- The unit of measurement of pressure in SI is pascal (Russian designation: Pa; international: Pa) = N/m 2
- Conversion table for pressure measurement units. Pa; MPa; bar; atm; mmHg.; mm H.S.; m w.st., kg/cm 2 ; psf; psi; inches Hg; inches in.st. below
- Note, there are 2 tables and a list. Here's another useful link:
| In units: | ||||||||
| Pa (N/m2) | MPa | bar | atmosphere | mmHg Art. | mm in.st. | m in.st. | kgf/cm 2 | |
| Should be multiplied by: | ||||||||
| Pa (N/m2) - pascal, SI unit of pressure | 1 | 1*10 -6 | 10 -5 | 9.87*10 -6 | 0.0075 | 0.1 | 10 -4 | 1.02*10 -5 |
| MPa, megapascal | 1*10 6 | 1 | 10 | 9.87 | 7.5*10 3 | 10 5 | 10 2 | 10.2 |
| bar | 10 5 | 10 -1 | 1 | 0.987 | 750 | 1.0197*10 4 | 10.197 | 1.0197 |
| atm, atmosphere | 1.01*10 5 | 1.01* 10 -1 | 1.013 | 1 | 759.9 | 10332 | 10.332 | 1.03 |
| mmHg Art., mm mercury | 133.3 | 133.3*10 -6 | 1.33*10 -3 | 1.32*10 -3 | 1 | 13.3 | 0.013 | 1.36*10 -3 |
| mm w.c., mm water column | 10 | 10 -5 | 0.000097 | 9.87*10 -5 | 0.075 | 1 | 0.001 | 1.02*10 -4 |
| m w.st., meter of water column | 10 4 | 10 -2 | 0.097 | 9.87*10 -2 | 75 | 1000 | 1 | 0.102 |
| kgf/cm 2, kilogram-force per square centimeter | 9.8*10 4 | 9.8*10 -2 | 0.98 | 0.97 | 735 | 10000 | 10 | 1 |
| 47.8 | 4.78*10 -5 | 4.78*10 -4 | 4.72*10 -4 | 0.36 | 4.78 | 4.78 10 -3 | 4.88*10 -4 | |
| 6894.76 | 6.89476*10 -3 | 0.069 | 0.068 | 51.7 | 689.7 | 0.690 | 0.07 | |
| Inches Hg / inches Hg | 3377 | 3.377*10 -3 | 0.0338 | 0.033 | 25.33 | 337.7 | 0.337 | 0.034 |
| Inches in.st. / inchesH2O | 248.8 | 2.488*10 -2 | 2.49*10 -3 | 2.46*10 -3 | 1.87 | 24.88 | 0.0249 | 0.0025 |
| To convert pressure in units: | In units: | |||
| psi pound square feet (psf) | psi inch / pound square inches (psi) | Inches Hg / inches Hg | Inches in.st. / inchesH2O | |
| Should be multiplied by: | ||||
| Pa (N/m 2) - SI unit of pressure | 0.021 | 1.450326*10 -4 | 2.96*10 -4 | 4.02*10 -3 |
| MPa | 2.1*10 4 | 1.450326*10 2 | 2.96*10 2 | 4.02*10 3 |
| bar | 2090 | 14.50 | 29.61 | 402 |
| atm | 2117.5 | 14.69 | 29.92 | 407 |
| mmHg Art. | 2.79 | 0.019 | 0.039 | 0.54 |
| mm in.st. | 0.209 | 1.45*10 -3 | 2.96*10 -3 | 0.04 |
| m in.st. | 209 | 1.45 | 2.96 | 40.2 |
| kgf/cm 2 | 2049 | 14.21 | 29.03 | 394 |
| psi pound square feet (psf) | 1 | 0.0069 | 0.014 | 0.19 |
| psi inch / pound square inches (psi) | 144 | 1 | 2.04 | 27.7 |
| Inches Hg / inches Hg | 70.6 | 0.49 | 1 | 13.57 |
| Inches in.st. / inchesH2O | 5.2 | 0.036 | 0.074 | 1 |
Detailed list of pressure units, one pascal is:
- 1 Pa (N/m 2) = 0.0000102 Atmosphere (metric)
- 1 Pa (N/m2) = 0.0000099 Atmosphere (standard) = Standard atmosphere
- 1 Pa (N/m2) = 0.00001 Bar / Bar
- 1 Pa (N/m 2) = 10 Barad / Barad
- 1 Pa (N/m2) = 0.0007501 Centimeters Hg. Art. (0°C)
- 1 Pa (N/m2) = 0.0101974 Centimeters in. Art. (4°C)
- 1 Pa (N/m2) = 10 Dyne/square centimeter
- 1 Pa (N/m2) = 0.0003346 Foot of water (4 °C)
- 1 Pa (N/m2) = 10 -9 Gigapascals
- 1 Pa (N/m2) = 0.01
- 1 Pa (N/m2) = 0.0002953 Dumov Hg. / Inch of mercury (0 °C)
- 1 Pa (N/m2) = 0.0002961 InchHg. Art. / Inch of mercury (15.56 °C)
- 1 Pa (N/m2) = 0.0040186 Dumov v.st. / Inch of water (15.56 °C)
- 1 Pa (N/m 2) = 0.0040147 Dumov v.st. / Inch of water (4 °C)
- 1 Pa (N/m 2) = 0.0000102 kgf/cm 2 / Kilogram force/centimetre 2
- 1 Pa (N/m 2) = 0.0010197 kgf/dm 2 / Kilogram force/decimetre 2
- 1 Pa (N/m2) = 0.101972 kgf/m2 / Kilogram force/meter 2
