Surface illumination is the quantity
∆Φ - luminous flux incident on the surface of the area
∆S, Figure 3.3. If ∆Φ = 1lm,
∆S = 1m, illumination = 1 lux, (lux).
That is, 1lx = 1lm: 1m2.
Figure 3.3
3.2.5 Law of illumination
Elementary transformations make it possible to establish the relationship between the surface illumination E and the distance R and the angle of incidence of light j on the surface, Figure 3.3, in the form:
Formula (3.9) is called law of illumination .
3.2.6 Luminosity of the emitting surface, m
So far, we have considered point light sources. Every real source has finite dimensions. Let a luminous area of area DS, Figure 3.4, emit light into a hemisphere, which corresponds to a solid angle DW = 2πavg. Let us denote by DΦ PS the luminous flux emitted by the area DS into the hemisphere.
The value, lm/m2 is called Withdecency radiating areaDS.
According to Figure 3.4, luminosity M is numerically equal to the luminous flux emitted from a unit area of the luminous surface into a solid angle of 2π steradians.
Figure 3.4
3.2.7 Brightness of the luminous surface, l
Let a luminous surface of area DS emit a luminous flux DΦ into a solid angle DΩ, the symmetry axis of which makes an angle Θ with the normal to radiating surface, Figure 3.5.
Figure 3.5
Magnitude
,
(3.10)
according to , is called the brightness of the luminous surface.
3.2.8 Lambert's Law
In 1760, the German scientist Lambert showed that if the area DS not only emits light, but also ideally evenly scatters it in all directions, the brightness of the radiation L does not depend on the angle Θ included in (3.10).
According to Lambert's law
L L = const, (3.11)
for any Θ included in (3.10).
Elementary transformations, , show that for a Lambertian source, the relationship between the luminosity of the emitting surface M L and its brightness L L has the form:
M L = L L × π (3.12)
3.2.9 Light exposure, ns
Light exposure H C is the product of the surface illumination E and the time t during which the surface is irradiated. A-priory,
H C = E × t, (lx × s) (3.13)
At the end of Section 3.2, we present in Table 3.2 the main photometric characteristics, analytical expressions for them and dimensions in “S I“.
Table 3.2 List of main photometric characteristics.
|
Name of photometric quantities |
Analytical expression |
Dimension in “SI” |
|
The power of light |
Candela, (kd) |
|
|
Light flow |
Lumen, (lm) |
|
|
Surface illumination |
Lux, (lx), (lumen per square meter), (lm/m). |
|
|
Luminosity of the emitting surface |
Lumen per square meter (lm/m) |
|
|
Luminous surface brightness |
Candela per square meter, (cd/m) |
3.3 Energy characteristics of optical radiation
3.3.1 Energy exposure, N E
A value equal to the ratio of the energy of radiation DW incident on a surface to the area of this surface DS:
,
(3.14)
3.3.2 Radiation flux, F E
A value equal to the ratio of the radiation energy DW transferred by radiation to the transfer time of this radiation Dt
F E = , (W), (3.15)
called radiation flux.
3.3.3 Energy luminosity Є (integrated emissivity)
The integral emissivity is equal to the ratio of the radiation flux F E to the area DS I from which this flux is emitted:
3.3.4 Surface irradiance, Є O
A value equal to the ratio of the radiation flux F E to the area DS P on which this flux falls and is absorbed
Bibliography
Ignatov A.N. Fundamentals of optoelectronics. Part 1. Emitting and photo-receiving devices. – Novosibirsk, 1988.
Ignatov A.N. Fundamentals of optoelectronics. Part 2. Liquid crystal and electroluminescent indicator devices. – Novosibirsk, 1989.
Selivanov L.V. Fundamentals of optics. Part I. - Novosibirsk: SibGATI, 1995. – 54s
Selivanov L.V. Fundamentals of optics. Part II. – Novosibirsk: SibGATI, 1995. – 56s.
Selivanov L.V. Fundamentals of optics. Part V. - Novosibirsk: SibGATI, 1997. – 56s.
Selivanov L.V. Fundamentals of optics. Part IV. – Novosibirsk: SibGATI, 1997. – 63s.
Goss F., Hanchen H. Ann. Phys. Ser. 6, I. – Leipzig, 1947 – 333s.
