As you know, you cannot tan at home, even if the room is full of sunlight. The bronze tint to the body will be given by radiation called ultraviolet. This is the part of the spectrum located above the visible range. Infrared heaters for the home are often confusedly called ultraviolet heaters. This is fundamentally wrong. Ultraviolet heaters are not used to produce heat. But there are devices that have a dual function. Ultraviolet light gives the skin a golden tint in solariums and kills germs in medical institutions. Fashionistas wear glasses for a reason when they sit in a UV radiation device.
Features of the ultraviolet spectrum
The ultraviolet spectrum is notable for two qualities:
- Kills germs.
- Gives the skin a bronze tint.
Two qualities force the manufacturer to use different methods for producing ultraviolet radiation. First of all, energy is used for disinfection, and secondly for heating.
This practice exists due to the physical characteristics of the range. Let's figure it out. Every heated body emits energy. For example, the Sun sends waves in a wide spectrum, starting with infrasound and extending the rays to infinity on the frequency axis. Some of the radiation is filtered by the atmosphere. A select share reaches the ground: ultraviolet light takes away the ozone layer. The yellow disk visible to humans is a small fraction of the energies sent to humanity by the luminary. Most of them are located in the invisible range. At the bottom along the frequency axis is the infrared spectrum, at the top is the ultraviolet spectrum.
Important! The star's radiation density has the shape of a hill with its forehead shifted to the left. The visible part of the spectrum is located on the right slope. Hence the volume of the ultraviolet part is lower than the infrared.
Each heated body exhibits a pronounced maximum of radiation. As the temperature increases, the frequency of the luminescence peak wave increases. In everyday life, it is much easier to heat a spiral red-hot and begin to emit in the infrared range.
The emission spectrum is a continuous line, gently falling on both sides of the maximum. It turns out to be a mountain. An infrared heater also emits relatively weakly in the ultraviolet range. In practice, it is difficult to heat a metal before emitting radiation in the ultraviolet range. It is not necessary. Infrared heaters have high efficiency, which suits people.
More information about IR heaters
IR radiation itself was discovered in the nineteenth century, when the astronomer Herschel tried to cope with the heating of the equipment he used to observe the Sun. It was useful for about 100 years, until another creative person, the German Gunther Schwark, patented the world's first IR heater, and he also made a skilled copy with his own hands.
Regardless of the time that has passed since its invention, the principle of operation of the heater has not changed to this day. Only the design has been improved and new methods of heating the heating element have been added.
Device and principle of operation
The main structural elements of the heater are:
- heating element, it will emit IR waves;
- reflector - used to prevent radiation from the heater from spreading throughout the room, in other words, the reflector allows the heater to function directionally. In most cases, the reflector is made of mirror-polished steel or aluminum;
- modern devices are equipped with thermostats, which allow you to regulate the heating operation;
- In addition, the design must include sensors that allow the device to be turned off if it overheats.
The operating principle of infrared heating (also known as infrared heating) is fundamentally different from other types of home heating. If, for example, the radiators of the heating system heat the air space in the room, then the infrared heater heats the surface that is hit by invisible rays.
It is precisely on this basis that the effect of turning on the heater is noticeable instantly. The air space between the object and the emitter practically does not reduce the thermal effect, it only easily dissipates it.
Classification of infrared heaters
The principle of operation of all heaters is the same, so the main criterion by which classification is carried out is the method of heating the heating element.
It is possible to select the following types of heating elements:
- electrical - the principle of operation is that when it is plugged into the network, current begins to flow through the conductor, it heats up and begins to emit infrared waves;
- Gas or liquid IR heaters are quite often used in the industry.
As for the appearance, there are not so many options for implementation.
Popular heaters are:
- paintings - under such conditions, in addition to heating, they are also an element of room decor;
- narrow film - using a narrow film it is possible to create a warm floor, for this purpose the film is under the floor covering. The dimensions of the conductor are selected so that the floor temperature does not exceed 24-26? C, otherwise there will be inconvenience when walking.
Note! There is nothing that prevents the film from being mounted on the ceiling or wall for local comfort. This solution will look worse than a painting-heater, but the price will be much lower.
- portable devices on an adjustable-height support . It is always possible to place such a heater next to you.
Attention should also be paid to the heating temperature of the thermoelement; depending on this, it may glow or not emit visible light.
