When marine buyers, vessel owners, and procurement managers look at the performance figures for SOLASOLV® anti-glare screens, two numbers stand out: up to 93% glare reduction and up to 87% heat rejection. These are the headline performance credentials for the world’s most certified marine anti-glare screen. But what do these two figures actually mean, and why are they different from each other?
The answer lies in the fact that glare and heat are two distinct physical problems, caused by different properties of sunlight, and addressed by different mechanisms within the screen material. Understanding the difference matters for anyone specifying solar protection for a navigation bridge, because a product that performs well on one measure does not automatically perform well on the other.
This guide explains exactly what each figure means, how it is measured, and why both are critical to crew safety and vessel performance on the navigation bridge.
Sunlight Is Not a Single Problem
To understand the difference between glare reduction and heat rejection, it helps to understand what sunlight actually consists of when it passes through a navigation bridge window.
Sunlight reaching the bridge window is made up of three distinct components:
- Visible light, which is the portion of sunlight that the human eye can see. This is the source of glare and brightness that impairs the vision of bridge officers during long watches.
- Infrared radiation, which is the portion of sunlight that carries heat. Infrared radiation is invisible to the human eye but passes through glass and raises the temperature inside the bridge environment.
- Ultraviolet radiation, which is also invisible and carries harmful UV energy that causes eye damage, skin damage, and degradation of bridge equipment and fittings over time.
SOLASOLV® screens are engineered to address all three components simultaneously, but each component requires a different type of filtering, and the percentage reduction achieved for each one is different. This is why the glare reduction figure and the heat rejection figure are not the same number.
What Does 93% Glare Reduction Mean?
Glare reduction refers to the reduction in visible light transmission through the screen. When SOLASOLV® achieves up to 93% glare reduction, it means that the screen filters out up to 93% of the visible solar radiation that would otherwise pass through the navigation bridge window in full sunlight.
The remaining 7% of visible light that passes through is enough to maintain a clear, natural outward view through the window at all times. This is a critical design requirement for navigation bridge window products. Unlike opaque blinds or heavily tinted glass, SOLASOLV® screens allow the officer of the watch to see the sea, other vessels, navigation aids, and the horizon clearly, even when the screen is fully deployed. This is precisely what IMO navigation bridge visibility regulations require.
Why 93% Glare Reduction Matters for Bridge Safety
On a commercial vessel, uncontrolled sun glare on the navigation bridge creates a direct safety risk. It causes:
- Impaired forward visibility, making it difficult for officers to see the sea surface and detect other vessels, obstructions, and navigation hazards
- Reflections on electronic displays including ECDIS, radar, and chart plotters, making instrument readings difficult to interpret accurately
- Rapid onset of eye strain and visual fatigue, which reduces alertness and reaction time during long watch periods
- Increased risk of human error on the bridge, particularly during manoeuvring in busy or restricted waters
By reducing visible light transmission by up to 93%, SOLASOLV® eliminates the source of these problems while preserving the full outward visibility the officer needs to navigate safely. For a deeper understanding of how glare affects crew performance, see our article on glare, heat and fatigue on the navigation bridge.
What Does 87% Heat Rejection Mean?
Heat rejection refers to the reduction in solar infrared radiation passing through the screen. When SOLASOLV® achieves up to 87% heat rejection, it means that the screen blocks up to 87% of the solar thermal energy that would otherwise enter the bridge environment through the window.
Infrared radiation is not visible to the human eye, but it is the primary cause of solar heat gain inside an enclosed space. On a navigation bridge with large windows facing the sun, uncontrolled infrared radiation raises the ambient temperature significantly, creating a working environment that is uncomfortable, fatiguing, and in extreme cases, operationally unsafe.
Why 87% Heat Rejection Matters for Vessel Operations
Excessive heat on the navigation bridge has consequences beyond crew discomfort:
- It forces the vessel’s air conditioning and ventilation systems to work harder to maintain an acceptable temperature, increasing power consumption and fuel costs
- Prolonged exposure to heat accelerates fatigue in bridge officers, compounding the effect of visual fatigue caused by glare and reducing overall crew alertness
- Elevated temperatures can affect the performance and longevity of sensitive bridge electronics including navigation computers, radar systems, and communication equipment
- In hot climate regions such as the Gulf of Mexico, the Arabian Gulf, and Southeast Asian waters, uncontrolled solar heat gain can make the bridge environment genuinely difficult to work in during the hottest parts of the day
By rejecting up to 87% of solar infrared radiation, SOLASOLV® screens significantly reduce the solar heat gain entering the bridge, helping to maintain a cooler, more comfortable working environment and reducing the energy demand placed on the vessel’s cooling systems.
What About UV Rejection? The Third Performance Measure
In addition to glare reduction and heat rejection, SOLASOLV® screens also achieve up to 99% UV light rejection. Ultraviolet radiation is the third and often overlooked component of sunlight reaching the bridge window.
