Sight and sound are crucial elements in the success of distance learning classrooms. However, there is much more to consider than just the types of audio and video equipment to be used. Proper classroom acoustics, good speech intelligibility, clear sightlines, proper lighting, and seating arrangements all need to be considered when developing an effective distance learning classroom that will benefit students and instructors alike. Considerations when choosing a room to renovate into a distance learning room include:
- Quiet, well-isolated space with low reverberation time
- Few or no windows
- Controllable lighting, preferably designed for distance learning
- High volume, low velocity HVAC systems
- Gasketed doors or vestibules
- Fixed desks or tables and tiered seating
- Unobstructed sightlines and camera angles
- Appropriate finishes
Let’s discuss these components and look at how best to accommodate each one within a distance learning environment.
Can you hear the other person? Can they hear you?
The best microphones on the market may be installed in a classroom, but without proper acoustics, these microphones will not cure speech intelligibility problems. Studies have shown that classrooms with speech intelligibility problems and poor acoustics that cause noise disturbance can lead to lower test scores. Distance learning classrooms, both the near-end room and the far-end room, can suffer from the same problems. What acoustic issues need to be considered when planning a distance learning space?
Reverberation (echoed sound) is the enemy of understanding speech clearly. To control reverberation, adequate absorption must be installed in the classroom to alleviate sound from reflecting off multiple surfaces and leading to a buildup of reverberant energy. Acoustic ceiling tiles, fabric-wrapped fiberglass wall panels, fabric drapes, and carpet are commonly used in classroom renovations to control reverberation and improve room acoustics.
Building systems, such as HVAC, fluorescent lights, fans, air valves, and diffusers, can also cause background noise problems that make speech audibly difficult, especially if sensitive microphones transmit the noise to the distant learning space. When creating a distance learning classroom within an existing facility, curing noise from building systems can be one of the most difficult acoustic problems to solve. Careful consideration must be given to upgrading to quieter systems to provide a more acoustically comfortable classroom.
Distance learning classrooms must also have adequate sound isolation to keep exterior noises from the corridor or the street from intruding into the classroom. It is ideal to choose a classroom that is away from bathrooms, elevators, HVAC compressors, and other noise producing motors and/or plumbing. If this is not possible, rooms should be built-out with walls, floors, and ceilings that can effectively reduce or block the intruding noise. Door gaskets and acoustically rated windows can cut down on the amount of noise “leaking” into the classroom from these sources.
Can we all see each other?
One of the often-overlooked aspects of distance learning is good eye contact. Like any other type of conversation, people are more comfortable when they can clearly see the other person’s face. Two primary considerations, the interactivity of the distance learning session and who needs to see whom, will drive design decisions such as camera layout, seating layout and lighting design.
If only the instructor needs to be seen, the camera and seating layouts become simplified. Depending on classroom size, flexible seating on a flat floor and a single camera location can be sufficient. In larger classrooms and in instances where the instructor and students need to be seen at the distance learning site, permanent tiered seating and two or more camera locations will need to be considered.
To promote good viewing, room lighting should be designed to be both people and camera-friendly. The correct types and proper placement of lighting fixtures should be used to reduce glare and veiling reflections on projected images. Specific distance learning and video conferencing lighting equipment has been developed to help alleviate these issues. The selection of materials and finishes for wall panels, ceilings, and furniture must also be video-friendly to avoid moiré effect and reflective glare, and the reflectance values of finishes and colors should be considered. For faces to be clearly seen, it is important to have a good contrast ratio between the flesh tones of the face and the surrounding surfaces so that participants do not blend into the background.
Additionally, lighting should come from an angle between 45° and 60° vertical. Horizontally, light should also be cast on the face from an angle in addition to front. This will assure that minimum shadows are created in the eye sockets and under the nose and chin. Direct overhead lighting will cast shadows on the eyes and mouth, making it difficult to decipher lip movement.
Room Planning for Distance Learning
Typically, schools choose to use an existing facility rather than build a new one for distance learning purposes. In this case, there are some potential expenses that could drive the price of retrofitting a room above the projected costs. Some issues to consider when determining project costs for repurposing an existing room for distance learning include:
- Low background noise (Noise Criterion 25 or NC25) often requires low velocity, high capacity HVAC design
- Isolation from external noise may require specialized wall constructions, window and door gasketing
- Reverberation requirements of less than one second will require special wall and ceiling treatments
- Exterior windows are problematic for light control
- Specialized videoconferencing lighting may require custom ceiling design
- Tiered seating may be required in larger venues for proper viewing, as flat seating may not work
Keep in mind that not all rooms are ideal for distance learning and the costs to retrofit may exceed the costs of building a new space. Physical constraints that can make an existing room unsuitable for distance learning include: a ceiling too low for the planned group size, impairing camera angles and audience visibility; HVAC noise that is too loud, causing poor speech intelligibility and microphone audibility; inappropriate lighting that creates shadows; and a room layout or ADA requirements that do not allow for tiered seating, creating poor sightlines for students.
Technology for distance learning evolves quickly, but the room requirements have remained generally the same. Though it is important to stay abreast of the latest technology when developing a distance learning classroom, it is equally important to carefully plan the space as well. Even the latest and best technologies cannot overcome physical problems inherent in a room.
Linda Gedemer, LEED AP, CTS, Assoc. AIA, is a senior consultant at Acentech Inc.