In this matter, everything depends on the wavelength; if you classify devices according to this parameter, then it is possible to distinguish 3 types:
- short-wave - they have a “hot temper” and emit IR waves with a length of about 0.7 - 2.5 microns. The heating element may turn bright white during operation. Such wonderful devices can also be used in industry, since the temperature of the thermoelement can be more than 800? C;
- with medium wavelength (2.5 - 50 µm). The temperature maximum of the surface is limited to 600? C, along with this the color ranges from dark to bright red;
- devices operating in the wavelength range of the order of 50 – 500 microns do not change color during operation. High surface temperature is limited to 300?C.
What doctors say
If the choice is made in favor of infrared heating, then it is necessary to think about the effect of radiation on the human body.
Please note that:
- a small wave enters the body to a fairly enormous depth (of the order of several cm) and affects the internal organs;
- long-wave radiation - retained by moisture contained in the subcutaneous moisture. The nature of phenomena such as heat stroke is explained precisely by this.
The wavelength range of 7-14 µm can be considered as one in which a large absorption of radiation by the body occurs (the peak is noted around the value of 10 µm). Warming used in medicine uses precisely this range of radiation. But it is undesirable to stay in the area of short-wave radiation for a long time.
IR heating operating in the long-wave range can affect a person with virtually no restrictions on duration. Despite the fact that, of course, a lot depends on the installation distance of the heater, if you sit touching it all day, then unpleasant consequences are likely.
To ensure that nothing threatens your health, you should adhere to the following guidelines when organizing infrared heating:
- high radiation power should be reduced to the level of 350 W/m2;
- if the surface of the thermoelement in the heater exceeds 100? C, then the high temperature of the surface of the object falling into its field of action must be 45? C;
- If the thermoelement does not reach a temperature of 100, then objects should not be heated to a temperature above 35? C.
Note! If you allow the body to be exposed to IR radiation of high or medium intensity for a long time, then troubles are guaranteed. The origin of the burns is also likely.
UV exposure
It is difficult to heat metal to produce ultraviolet radiation under normal conditions; other methods are used. This is not the only reason for eliminating ultraviolet heaters from use. Rays located above the visible spectrum have a detrimental effect on microbes.
The skin tans under the influence of ultraviolet rays, but will receive burns. A strong radiation source will be required; this mainly applies to artificial solariums. Long-term exposure causes mutations and less commonly leads to skin cancer.
Ultraviolet radiation is much more dangerous for the eyes. Corneal burns are possible. Most of the spectrum is absorbed by the lens and does not reach the retina. Ultraviolet is perceived by humans as a weak gray or purple glow. Mild corneal burns are not too dangerous. The eye is restored to 100%. Otherwise, a person exposed to the sun would risk his health. However, disinfection with ultraviolet lamps in the hospital is carried out in the absence of patients.
Ultraviolet light has also been found to have a positive effect. Triggers the synthesis of vitamin D, preventing the development of rickets. Long-term absence of sunlight has a detrimental effect on the body, causing seasonal depression. The fact has been studied and scientifically proven; interest in full-spectrum lamps is awakening in the world. Glass filters ultraviolet, distorting the spectrum, cutting off above the visible range.
Types and areas of application of UV devices
Ultraviolet lamps are divided into three groups according to functionality:
- open type - lamps of significant power for disinfecting premises from which people, animals and plants are previously removed;
- closed type - powerful lamps located in a special insulated chamber through which air from the room with people is passed for disinfection;
- special purpose – low-power ultraviolet lamps for physiotherapeutic procedures, including at home.
Based on their design, UV heaters are classified into the following types:
- stationary;
- portable tripod version;
- portable compact.
Stationary ultraviolet heaters
UV devices of this type include devices located in separate chambers to disinfect the air passed through them, as well as wall and ceiling devices that are turned on periodically in the absence of people.
Some models (recirculators) can also be operated in the presence of a person. The air in them is disinfected by forced circulation through the body of the device with UV lamps located inside.
The power of such devices is selected in accordance with the dimensions of the room or the throughput of the camera.
Stationary UV devices also include means of water disinfection in swimming pools, produced due to operation under water in sealed housings. Ultraviolet irradiation of water is used in addition to treating it with chemical reagents to achieve better cleaning results.
Water is passed through a long channel with a small cross-sectional area, subjected to prolonged UV exposure. This design ensures a high degree of water disinfection and eliminates the formation of salt deposits on the walls of the device, which impede the disinfection process. The kit includes brackets for mounting on pool walls.
One such device is designed for a pool with a volume of up to 100 cubic meters.
Portable tripod UV devices
UV devices with a tripod design are used for regular disinfection of premises in medical and children's institutions, as well as in physiotherapy rooms for general and local UV irradiation for therapeutic and preventive purposes. Their weight is insignificant and allows you to transport the equipment to the place where it is needed.
