions where the shields serve as a way to:
• Intercept COVID-19 respiratory droplets;
• Re-enforce physical distancing requirements;
• And compliment the use of masks.
Ultimately the goal of sneeze guards in schools is to block the virus, not the learning.
Sizing up Safety
To ensure that a sneeze shield performs its assigned duties, the most critical factor is that its dimensions exceed the users’ breathing zones by a wide margin. What is a breathing zone? It is defined as the pocket of air from which a person draws breath. Imagine a bubble with a radius of 12 inches extending from the mid-point between a student’s ears. That “bubble” is the breathing zone.
Sneeze shield height and width are based on an average-sized person who is between five and six feet tall. In the United States the average height for men is five feet, 9 inches tall, while for women it is five feet, 4 inches tall. Obviously, in classrooms for lower grades you should take into account the smaller frames of younger students.
Also, the shield’s height should reflect whether or not people are sitting or standing. For example, in an office area, a student might be standing while an administrator remains in a chair. In this case, the sneeze shields should be the height of the average standing person.
Besides protection of the breathing zone, the width of a sneeze shield should take into account for user behavior, in particular if a student moves to the side of the shield to speak directly to another student. Currently, industry best practice is to make the sneeze shields as wide as the surface it is installed on to prevent circumventing it. Shield designs also may include wings or side panels to provide both stability and further shelter the user’s breathing zone from the potentially harmful emissions from coughing, sneezing, loud talking, laughing, and more.
Because the purpose of sneeze shields is to ensure that a user’s breathing zone is not contaminated, speaking ports or grates should not be installed through the partition. However, sneeze shields often need openings at the bottom to allow for the transfer of items or payment for transactions. These slots should be kept as small as possible dependent on the activity. Also, the slot should be placed off-center, rather than directly in front of the person. If large packages must be passed, a slider or plastic flap can be installed. Please note that sliders and flaps are high-touch surfaces and will need to be sanitized throughout the day.
An alternative, albeit a poor one, to a slot, slider or flaps is to hang sneeze shields from the ceiling with space for transactions underneath. Although more convenient and visually appealing, hanging a sneeze shield leaves a large gap between the shield and the countertop, allowing air to flow through. Also, if the partition is able to swing, it may fan contaminated air from one person to another. Hanging shields are also difficult to clean. Surface-mounted or freestanding shields are the preferred design for school safety.
Sneeze shields are engineering controls that significantly reduce droplet transmission in schools, and should be purchased with great care. Materials vary greatly.
Polycarbonate, an optically transparent yet virtually unbreakable plastic, is an ideal material for sneeze shields. Polycarbonate is advantageous in schools because it is possesses a unique balance of toughness, dimensional stability, optical clarity, and excellent resistance to scratching. Properties such as scratch and impact resistance should be considered before making a selection for schools, especially in higher grades were vandalism may occur. Polycarbonate is also thin, which allows for easy communication between both sides. This is perfect for schools, because it allows students to clearly see and hear their instructions and interact with other students without having to come into direct contact. Additionally, polycarbonate allows access to natural light and shields out harmful ultraviolet rays.
Acrylic (Plexiglas) shields are less expensive than those fabricated from polycarbonate. In a case of “you get what you pay for,” Acrylic is also easier for students to damage and will require more replacements, more frequently. Both acrylic and polycarbonate are stronger than untempered glass. However, acrylic is only 4x to 8x stronger than glass, while polycarbonate is approximately 250x stronger. When struck by an object polycarbonate bends but doesn’t break. When acrylic is struck it stays stiff but cracks and shatters under impact. This exposes students to another potential hazard in addition to COVID-19: sharp plastic shreds. Yet another issue is acrylic is fire resistance. In several states, including New York, the use of acrylic in schools is prohibited, as it does not meet fire code standards.
Some school districts that have re-opened are championing the portable desk sneeze guard. Equipped with a carrying handle to, portable desk sneeze shields are susceptible to being dropped by students onto hard floors. For that reason a hard, virtually unbreakable material like polycarbonate is required.
A sturdy metal frame may be required in instances where sneeze shields are subjected to heavy impact, vandalism, or are placed outside to act as freestanding partitions. A frame is also necessary in applications that need a bolted solution for high traffic areas or a movable solution to roll from one place to the next on caster wheels.
Sneeze shields intercept respiratory droplets. For that reason they must be treated as contaminated surfaces and should be cleaned regularly according to a set protocol. Shields that are not touched should be cleaned daily, whereas portions of the partition that are touched should be cleaned twice daily, or more frequently if visibly soiled, as with other high-touch surfaces.
School districts around the country are hard at work making and installing sneeze guards throughout their facilities. Sneeze guards are installed in their front offices, around and on student desks, separating library and cafeteria tables, and in entrances where temperature checks are being performed. School buses are using them to provide extra separation between students. When combined with social distancing, face masks, hand washing and sanitizing, sneeze guards for schools have the potential to make a major impact on safety and help everyone breathe a little easier this school year.
For more information, please visit www.germblockshields.com or call 1-800-922-7533.