Hansperger R. Integral optics. Translation from English. – M.: MIR, 1985. – 380s.
Mahlke G., Gessing P. Fiber optic cables. Translation from English. – Novosibirsk: PUBLISHER, 1997. – 264s.
Cheo P.K. Fiber optics. Translation from English. – M.: Energoatomizdat, 1988. – 279s.
Gower D. Optical communication systems. Translation from English. – M.: Radio and Communications, 1989. - With.
Mason U. Physical acoustics, vol. 3, part B. Translation from English. – M.: MIR, 1968. – 320s.
Selivanov L.V. Fundamentals of optics. Part III. – Novosibirsk: SibGATI, 1995. – 44s.
Landsberg G.S. Optics. – M.: NAUKA, 1976. – 926s.
Physical quantities. Directory / edited by Grigrieva I.S., Meilikhov E.Z. – M.: Energoatomizdat, 1991. – 1232s.
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Luminous flux is light energy emitted by a point source. Since it depends on the distance, it is expressed in spatial angles.
Lumen is a unit of measurement of the power of light radiation, which is estimated by the sensation of light to the human eye.
Unit of measurement luminous flux Lumen can be thought of as the total amount of light. For example, a 40 W incandescent lamp will create a luminous flux corresponding to 415 lumens, a fluorescent lamp will create a flux of 3200 lumens. Place any optical system around the light source, the amount of light (lumens) will be the same. Thus, if the number of lumens is not written on a non-directional light source, then it is not clear how it will illuminate.
Illumination and brightness
Illuminance is the amount of light, it quantifies light, which falls on a particular surface area of the body. It depends on the wavelength of light, because the human eye perceives the brightness of different wavelengths of light differently, in other words, different colors.
Illuminance is calculated for different wavelengths separately. People perceive the brightest colors as:
- green - light with a wavelength of 550 nanometers;
- yellow orange. They are located next to it on the spectrum.
Light coming from red, blue and purple flowers, have a short or long wavelength, so they are perceived as darker. The concept of illumination is often correlated with the concept of brightness.
When lighting an area with the same lamp, a large area will be less illuminated than a small one.
Difference between brightness and illuminance
The Russian language gives two answers to the question of what brightness is. Brightness means a characteristic of luminous bodies, that is, a physical quantity. It also defines a subjective concept that depends on many factors, for example:
- structural features of human eyes;
- amount of light in the room.
The less light there is environment, the brighter the light source appears to us. You should distinguish between brightness and illumination and remember the following:
- brightness is the light that is reflected from the surface of a luminous object;
- Illuminance is the light that falls on the illuminated surface.
In astronomy, brightness includes two concepts, where stars emit and planets reflect. In this science, stellar brightness is measured on a photometric scale, and the greater brightness of the star is correlated with a smaller value. The most negative values are bright stars.
The unit of luminance (candela per square meter) is used for applied or physiological purposes.
The lux unit is used to calculate light levels. One lux is equal to one lumen per square meter. The foot-candle is also used to measure illumination. She is consulted in the fields of cinema and photography and some others. The foot is in the name because the foot-candle means the candela illumination of a square foot of surface, measuring in one foot intervals.
Photometer
A photometer is a device that measures illumination. The light is sent to a photodetector, then converted into an electrical signal and measured. There are photometers that work on a different principle. Mostly photometers show light levels in lux, but there are also those who use other units. Those photometers, also called exposure meters, are involved in determining shutter speed and aperture, thereby helping photographers and cameramen. In addition, photometers are used to determine the level of safe illumination in other areas, for example, in crop production, in museums, where it is necessary to maintain the required illumination.
Safe flow of light at work
Working in a dark or dimly lit room can cause various health problems, be it blurred vision, depression or other physiological and psychological disorders. For this reason, in the workplace, as part of occupational safety regulations, minimum safe lighting requirements are included. The final measurement result produced by the photometer includes the area of light propagation. These indicators ensure sufficient illumination of the entire room.
Light flux and museum exhibits
The speed at which museum exhibits will deteriorate and fade depends on the illumination and the intensity of the flow from the light source. Museum workers are working to determine the illumination of exhibits. This is done in order to ensure that there is a safe amount of luminous flux on museum units, as well as to ensure a sufficient level of illumination for visitors while viewing the exhibit.