In addition to disinfection, UV devices of this type are used to achieve vitamin-forming, anti-inflammatory, immunomodulatory and analgesic effects in patients of medical and preventive institutions.
Portable compact ultraviolet heaters
An example of a compact UV heater is a blue lamp with a reflector, placed for ease of use in a dielectric housing with a handle - a Minin reflector. This device has been successfully used in medicine for many years for local heating in the treatment of inflammation of the hearing and respiratory organs. The radiation power of the reflector is small - limited to the amount necessary for the procedures, the duration of the session is also strictly regulated, so this device does not have a negative effect on the human body, and the combination of the effects of heat and ultraviolet radiation on the body reduces the rate of recovery by several times.
Other devices using ultraviolet light
Devices for sterilization and storage of medical instruments and cosmetic devices can also be made using the disinfecting properties of ultraviolet radiation. In this case, the material used to make the instruments does not matter; products made of metal, plastic, or a combination are disinfected with equal quality. Short processing time - 15-20 minutes, compactness, efficiency and cost-effectiveness - this is not the whole list of advantages of these devices over conventional thermosterilizers.
In modern dentistry, light-curing fillings are widely used, which occurs after targeted exposure of the material to a narrow beam of UV radiation.
Important! When exposed to UV rays, eye protection is required to avoid corneal burns.
Ultraviolet heaters are indispensable in SPA salons for the safe and comfortable use of wet towels and tampons, which are simultaneously heated and disinfected in special heaters using UV radiation.
In everyday life, UV heaters are often used in the form of devices for drying shoes from the inside. In this case, not only moisture is removed, but also antibacterial treatment of the hard-to-reach inner part of the shoe with the destruction of bacteria - the source of fungal diseases and unpleasant odors.
Automatic detectors for determining the authenticity of banknotes also use UV rays, in the light of which modern elements of protecting banknotes from counterfeiting appear.
A car is an everyday companion for most people, and its diagnostics today are also carried out using ultraviolet radiation. For this purpose, ultraviolet detector flashlights are produced, with the help of which it is easy to detect leaks of antifreeze from the cooling system of a car engine or freon from a car air conditioning system.
Such a detector can also determine the location of an oil leak if a special UV dye is added to the lubricant, which does not change its technical characteristics.
This is interesting: How to choose a diesel heater: where it can be used, types, principle of operation
How do you get ultraviolet light?
There is a galaxy of ultraviolet lamps. Special glass is used; standard silicone glass is not permeable. This is far from the only and certainly not the most promising method of producing ultraviolet radiation:
- Gas discharge lamps. When the ionization process begins, mercury's electron energy levels are arranged in such a way that the disintegration of molecules causes the appearance of ultraviolet quanta.
- The excilamp does not differ from the previous class except for the pronounced maximum of radiation located in the near ultraviolet range, for example, 282 nm. The active substances are xenon bromide. Most noble gas halides are used. The principle of operation is based on discharge and production of plasma that actively emits ultraviolet radiation. The scheme for creating ionization is different.
- Luminescence is a secondary process. The active substance is bombarded with electrons and begins to glow in the process. The phenomenon is based on changes in the energy states of electrons. The shade of the glow depends on the composition of the phosphor; it is reasonable to select the components, trying to obtain the ultraviolet range.
- LEDs are considered a promising direction. The efficiency reaches 99%, in addition, the width of the emitted ultraviolet spectrum can be chosen as small or large as desired. Small size, fault tolerance and relatively simple processing methods will allow the formation of ultraviolet radiation sources of any type. The principle of operation is based on the processes occurring in the pn junction. The frequency of radiation is determined by the composition of energy states in the semiconductor.
- Lasers are a separate topic; they are not used in everyday life. The main feature is the coherence of radiation. The ultraviolet spectrum is narrow, the waves are of the same phase. For heating purposes, no tricks are needed, nor is there any need to kill microbes. Such precise parameters of the ultraviolet radiation source are used in technology, and less often in medicine.
Devices whose operating principle is based on ultraviolet radiation
Today you can find many devices called ultraviolet heaters. But they are not. For the most part, these are a variety of lamps of various designs. They are used in medical institutions, beauty salons, and are used to carry out disinfection procedures:
- sterilizers - heaters;
- bactericidal lamp;
- shoe dryer;
- towel warmer.