- 1 Pa (N/m 2) = 10 -7 kgf/mm 2 / Kilogram force/millimeter 2
- 1 Pa (N/m 2) = 10 -3 kPa
- 1 Pa (N/m2) = 10 -7 Kilopound force/square inch
- 1 Pa (N/m 2) = 10 -6 MPa
- 1 Pa (N/m2) = 0.000102 Meters w.st. / Meter of water (4 °C)
- 1 Pa (N/m2) = 10 Microbar / Microbar (barye, barrie)
- 1 Pa (N/m2) = 7.50062 Microns Hg. / Micron of mercury (millitorr)
- 1 Pa (N/m2) = 0.01 Millibar / Millibar
- 1 Pa (N/m2) = 0.0075006 (0 °C)
- 1 Pa (N/m2) = 0.10207 Millimeters w.st. / Millimeter of water (15.56 °C)
- 1 Pa (N/m2) = 0.10197 Millimeters w.st. / Millimeter of water (4 °C)
- 1 Pa (N/m 2) = 7.5006 Millitorr / Millitorr
- 1 Pa (N/m2) = 1N/m2 / Newton/square meter
- 1 Pa (N/m2) = 32.1507 Daily ounces/sq. inch / Ounce force (avdp)/square inch
- 1 Pa (N/m2) = 0.0208854 Pounds of force per square meter. ft / Pound force/square foot
- 1 Pa (N/m2) = 0.000145 Pounds of force per square meter. inch / Pound force/square inch
- 1 Pa (N/m2) = 0.671969 Poundals per sq. ft / Poundal/square foot
- 1 Pa (N/m2) = 0.0046665 Poundals per sq. inch / Poundal/square inch
- 1 Pa (N/m2) = 0.0000093 Long tons per square meter. ft / Ton (long)/foot 2
- 1 Pa (N/m2) = 10 -7 Long tons per square meter. inch / Ton (long)/inch 2
- 1 Pa (N/m2) = 0.0000104 Short tons per square meter. ft / Ton (short)/foot 2
- 1 Pa (N/m2) = 10 -7 Tons per sq. inch / Ton/inch 2
- 1 Pa (N/m2) = 0.0075006 Torr / Torr
- pressure in pascals and atmospheres, convert pressure to pascals
- Atmosphere pressure equal to XXX mmHg. express it in pascals
- gas pressure units - translation
- fluid pressure units - translation
We are taught about what atmospheric pressure is at school during natural history and geography lessons. We get acquainted with this information and safely throw it out of our heads, rightly believing that we will never be able to use it.
But years later, stress and environmental conditions environment will have a sufficient impact on us. And the concept of “geodependence” will no longer seem nonsense, since pressure surges and headache will begin to poison life. At this moment you will have to remember what it is like in Moscow, for example, in order to adapt to new conditions. And move on with your life.
School basics
The atmosphere that surrounds our planet, unfortunately, literally puts pressure on all living and nonliving things. There is a term to define this phenomenon - atmospheric pressure. This is the force of the air column acting on the area. In the SI system we talk about kilograms per square centimeter. Normal atmospheric pressure (optimal indicators for Moscow have long been known) affects the human body with the same force as a weight weighing 1.033 kg. But most of us don't notice this. There are enough gases dissolved in body fluids to neutralize all unpleasant sensations.
Atmospheric pressure standards vary in different regions. But 760 mmHg is considered ideal. Art. Experiments with mercury turned out to be the most revealing at a time when scientists were proving that air has weight. Mercury barometers are the most common devices for determining pressure. It should also be remembered that ideal conditions, for which the mentioned 760 mm Hg are relevant. Art., is a temperature of 0 ° C and the 45th parallel.
IN international system units are used to define pressure in Pascals. But for us, the use of mercury column fluctuations is more familiar and understandable.