The illumination level can be measured with a photometer, which is not easy to do because it should be installed as close to the exhibit as possible, and this requires removing the protective glass, turning off the alarm and obtaining permission. This task is made easier in another way, which is often used by museum staff. Instead of a photometer, a camera is used, which is not a replacement for a photometer in situations where more accurate measurements of the found lighting problem are required, but it is quite enough to identify a deviation from the norm.
You can determine the exposure with your camera based on the light level readings. The exposure illumination level is easy to determine using simple calculations. Museum staff resort to a formula or use a table, where exposure is represented in illuminance units. When making calculations, do not forget that the camera absorbs a certain amount of light, so you should take this into account.
Before providing a plant with the light it needs for photosynthesis, you need to know how much each crop needs. Gardeners and plant growers know this. They measure light levels to make sure each plant gets the amount of light it needs. Photometers are often used for such procedures.
Photometers are also widely used in laboratory practice. For example, a range of samples is determined with the help of which chemical composition. A special class of such devices includes a flame photometer. He detects alkali metals in samples, such as sodium, lithium, potassium. To detect them, you need to burn the sample at high temperature and use a photometer to analyze the flame spectrum. This problem is much more difficult to solve in other ways.
Modern photometers convert light radiation into electrical impulses; they are recorded using the principle of an ammeter and voltmeter, and then converted into a computer format.
A photometer is an instrument covering many fields of knowledge, such as chemistry, molecular biology, physics, materials science and others. The photometer is widely used in industry, laser and optical products. In addition to the chemical laboratory, the photometer finds application in forensic laboratories.
Thus, from the above, you have learned about the units of measurement of light, which It is better to buy lamps with the specified number of lumens that the concepts of illumination and brightness differ, and the amount of light can be measured with a special device.
In the previous article we answered the question “how much light” is needed for general lighting. Now let's talk about how best to illuminate individual dark corners of the room: how many light bulbs and which ones will be needed to illuminate certain areas. Agree that the night light above the baby’s bed and the sconce above the sofa require different brightness.
- 1 of 1
On the picture:
Small and bold: even a miniature light bulb can provide the level of illumination you need.
Light level is the surface density of the luminous flux incident on an area of a given size. It is measured in lux (lx).
Analyzing the table
Select the premises you are interested in (column) and the type of activity (row). Find the recommended light level (listed in the first column).
| Levels illuminated ness, lux |
common room | Office, children's room | Bedroom | Kitchen, dining room | Entrance hall, corridor | Bathroom, toilet |
| 1000 | sewing | - | - | - | - | - |
| 500 | picture lighting | drawing | - | - | - | - |
| 300 | - | sitting reading, writing | - | food processing | cosmetics technical procedures |
- |
| 200 | reading; food | Board games | cosmetics logical procedures, reading while lying down |
eating, serving | toilet by the mirror | shaving, washing |
| 150 | ironing | selection of books | - | washing dishes | reception of guests | washing, washing |
| 100 | - | outdoor games | nursing | placing and retrieving products | - | - |
| 75 | cleaning | cleaning | cleaning | cleaning | dressing; cleaning | cleaning |
| 50 | - | dressing, sports | dressing, sports | - | - | - |
| 10 | TV | for orientation at night | for orientation at night | for orientation at night | for orientation at night | for orientation at night |
We measure the length of the lamp suspension. The expected power of the lamps depends on the length of the suspension: the closer the lamp is to the illuminated surface, the dimmer the lamps can be. Save energy - lower the lamp as low as possible!
In the photo: Beat Light lamp from the Tom Dixon factory, design by Dixon Tom.
Measuring the distance to the surface
Suppose you received some number - the value of the illumination level. So, to watch TV, the illumination level should be 10 lux, to read a book on the sofa, 200 lux is required, and when working at a desk or while cooking in the kitchen - about 300 lux.
Let's take the last figure and, using this example, calculate the required light intensity, and therefore the power of the lamps. To do this, we need to find out one more value: this is the estimated distance from the light bulb to the surface that needs to be illuminated. After all, if your chandelier hangs on a long suspension, you will need less lamp power than in the case of a lampshade directly on the ceiling. Let's say, in our case, the lamp in the kitchen will be located above work surface at a height of 45 cm
How to choose a lampshade?