Germicidal lamp
Many people probably remember being treated at home with blue glowing lamps when they were children. For colds in the ENT organs, “warming” procedures were carried out, lasting several minutes. Their work is based on disinfection, for example, of the nasal mucosa during a runny nose, with a warming effect. With a combination of heat and ultraviolet light, the patient’s recovery occurs many times faster.
Shoe dryer
The device is a block equipped with a heating element and a lamp with ultraviolet radiation built into the device's office. Such devices make our life easier, thanks to them we can:
- dry shoes quickly;
- destroy pathogenic bacteria, fungi and microbes,
- get rid of unpleasant odor;
- maintain the original shape of the shoes.
Sterilizer-heaters
Similar equipment is used in beauty salons and hairdressing salons to disinfect various devices: scissors, combs, files used in this area, but which cannot be subjected to other cleaning methods, such as boiling. Such equipment combines the functions of a heater and an ultraviolet sterilizer.
Types of ultraviolet heaters
The only existing type of ultraviolet heater is a device familiar to everyone. This is a blue lamp for the treatment of ear diseases, less often a runny nose. The operating principle of an ultraviolet heater is based on local disinfection and increasing the temperature of the irradiated area of the body. In this case, the ear. The synergistic effect facilitates the course of the disease and promotes rapid elimination.
In other cases, ultraviolet light complements the effect of heat obtained in other ways. It's not uncommon for boots to smell terrible in the summer. It’s just that inside, at a temperature of 36 degrees Celsius, a myriad of bacteria find shelter and conditions for the reproduction.
Can you guess how an ultraviolet shoe warmer works? Like a regular infrared heat source, supplemented with a special lamp that provides disinfection. No moisture, no smell. It turns out to be a blue lamp for the ear, but much more powerful.
What types of ultraviolet heaters are there? Perhaps medical, for a specific purpose. For example, for the oral cavity. Ultraviolet light is not used for heating. It's simply dangerous for your eyesight.
Rules for installing an IR heater
If you use a portable heater, there will be no special problems with its installation - you just need to place it at the desired distance and adjust the height. It is somewhat more difficult to install a wall or ceiling heater correctly.
When installing, you need to take into account that despite the use of a deflector, the space around the heater still warms up. Therefore, the base (wall, ceiling) must withstand temperatures of about 80ᵒC without consequences.
Instructions for installing a ceiling infrared heater will look something like this:
- Holes for hangers are marked on the ceiling and holes are drilled;
- then a ring screw is screwed into the holes;
Note! All elements necessary for installing the heater are supplied with it.
- then the heater itself is suspended on a chain, its horizontalness is adjusted and it is checked whether the minimum distances to the ceiling surface are ensured.
In this example, the heater is suspended directly from ring screws
Before connecting it to the network, manufacturers recommend additionally wiping the heating element with regular medical alcohol so that nothing interferes with heat radiation.
Note! The thermostat should be placed at a distance of 1.5-1.8 m from the floor surface. It must not fall within the operating range of the device.
The thermostat must not be within the heater's operating range.
Installing a wall-mounted model is even easier - just attach a couple of brackets to the wall and simply hang the device on them. The only thing that needs to be controlled is the distance from the back of the device to the wall. For ventilation, it is enough to provide a gap of about 2 - 5 cm, depending on the power of the device.
During installation, special attention is paid to maintaining the distances from the device to the surface of enclosing structures and people. These distances are normalized depending on the power of the device. For example, for a 0.8 kW ceiling heater, the minimum distance to a person’s head should be about 70 cm, and for a powerful 4 kW heater – already 2.5 m.
Minimum recommended distances when installing a ceiling heater
Where is ultraviolet light used?
Light seals are a familiar phrase. The miniature pistol has a special orange filter that protects the doctor’s eyes. It was already mentioned above that ultraviolet radiation can burn your eyes. There is a laser inside the device, coherent radiation is simply deadly for the organs of vision. This is an unnatural effect not found in nature. The radiation of the Sun, even to a first approximation, is not coherent.
The main problem with swimming pools is blooming. Standing water will quickly turn into a swamp if special measures are not taken. A specially designed ultraviolet lamp will ensure a low level of reproduction of bacteria and other unwanted guests from the microcosm. The operating principle of the devices is no different from fluorescent lamps, except that the design is sealed and the working gas is different. It is appropriate to recall that the difference between lighting devices ultimately comes down to the structure of the energy states of the electrons. The working substance is pumped with energy and radiates.
Under the influence of ultraviolet radiation, ionization of gases occurs. This is the basis of the method for measuring air purity. When the concentration of harmful gas molecules exceeds the permissible level, the current of ions triggers an alarm.
Tanning salons are popular and use ultraviolet rays.