Relief features
Of course, many factors influence the value of atmospheric pressure. The most significant are the relief and proximity to the magnetic poles of the planet. The norm of atmospheric pressure in Moscow is fundamentally different from the indicators in St. Petersburg; and for residents of some remote village in the mountains, this figure may seem completely abnormal. Already at 1 km above sea level it corresponds to 734 mm Hg. Art.
As already noted, in the region of the earth’s poles the amplitude of pressure changes is much higher than in the equatorial zone. Even during the day, the atmospheric pressure changes slightly. Insignificantly, however, only by 1-2 mm. This is due to the difference between day and night temperatures. At night it is usually cooler, which means the pressure is higher.
Pressure and man
For a person, in essence, it does not matter what atmospheric pressure is: normal, low or high. These are very conditional definitions. People tend to get used to everything and adapt. The dynamics and magnitude of changes in atmospheric pressure are much more important. On the territory of the CIS countries, in particular in Russia, there are quite a lot of zones. Often, local residents do not even know about it.
The norm of atmospheric pressure in Moscow, for example, may well be considered as a variable value. After all, every skyscraper is a kind of mountain, and the higher and faster you go up (or go down), the more noticeable the difference will be. Some people may well pass out while riding a high-speed elevator.
Adaptation
Doctors almost unanimously agree that the question “what atmospheric pressure is considered normal” (is it Moscow or any locality planets - not the point) is incorrect in itself. Our body adapts perfectly to life above or below sea level. And if the pressure does not have a detrimental effect on a person, it can be considered normal for the area. Doctors say that the normal atmospheric pressure in Moscow and other large cities is in the range from 750 to 765 mm Hg. pillar
The pressure drop is a completely different matter. If within a few hours it rises (falls) by 5-6 mm, people begin to experience discomfort and pain. This is especially dangerous for the heart. Its beating becomes more frequent, and a change in the frequency of breaths leads to a change in the rhythm of oxygen supply to the body. The most common ailments in such a situation are weakness, etc.
Meteor dependence
Normal atmospheric pressure for Moscow may seem like a nightmare to a visitor from the North or the Urals. After all, each region has its own norm and, accordingly, its own understanding of the stable state of the body. And since in life we don't concentrate on exact indicators pressure, forecasters always focus on whether the pressure is high or low for a given region.
After all, not every person can boast that they do not notice the corresponding changes. Anyone who cannot call himself lucky in this matter must systematize his feelings during pressure changes and find acceptable countermeasures. Often a cup of strong coffee or tea is enough, but sometimes more serious help in the form of medication is needed.
Pressure in the metropolis
Residents of megacities are the most weather-dependent. It is here that a person experiences more stress, lives life at a high pace and experiences environmental degradation. Therefore, knowing what the normal atmospheric pressure is for Moscow is vital.
The capital of the Russian Federation is located on the Central Russian Upland, which means that there is a priori a zone of low pressure. Why? It's very simple: the higher you are above sea level, the lower the atmospheric pressure. For example, on the banks of the Moscow River this figure will be 168 m. And the maximum value in the city was recorded in Teply Stan - 255 m above sea level.
It is quite possible to assume that Muscovites will experience abnormally low atmospheric pressure much less frequently than residents of other regions, which, of course, cannot but make them happy. And yet, what atmospheric pressure is considered normal in Moscow? Meteorologists say that it usually does not exceed 748 mm Hg. pillar This means little, since we already know that even a quick ride in an elevator can have a significant impact on a person's heart.
On the other hand, Muscovites do not feel any discomfort if the pressure fluctuates between 745-755 mm Hg. Art.
Danger
But from the point of view of doctors, not everything is so optimistic for the residents of the metropolis. Many experts quite reasonably believe that by working on the upper floors of business centers, people expose themselves to danger. Indeed, in addition to the fact that they live in a zone of low pressure, they also spend almost a third of the day in places with
If we add to this fact violations of the building ventilation system and permanent job air conditioners, it becomes obvious that the employees of such offices are the most incapacitated, sleepy and sick.
Results
Actually, there are a few things to remember. Firstly, there is no single ideal value for normal atmospheric pressure. There are regional standards that can vary significantly in absolute terms. Secondly, features human body make it easy to experience pressure changes if they happen rather slowly. Thirdly, the more healthy image life we lead and the more often we manage to maintain a daily routine (getting up at the same time, long night sleep, following a basic diet, etc.), the less we are susceptible to weather dependence. This means they are more energetic and cheerful.
The air surrounding the Earth has mass, and despite the fact that the mass of the atmosphere is about a million times less than the mass of the Earth ( total weight atmosphere is 5.2 * 10 21 g, and 1 m 3 of air at the earth's surface weighs 1.033 kg), this mass of air exerts pressure on all objects located on the earth's surface. The force with which air presses on the earth's surface is called atmospheric pressure.