Determining the intensity of light
We know the desired level of illumination and the distance from the light bulb to the surface. It remains to substitute the value into the formula
I = E * r²
Where
I - luminous intensity in candelas (cd);
E - illumination level (lx);
r is the distance to the light source (m).
As a result, we simply multiply the square of the distance (45 cm) by the illumination level (300 lux) and get I = 300*0.45*0.45. We obtain the desired value of luminous intensity (I) - in our case it is equal to 60.75 cd.
- 1 of 2
On the picture:
Many manufacturers offer the same model for different number lamps So it is not at all necessary to rely on the number of lamps when choosing a lamp - choose a design, and the number of horns can be increased!
Looking for the right light bulb
It is known that an incandescent light bulb for 1 W of power consumption has a luminous intensity of 1 cd, and in a fluorescent (energy-saving) lamp 1 W corresponds to approximately 5 cd. Therefore, to cook food with light, a 60-watt incandescent lamp or fluorescent lamp power 10-15 W.
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Often, lighting in a house or apartment is determined by a minimum of parameters. This is by design lighting fixtures and location. And even knowing about illumination standards, many simply do not take them into account. This is certainly not a critical error. But if you select lighting according to the rules and standards of illumination, correctly calculate how much light is needed for a certain room in an apartment, you can achieve a stable psycho-emotional and physical state for a person.
How many lumens are needed for 1m2
An integral part of a comfortable stay at home or at work is lighting. Few people know that the right light helps relieve psychological stress or, on the contrary, concentrate on work. But before moving on to calculations, it is necessary to understand the measurement values. Lumen (Lm) is a unit of measurement of luminous flux, Lux (Lx) - the illumination of a surface is measured in lux. 1 lux is equal to 1 lumen per square meter.
Calculation (measurement) of lighting intensity is carried out using a simple formula (AxBxC) in which:
- A – required illumination according to SNiP standards;
- B – room area (sq. m);
- C – Height coefficient.
The height coefficient is a correction value and is calculated depending on the height of the ceiling. 2.5 and 2.7 – coefficient equal to one; if 2.7 and 3 meters - 1.2; ceilings with a height of 3 and 3.5 meters - 1.5; from 3.5 to 4.5 meters – coefficient is 2.
Table of illumination standards according to SNiP in lux (Lx):
|
For office premises |
Norm (degree) of illumination |
For residential premises |
Illumination standards |
|
Office using computers |
Living rooms, kitchens |
||
|
Drawing office |
|||
|
Meeting room |
Bathroom |
||
|
Ladder |
Ladder |
||
|
Library |
|||
|
Utility rooms |
|||
|
Wardrobe |
We make a calculation. Suppose you need to find out the required amount of light for a children's room, the area of which is 15 square meters, with a ceiling height of 2.7 m. For accuracy, we use a calculator. Multiply the illumination value by square meters and by the height coefficient - 200 x 15 x 1 = 3000. Accordingly, the luminous flux should be 3000 lumens (Lm).
Divide rooms of irregular shape into shapes (for example, a square and a triangle), and perform the calculation separately for each.
You can measure the level of illumination at home with a lux meter.
Living space lighting
Lighting in the house is as important as the interior. First of all, they divide the entire space into areas that differ not only in size, but also in functionality.
Namely:
- Hallway– its location implies the absence natural light, so they create something artificial in the hallway. For this purpose, directional lighting devices with wide dispersion angles are used.
- Living room (hall)- a room with many functions. Therefore, maximum functionality is achieved with lighting, combining general with spot lighting.
- Kitchen- an area that has separate work areas, in which spot lighting is added to the general one.
- Bedroom– intended directly for rest and sleep. For bedrooms, soft and warm tones of artificial light are selected. Also, it makes sense for them to adjust the lighting intensity.
- Bathroom– as in previous cases, local lighting is added to the main one.
When choosing a lighting fixture for a bathroom, you need to make sure that this sample has a high degree of protection (IP) from humidity.
Proper lighting in the apartment will help not only emphasize or highlight a certain area, but also erase visual boundaries.
LED lamps for residential premises
Some time ago, LED lighting was considered unacceptable for the home. The main factors were the high price, as well as the brightness and color of the lighting.
