Frequently Asked Questions:
In food processing industries the presence of biological contaminants causes a number of problems and amongst other things potentially increase health risk to the consumer. Here are the notable advantages of surface disinfection by irradiance:
• Delays degradation of product quality
• Extends product’s shelf life
• Reduces the numbers of halts in production line for cleaning conduct
• Avoids the use of disinfection chemical products
The design and construction of a phytosanitary disinfection light system in the visible and non-visible spectrum is custom made in accordance with the specifications of the customers’ projects and their existing equipment. As a matter of fact, the configuration of the disinfection system will be different depending on the type of germs to be treated, the conveyor speed and the dimensions of its belt.
The power density of light from any LED can be tested with a ‘solar power meter’. The units are usually expressed in W/m² or mW/cm².
This measurement describes, how concentrated the light is at a given point. In other words, it is the quantity of photons that are going through a given area of space.
Despite the fact that lumen or lux is normally used to measure LED illumination, it is not useful for plants. For growth and vital activities, we need to know Photosynthetic Photon Flux (PPF) . To know the efficacy of a light source on photosynthesis for growth and vital activities, we need to know PAR (photosynthetically active radiation), PPF (flux of synthetic photons) and the PPFD (the density of the flux of photosynthetic photons).
To allow photosynthesis to occur, an amount of light and intensity is required. The unit to express PAR is millimoles (of photons) per square meter per second (mmol/m2/s). Photosynthentically active radiation (PAR) is the available light required for photosynthesis to take place. The wavelengths of photosynthentically active radiation that plants can use are generally in the range of 400-700 nanometers (nm). Photosynthentically active radiation is absolutely essential for a plant to survive, and plants grow fastest in conditions of higher PAR. Plants germinate, grow, bloom, and produce fruit.
PPF denotes the measurement of all wavelengths useful present in a given light source for photosynthesis. Plants primarily use wavelengths of light between 400 and 700 nanometers to achieve successful photosynthesis. Wavelengths that correspond to blue and red are considered useful to photosynthesis. The light within this range is called photosynthetic active radiation (PAR). PPF represents the measurement of all the photons in this range. However, PPF by itself is not enough. Photosynthentically Active Radiation (PAR) is necessary to know how much useful light to photosynthesis is falling on the plants. The PPF of a lighting system does not denote the quality of the spectrum of light that plants receive. We have to know the Photosynthetic Photon Flux density (PPFD).
PPFD is the actual amount of PAR that falls on the plant. The unit is millimoles (of photons) per square meter per second (mmol/m2/s). It is important not take a single measure in one spot. Severals must be made and then do an average to have a better characterization of a light source.
Photosynthesis is the process used by plants to convert light and other elements (water and carbon dioxide) into chemical energy to fuel their organic activities. The production of oxygen obtained though this process which allows life on earth. Photosynthesis takes place mainly in plants’ leaves through the use of chlorophyll. In the photosynthesis process, the sun’s energy is then used to divide the water absorbed by the roots into different molecules like oxygen and hydrogen. As the plants “breath”, the oxygen is diffused back into the earth’s atmosphere, while the plant conserves the carbon dioxide and hydrogen, which it will later convert into energy and glucose. The glucose ends up contributing to the plant’s healthy development and growth, and some of it is stored in the fruits, roots, and leaves for later use.
Photosynthetic reaction centers are the core area of a plant responsible for capturing photons of light and transforming that into energy needed for growth. These centers are a combination of pigments, proteins, and other co-factors. All green plants have two photosynthetic reaction centers. One is called photosystem I and the other is called photosystem II. This area is responsible for the capture of the light into energy conversion. As photons are captured, an electron within the pigment (chlorophyll) is excited (gains more energy). As the electron becomes more excited, it generates more energy, which is then available to the plant for use in metabolic processes.
Also known as plant light, grow light acts as an artificial light used for indoor gardens by simulating sunlight to allow photosynthesis to happen. Grow lights achieve this by emitting electromagnetic radiation in the visible and non-visible light spectrum that simulates sunlight for photosynthesis.
High Intensity discharge lamps, otherwise known as HID lamps produce high-intensity light through an electric arc and a gas discharged electrical process. It is commonly used in hydroponic gardening.
A high-pressure sodium (HPS) light is a type of growth light that is commonly used for indoor gardening. This particular light stimulates plant growth by diffusing the portion of the electromagnetic spectrum that is ideal for the whole process of photosynthesis. However, they are very energy consuming.
Metal halide (MH) lamps are a type of high-intensity discharge (HID) lamp. Metal halide lamps produce light through an electric arc and a mixture of gaseous mercury and metal halides. It also light is used for indoor gardening. High output of light is expected and they are used whenever the gardener wants to keep his plants and short bushy. The emit a bluish-white light encourages plants to enter a vegetative growth stage. One downside to metal halide lights is that they do not emit in the red/orange portion of the light spectrum, which is necessary for plants to produce fruit. However, special metal halide lamps with an enhanced red-light spectrum has been developed.
A light-emitting diode (LED) is a small electroluminescent light. LED can emit specific wavelengths so the light can be more adaptable to a particular plant’s need. It is energy efficient light as they emit little to no heat. This allows plants not to suffer from overheating as well save on electricity (up to 75%). LED has become more popular as grow lights in the field of horticulture, urban farms and grow rooms. Also, they have larger lifespan as it can last up to 100,000 hours which is very suitable for the greenhouse and other indoor gardening.
It is a florescent bulb used for indoor gardening which has been around the 1950’s. It can be used in conjunction of previous model fixtures (T8 and T12). The light colors are based on temperature (e.g. 3000K, 6500K, etc.) Depending on the gardener wishes (green color depth, hardening level, etc.), several adjustments are required like choosing a T5 instead of a T8. For instance, bulbs with a 3000K (Kelvin) rating produce more light in the red spectrum, helping to encourage flowering. Bulbs with a 6500K rating provide a full spectrum of light and are ideal for overall growth.
Lumen is a unit that indicates a basic measurement for illumination. However, it suits a human perception of light and not the needs of the plants. In horticulture, it is important to grasp the basics of lighting to calculate the exact light exposure that plants and seedlings require to thrive. Proper light exposure can prevent harmful pests and fungi from invading the roots and preventing proper growth.
It is the unit used to measure electromagnetic waves (or photon) coming from a light source. The unit is one million times smaller than 1 mm. For instance, the visible wavelength stems from 400 nm to 700 nm and this is referred to as photosynthetically active radiation (PAR). Violet is closer to 400 nm and red is closer to 700 nm. It is an important unit in that allows to characterize the wavelengths that compound a light source. From there, we know what phase of the photosynthesis we want to stress, either the vegetative, the flourishing phase or both. The unit is also used in the PAR measurement.
Blue light is a short wavelength in the electromagnetic spectrum which ranges around 450 nm and produces more energy than most wavelengths in the visible light and contains more photons essential for maximum plant growth. It is useful for the plants vegetative phase. Blue is responsible for the chlorophyll A production, leaves and stems strength. NASA is exploring the possibility of using blue light system to grow plants in space.
Red corresponds to the region of 600 nm to 700 nm of the visible light. It is essential for the photosynthesis as it allows seeds and roots to grow in the plant’s early life. Also, red is responsible for the flower and fruit production. Colors on the far ends of this spectrum play a key role in the health and propagation of plants.