Good lighting makes a big difference in the quality of indoor veterinary environments, especially in exam areas. In equine veterinary spaces, proper lighting can also positively affect horses’ behavior, making for more successful examinations and treatments.
The Sun Is the Best Lightbulb
Before we discuss the methodologies for good artificial lighting, don’t forget that lighting design should start with natural daylight whenever possible. In human healthcare settings, natural lighting is linked to shorter patient recovery times. Animals are physiologically similar enough to people to benefit from the same supportive properties of natural lighting.
While health benefits are only potentially relevant for inpatient care, using natural daylight first, before artificial lighting, can help equine veterinarians save money. Sunlight provides approximately 140 lumens of light for each watt of heat energy produced (per EnergyStar.gov), making it the most efficient lighting system available. By utilizing properly located natural daylight, a hospital can benefit from significantly lower utility costs.
To use natural daylight properly, orient your treatment and barn spaces to take advantage of southern and northern exposures, as eastern and western exposures can bring in too much heat in most climates. For example, a treatment room lit with a long band of northern light high on the wall will feel ethereal and evenly lit, and it will need fewer artificial lights. When employing southern exposures, use roof overhangs to keep out the hot, high, summer sun, while letting in the low, warm, winter sun. An architect or designer can help you achieve the best results.
Match Nature with Artificial Light
Equine hospitals are by nature indoor/ outdoor spaces. Examinations and work-ups might occur inside or outside, depending on the task and the weather. Ideally, the indoor spaces should be lit to feel as natural as possible in order to diminish the contrast between the indoor and outdoor space. LED lighting is the way to go for both energy savings and a natural feel indoors. LED lighting is superior to fluorescent lighting because it:
- naturally mimics the spectral distribution of sunlight;
- eliminates the buzz and flicker you may associate with older light fixtures; and
- comes in a broad range of “color temperatures.”
Color temperatures are expressed in degrees Kelvin. The higher the number, the colder or bluer the light. Direct sunlight is around 4,800K. Select bulbs that are in the 4,000K range to strike a good balance between mimicking natural sunlight and eliminating an overly cold feeling indoors. 4,000K bulbs emit a white, crisp light, and this is also best for making veterinary spaces feel clean, bright and sanitary.
Illuminate for the Task
The next principal of proper lighting is to consider the task and light appropriately for it. While this might seem elementary, many veterinarians do not have access to information about how much illumination is needed based on task.
Below are rules of thumb for illumination, expressed in the illuminance measure “foot-candles.” For reference for the standards below, 30 foot-candles is a typical office building space illumination level.
- 20 foot-candles is the minimum for storage spaces and barn aisles.
- 30 foot-candles is the minimum for utility spaces where tasks are performed (laundry, feed rooms, etc.), as well as for equine outpatient stalls and offices.
- 45 foot-candles should be used for lab and pharmacy spaces, where more detailed tasks are performed.
- 50 foot-candles is the minimum for equine exam and treatment spaces and medical stalls.
- 75 to 100 foot-candles is the minimum for surgery rooms.
Your electrical engineer or lighting designer should be able to design to the above standards, and it is critical that he or she does so to ensure that your facility works as well as you want it to.
In addition to general illumination levels, consider the following when designing the lighting in an equine veterinary space:
- Light the area you want to see into more brightly than the area around it. For example, medical observation stalls should always be more brightly lit than the stall aisles in front of them, so doctors and technicians can readily see the patients.
- Provide secondary task lighting at work surfaces. For example, pendant lights over the reception desk will help light the transaction counter where clients are filling out forms.
- Provide cross lighting for all equine stocks and other stationary exam areas. Install light fixtures on both sides of the equine stocks rather than right over them. This will help you achieve even, glare-free illumination.
- Provide dimmable lighting. LED lights are easy to dim, and this is a great feature to incorporate when you need to turn the lighting down when daylight levels are high, for example, or to keep patients quiet in their stalls.
Avoid Shadows
Horses are prey animals, and they constantly watch for danger. While horses can see about 350 degrees around their bodies, they lack much binocular vision, and they have trouble with depth perception. For these reasons, they are afraid of dark corners, shadows and other areas that are hard to comprehend visually.
We want to eliminate fear in veterinary spaces, so equine veterinary treatment areas should be lit evenly, brightly and without shadows. Use these techniques:
- Space the light fixtures evenly for even illuminance in all areas of the room, especially corners and room edges.
- Avoid blocking light fixtures with furniture or equipment.
- Light connecting spaces evenly to avoid shadowy, foreboding vistas.
- Avoid conflicts between ceiling fans and light fixtures. If ceiling fans are hung under light fixtures, they will cause a “strobe” effect, which is the opposite effect from what we would hope to achieve in a space intended to keep horses calm. Space the lights far from the ceiling fans, or hang them below the fans.
Choose the Right Fixtures
In equine areas, it is important to choose practical lighting fixtures. Equine veterinary areas are generally dusty and sometimes damp, and must be safe.
Choose light fixtures with sealed, damp-rated covers for safety and ease of cleaning.
Do not choose anything that is shaped like a basket or bowl, or it will collect every dead moth in the county in the first two weeks after installation, and that will cause a constant cleaning hassle for you.
In areas where large equipment could bump a light fixture (such as in barn aisles), choose fixtures with safety cages over them.
Reduce the number of bulbs you will need to stock by choosing fixtures with identical bulb types, when possible. This is not as important with LED lighting as it is with fluorescent fixtures, because LED bulbs are replaced infrequently. Still, standardizing your bulbs will make your life easier.
Go the Extra Mile
In the design world, we are starting to better understand the relationships between lighting and physical and psychological well-being. Picture a police interrogation room; it is often depicted in movies as having a single, yellow lightbulb hanging from above a table. This space is lit that way to make the person being interrogated feel uncomfortable.
Many horse owners already know something about lighting’s relationship to a horse’s physiology. Show barns use extended artificial lighting to prevent the horses’ winter coats from growing. In equine veterinary settings, we can embrace this way of thinking about the power of lighting in a way that is focused on equine health and wellbeing.
The more we recognize the way a horse sees, the more we can provide lighting that promotes the comfort of horses. For example, night emergency lighting typically utilizes blue light. But blue light is not desirable as night lighting in equine medical barns, because horses see very well in the blue end of the spectrum, and they have a hard time resting under constant blue light.
Use red emergency lighting instead, and this problem is eliminated, as horses do not see the red end of the spectrum. A medical barn lit at night with low levels of red light would be restful and dark as perceived by the horses.
While there are likely many undiscovered relationships between lighting and wellbeing, we offer these additional thoughts:
- Replace any fixture that noticeably flickers, as horses perceive the flickering of the fixture more clearly than we do.
- Use LED lights when possible. As described in this article, LED lighting is superior, but when we consider a horse’s perspective, it is the best lighting to use. LED lights produce an even spectral distribution, heavy on the bluer end of the spectrum. Horses do not see red and orange frequencies, so LED lighting is essentially tuned to their visual acuity, which helps them see and perceive spaces better.
- Use high levels of even illumination in arenas and work-up areas. Because horses do not perceive depth well, a poorly lit work-up area can be visually distracting for the horse, which can lead to a less successful lameness exam.
Take-Home Message
Veterinarians should consider what horses see, how they think and what elements help to create good spaces for working with them. Whether you plan to build a new facility or simply upgrade your current lighting fixtures, apply your knowledge of horses to create well-lit, low-stress spaces.