But today, such lighting is becoming relatively inexpensive. And the choice in power, design, range and size is simply huge. The only limitation can be your imagination, where and how to use LED lamps. Also, such lamps have a number of advantages.
Advantages:
- Low energy consumption (allows long-term use to quickly recoup the cost of the lamp);
- Durability (if you choose a quality product, the service life is many times longer than that of conventional incandescent, fluorescent and halogen lamps);
- Does not heat up during operation (which increases the possibilities of placement in accordance with the design).
And these are not all indicators. The best option lighting, can be selected by spectrum and brightness (all values are indicated on the product packaging). For your home, choose lamps that provide warm light.
When choosing LED lamps, please pay attention to the manufacturer. The more famous the brand, the better the product.
An important factor is environmental friendliness. LED lamps do not emit UV radiation, and they do not create fluctuations in light output.
If you decide to do good lighting in the house, it is better to choose LED lamps for this.
Illumination standards for office premises: required value
It's not so common to find offices in which Special attention was given to lighting. Usually these are luminous squares with luminescent flickering, built into the ceiling. But light affects both the psychological and emotional state of a person. With proper lighting, you can achieve high employee productivity throughout the day.
The level of illumination in the office is determined by two standards:
- Russian – illumination level (required scale), recommended within 300 – 400 lux (Lx);
- International standard (European standards) – 500 lux (Lx).
Lighting is divided into general (direct and reflected), light from light sources is scattered throughout the entire office area, and local (lighting directly at the workplaces themselves), illumination is carried out by various lighting devices for local lighting (table lamps and lamps).
The placement of lighting fixtures parallel to the windows is the most correct; this ensures that the light from the lamps matches the light from the windows.
Important and individual approach for each workplace in the office, this is due to the difference in lighting needs for each employee. This is influenced by factors such as vision and age.
Children's playground lighting: standards
Modern playgrounds, of course, differ from sports ones, but in terms of their functionality they can be equated to each other. In addition to the usual slides, swings and carousels, many sports equipment are added for the physical development of children. Therefore, competent and effective lighting for children's playgrounds is simply necessary.
With these characteristics, for children playgrounds important parameters need to be taken into account.
List of parameters:
- Ensuring comfort and safety;
- Injury prevention;
- Possibility to be on site in the evening (especially in winter).
The lighting standard for children's playgrounds according to the Russian standard is 10 lux. But as sites are improved, the required (normal) level of illumination should be 70 - 100 lux.
The level of color rendering is of great importance when lighting children's playgrounds. For easy identification of small and moving objects.
In accordance with the size, the optimal ratio of height and location of lighting fixtures is selected for various playgrounds. These include cantilever (up to 10 meters high) and local (up to 4 meters high). The power of a separate street lighting device is calculated according to SNiP standards.
If the site is not sufficiently illuminated, the lighting must be improved by adding lighting fixtures.
It is worth taking into account the aesthetic component by choosing lamps that highlight the exterior of the site.
How many watts are needed to light a room: converting lumens to watts
The questions - how to determine what kind of lighting should be in a separate room or one room, how to convert lux into watts, how to select and calculate the required number of lamps - have fairly simple answers.
Let's do the calculation using an example. We need to illuminate a hall of 20 m2 with a chandelier with five incandescent light bulbs. What power in watts should I choose for lamps?
To calculate you will need:
- Illumination level;
- Area in square meters.
We multiply the illumination rate by square meters. 150 x 20 = 3000. The total luminous flux should be 3000 Lumens. This means that for normal lighting you will need 5 lamps of 60 watts each. If we convert to European standards, we get 4000 lumens.
Due to outdated standards, multiply the illumination rate by 1.5 times.
Do not forget, unlike incandescent lamps, there are several other types of artificial lighting sources that are more reliable and economical.
What are lighting standards (video)
The right light is needed not only at home or in the office. It is necessary for comfortable rest in a hotel, walking down the street, its use in kindergartens and shopping malls is important. The only difference is purpose and functionality. Based on the tests conducted, psychologists have proven that with well-designed lighting, not only the psycho-emotional, but also the general condition of a person improves.
Light has a direct impact on a person's well-being. Insufficient lighting in the workplace can lead to loss of concentration, blurred vision, depressed mental state and low performance. Excessively bright light is irritating to a person and can cause stress. Proper lighting is very important for good performance.