UV radiation causes cumulative damage to the human eye over time, contributing to conditions including cataracts and macular degeneration. It also degrades plastics, fabrics, and electronic components on the bridge, accelerating the wear and deterioration of fittings and equipment.
At up to 99% UV rejection, SOLASOLV® screens provide the highest level of protection against this component of sunlight, effectively eliminating UV radiation as a factor in both crew health and equipment longevity on the navigation bridge.
SOLASOLV® Performance Summary
The table below brings together all three performance measures and explains what each one addresses:
| Performance Measure | SOLASOLV® Rating | What It Addresses |
|---|---|---|
| Glare reduction | Up to 93% | Visible light causing eye strain and impaired forward visibility |
| Heat rejection | Up to 87% | Infrared radiation causing heat gain and elevated bridge temperature |
| UV rejection | Up to 99% | Ultraviolet radiation causing eye damage and equipment degradation |
| Outward visibility | Fully maintained | Clear, undistorted view through the screen at all times |
Why Are the Glare and Heat Figures Different?
A common question from buyers seeing these figures for the first time is why the glare reduction percentage is higher than the heat rejection percentage. If the screen is filtering sunlight, why does it not achieve the same reduction for both?
The answer lies in the physics of the screen material. Glare and heat are carried by different wavelengths of light. Visible light, which causes glare, sits in a narrower band of the solar spectrum. Infrared radiation, which causes heat, covers a much broader band of wavelengths. This means that filtering out a high proportion of visible light is technically achievable at a different rate to filtering out infrared radiation across its much wider spectrum.
SOLASOLV® screens are engineered to optimise the filtering of both spectra within the constraints of a see-through film that must still allow the officer of the watch to see clearly through the window. The result is a product that achieves 93% glare reduction and 87% heat rejection simultaneously, while maintaining full outward visibility. No opaque blind or heavily tinted glass can match this combination of performance and visibility.
What This Means When Specifying Marine Anti-Glare Screens
For shipbuilders, procurement managers, and vessel owners specifying navigation bridge window products, understanding these figures has direct practical implications.
A product that only addresses glare but not heat will still result in a hot, uncomfortable bridge environment, increasing fatigue and energy costs. A product that only addresses heat but not glare will still leave officers of the watch struggling with eye strain and impaired visibility. Only a product that addresses both simultaneously delivers the full safety and operational benefit that modern navigation bridge environments require.
SOLASOLV® screens achieve both, independently and simultaneously, in a single see-through film that meets IMO navigation bridge visibility requirements and is Type Approved by Lloyd’s Register, DNV, ABS, and RINA. Full technical performance data for all SOLASOLV® screen film colours is available on the Solar Solve technical information page.
Both of Solar Solve’s core anti-glare screen products deliver these performance figures. SOLASAFE® (with cassette) is the cassette-mounted version preferred for newbuild specification, while SOLAROLA® (without cassette) provides the same performance in a non-cassette format suitable for both newbuilds and retrofit installations.
Frequently Asked Questions
What does 93% glare reduction mean on a marine anti-glare screen?
It means the screen filters out up to 93% of the visible solar radiation passing through the navigation bridge window. The remaining visible light is sufficient to maintain a clear, undistorted outward view at all times, meeting IMO navigation bridge visibility requirements while eliminating the sun glare that causes eye strain and impairs instrument visibility.
What does 87% heat rejection mean on a marine screen?
It means the screen blocks up to 87% of the solar infrared radiation that would otherwise pass through the window and raise the temperature inside the bridge. This reduces solar heat gain, lowers the demand on the vessel’s cooling systems, and helps maintain a more comfortable and productive working environment for bridge crew.
Why is the glare reduction figure higher than the heat rejection figure?
Glare is caused by visible light, which covers a narrower band of the solar spectrum. Heat is caused by infrared radiation, which covers a much broader range of wavelengths. Filtering a higher proportion of visible light is achievable at a different rate to filtering infrared radiation across its wider spectrum. Both figures are optimised within a film that also maintains full outward visibility through the window.
Do SOLASOLV® screens maintain a clear view while reducing glare and heat?
Yes. SOLASOLV® screens are see-through by design. Unlike opaque blinds or tinted glass, the screen maintains a clear, undistorted outward view at all times, even when fully deployed. This is a fundamental requirement of IMO regulations for navigation bridge window fittings, and it is what distinguishes SOLASOLV® from non-specialist window covering products.
What UV protection do SOLASOLV® screens provide?
SOLASOLV® screens achieve up to 99% UV light rejection, protecting bridge crew from ultraviolet radiation that causes cumulative eye damage, and protecting bridge electronics and fittings from UV-related deterioration and degradation over time.
Where can I find full technical performance data for SOLASOLV® screens?
Full technical performance data including glare reduction, heat rejection, UV rejection, and visible light transmission figures for all available SOLASOLV® screen film colours is available on the Solar Solve technical information page at solasolv.com/technical-information/.