Light level in different types premises is strictly regulated by sanitary rules and regulations. The sanitary and epidemiological service monitors compliance with these standards.
Units of measurement of room illumination
The numerical value of illumination is equal to the luminous flux that falls perpendicular to the plane per unit surface area. If light falls on a plane at an angle, then the illumination value decreases in direct proportion to the cosine of the angle of inclination of the rays.
According to the International System of Units (SI), the level of illumination is measured in lux. One lux is equal to one lumen (a unit of measurement of luminous flux) per 1m2.
In the absolute physical system of units (APS), illumination is measured in photos. One phot is equal to 10,000 lux. Illumination is a value directly proportional to the intensity of light that comes from the light source. The farther an object is from the light source, the less illumination it receives.
In England and America, a slightly different unit of measurement of illumination is traditionally adopted. It is called a foot-candle and means that the light intensity equal to one candela comes from a source located at a distance of one foot from the illuminated surface.
There are several other units of measurement, but all of them are either derived from lux or are outdated and do not correspond to the generally accepted international system. Therefore, their use is undesirable.
How to measure room illumination
In order to determine the level of illumination in a room, special devices are used:
- Luxmeter.
- Light meter and exposure meter;
- Flash meter;
- Photometer.
The main device for measuring the actual illumination of a room in the presence of artificial and natural light sources is a lux meter. It can be used to:
- carry out illumination measurements for the purpose of certification of workplaces;
- control the compliance of the illumination level with sanitary standards in premises for various purposes;
- determine the compliance of illumination indicators with the calculated values during the installation of lighting fixtures;
- identify the level of decrease in the intensity of operation of lighting devices, and make a decision on the need to replace them.
Luxometer for measuring room illumination
The principle of operation of a lux meter is that a stream of light enters the built-in photocell, and a stream of electrons is released inside the semiconductor. As a result, there is electricity, the magnitude of which is directly proportional to the strength of light incident on the photocell. It is this indicator that is reflected on the scale of the device.
Light meter models are divided into two main groups depending on the method of mounting the sensor:
- with a rigidly fixed sensor (in the form of a monoblock);
- with a remote sensor that is connected using a flexible cable.
To carry out the simplest measurements, it is enough to use a regular monoblock luxmeter without any additional functions. For the purpose of conducting professional research, device models with built-in internal memory and a function for determining the average value of readings are used. In addition, it is possible that the lux meter contains additional light filters, which make it possible to more effectively determine the amount of light intensity emitted by lighting devices with different shades colors.
Models with a remote sensor provide the most accurate readings because they are less susceptible to external influences. In modern lux meters, the measurement result is shown on a liquid crystal display.
Exposure meters and exposure meters are used in photographic equipment. They perform the function of determining the brightness and illumination of the exposure. This is necessary to obtain high-quality photographs. Light meters are divided into built-in and external models.
The flash meter measures the level of illumination during photography using flash lighting devices. In modern cameras it is built in advance and automatically adjusts the flash power. Professional photo workshops are equipped with remote flash meters with an indicating system that can measure not only incident, but also reflected light.
A photometer (multimeter) is a more advanced version of a flash meter and combines its functions with the capabilities of an exposure meter.
What is the light pulsation coefficient and its norms?
Any lighting device emits luminous flux not uniformly, but with a certain number of fluctuations. This effect is difficult to notice with the naked eye. But its impact on a person’s well-being is very significant. The invisible influence of light is dangerous because it is not always possible to recognize it. As a result, a person may experience sleep disorders, depression, weakness, internal discomfort, and disturbances in the functioning of the heart.
Lighting pulsation
The lighting pulsation coefficient is an indicator of the depth of changes over time in the light flux falling per unit surface. It is expressed as a percentage. To calculate the coefficient, it is necessary to subtract the minimum value for the same period from the maximum illumination value for a certain period of time, and then divide the resulting result by the average illumination value and multiply by 100%.
Sanitary regulations set a limit on the maximum value of the lighting pulsation coefficient.
In the place where the main work operations are carried out, it should not exceed 20%. The more responsible the work, the lower the indicator should be. For administrative buildings and offices where intense visual work is carried out, a pulsation coefficient of more than 5% is not allowed.
But in this case, the pulsation frequency of the light flux is taken into account only up to 300 Hz, since higher frequencies are not perceived human body and is unable to have any influence on him.
How to measure ripple factor?
To determine the frequency with which the lighting pulsates, use special device– illumination, brightness and lighting pulsation meter. With its help you can find out:
- room illumination level;
- brightness level of devices artificial lighting and monitor screens;
- pulsating waves of light that appear from flickering various types lamps;
- pulsations of illumination of monitors of all varieties.
The operating principle of any luxmeter-brightness-pulsemeter is that a stream of light enters the photosensor, then the signal from it is converted, and the measurement result appears on the liquid crystal display. To determine the pulsation coefficient, it is necessary to analyze the data obtained independently or using a special computer program.
The most popular devices for measuring pulsations are “Ecolight-01”, “Ecolight-02”, “Lupin”. And to analyze the obtained data on a computer, you can use the Ecolight-AP program.
Difference different devices from each other consists of the quality of photocells, their level of sensitivity, the type of battery and other important components.
The highest lighting pulsation coefficient, which even reaches 100%, is observed in. Slightly less pulsating - but they show a small pulsation coefficient (maximum 25%). In this case, the cost and quality of the lighting source does not matter. A high ripple factor can be found even in the most expensive lamps.
Tables of lighting standards for various rooms
For each type of premises, clear standards have been established for minimum illumination levels and maximum permissible lighting pulsation coefficients.
Table 1 - Lighting standards for retail premises
Lighting of the trading floor
Table 2 - Lighting standards for schools
Table 3 – Lighting standards for kindergartens
Table 4 - Lighting standards for residential premises
Table 5 - Lighting standards for medical institutions
| Room type | Illumination level, lux | Maximum value of pulsation coefficient, % |
| Doctors' offices | 500 | 10 |
| Therapists' offices in the clinic | 300 | 15 |
| Dark room in an ophthalmologist's office | 20 | 10 |
| Operating room | 500 | 10 |
| Maternity room | 500 | 10 |
| Functional diagnostic rooms | 300 | 15 |
| X-ray room | 50 | - |
| Fluorography room | 200 | 20 |
| Auxiliary premises | 75 | - |
| Children's wards | 200 | 15 |
| Wards for adult patients | 100 | 15 |
| Laboratories | 500 | 10 |
Table 6 – Illumination standards for a car wash
Great importance is given to controlling the presence of pulsation from lighting sources in office premises, you can read more about this. Lighting standards production premises and workshops set clear values for the minimum number of luxes depending on the characteristics of the production process; all the most important things on this topic can be read.
How to reduce lighting pulsation?
There are several methods on how to reduce excessive lighting pulsation:
- The use of lighting devices that operate on alternating current with a frequency above 400Hz.
- Installation of conventional lamps on various phases of a three-phase network.
- Installation of compensating ballasts in the luminaire and connection of power supply to lamps with a shift (the first lamp is with lagging current, and the second is with leading current).
- Use of lamps with electronic ballasts.
The choice of method by which you can achieve the required indicators of the lighting pulsation coefficient depends on technical specifications in each specific case. In some rooms, all lamps are connected to one phase of the network, so their installation to different phases can be difficult.
Most convenient option there may be a purchase that meets all sanitary standards. Separate installation of electronic ballasts into previously installed lighting fixtures is also possible.
Documents regulating illumination standards and pulsation coefficient
The main document that regulates the standards of illumination of premises of all types and the pulsation coefficient is the Code of Rules SP 52.13330.2011 adopted in 2011. This is a new version of SNIP 23-05-95, which takes into account all the basic requirements of Federal laws on safety and energy efficiency, as well as international standards.
The Code of Practice describes in detail the lighting requirements and the maximum permissible ripple factor in public, industrial and residential premises.
Office lighting standards
It is necessary to control the illumination of the room and the degree of pulsation of artificial light not only for the purpose of passing certification of workplaces or a routine inspection of the sanitary and epidemiological station. Violations of sanitary standards in the field of lighting can lead to serious health problems for everyone who works in this room. And this, in turn, will cause a decline in efficiency and a decrease in the profitability of the enterprise.
In residential buildings, light has no less impact on people. Pulsation invisible to the eye can imperceptibly destroy people's health. Only a responsible approach to the choice of lighting fixtures and computer equipment can prevent all negative consequences.
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