A column of air weighing 15 tons presses on each of us. Such pressure can crush all living things. Why don't we feel it? This is explained by the fact that the pressure inside our body is equal to atmospheric pressure.
In this way, internal and external pressures are balanced.
Barometer
Atmospheric pressure is measured in millimeters of mercury (mmHg). To determine it, they use a special device - a barometer (from the Greek baros - heaviness, weight and metreo - I measure). There are mercury and liquid-free barometers.
Liquidless barometers are called aneroid barometers(from the Greek a - negative particle, nerys - water, i.e. acting without the help of liquid) (Fig. 1).
Rice. 1. Aneroid barometer: 1 — metal box; 2 - spring; 3 - transmission mechanism; 4 — pointer arrow; 5 - scale
Normal atmospheric pressure
Normal atmospheric pressure is conventionally taken to be air pressure at sea level at a latitude of 45° and at a temperature of 0 °C. In this case, the atmosphere presses on every 1 cm 2 of the earth's surface with a force of 1.033 kg, and the mass of this air is balanced mercury column height 760 mm.
Torricelli experience
The value of 760 mm was first obtained in 1644. Evangelista Torricelli(1608-1647) and Vincenzo Viviani(1622-1703) - students of the brilliant Italian scientist Galileo Galilei.
E. Torricelli sealed a long glass tube with divisions at one end, filled it with mercury and lowered it into a cup of mercury (this is how the first mercury barometer was invented, which was called the Torricelli tube). The mercury level in the tube dropped as some of the mercury spilled into the cup and settled at 760 millimeters. A void formed above the column of mercury, which was called Torricelli's void(Fig. 2).
E. Torricelli believed that the atmospheric pressure on the surface of the mercury in the cup is balanced by the weight of the mercury column in the tube. The height of this column above sea level is 760 mm Hg. Art.
Rice. 2. Torricelli experience
1 Pa = 10 -5 bar; 1 bar = 0.98 atm.
High and low atmospheric pressure
Air pressure on our planet can vary widely. If the air pressure is more than 760 mm Hg. Art., then it is considered elevated, less - reduced.
Since the air becomes more and more rarefied as it rises upward, the atmospheric pressure decreases (in the troposphere on average 1 mm for every 10.5 m of rise). Therefore, for territories located on different heights above sea level, the average will be its value of atmospheric pressure. For example, Moscow lies at an altitude of 120 m above sea level, so its average atmospheric pressure is 748 mm Hg. Art.
Atmospheric pressure rises twice during the day (morning and evening) and decreases twice (after noon and after midnight). These changes are due to the change and movement of air. During the year on the continents, the maximum pressure is observed in winter, when the air is supercooled and compacted, and the minimum pressure is observed in summer.
The distribution of atmospheric pressure over the earth's surface has a pronounced zonal character. This is due to uneven heating of the earth's surface, and consequently, changes in pressure.
On the globe there are three zones with a predominance of low atmospheric pressure (minimums) and four zones with a predominance of high atmospheric pressure (maxima).
At equatorial latitudes, the Earth's surface warms up greatly. Heated air expands, becomes lighter and therefore rises. As a result, low atmospheric pressure is established near the earth's surface near the equator.
At the poles, under the influence of low temperatures, the air becomes heavier and sinks. Therefore, at the poles the atmospheric pressure is increased by 60-65° compared to the latitudes.
In the high layers of the atmosphere, on the contrary, over hot areas the pressure is high (although lower than at the Earth's surface), and over cold areas it is low.
General scheme The distribution of atmospheric pressure is as follows (Fig. 3): along the equator there is a belt of low pressure; at 30-40° latitude of both hemispheres - belt high pressure; 60-70° latitude - low pressure zones; in the polar regions there are areas of high pressure.
As a result of the fact that in the temperate latitudes of the Northern Hemisphere in winter the atmospheric pressure over the continents increases greatly, the low pressure belt is interrupted. It persists only over the oceans in the form of closed areas of low pressure - the Icelandic and Aleutian lows. On the contrary, winter maximums form over the continents: Asian and North American.
Rice. 3. General diagram of atmospheric pressure distribution
In summer, in the temperate latitudes of the Northern Hemisphere, the belt of low atmospheric pressure is restored. A huge area of low atmospheric pressure centered in tropical latitudes—the Asian Low—forms over Asia.
In tropical latitudes, the continents are always warmer than the oceans, and the pressure above them is lower. Thus, there are maxima over the oceans throughout the year: North Atlantic (Azores), North Pacific, South Atlantic, South Pacific and South Indian.
The lines that connect points with the same atmospheric pressure on a climate map are called isobars(from the Greek isos - equal and baros - heaviness, weight).
The closer the isobars are to each other, the faster the atmospheric pressure changes over a distance. The amount of change in atmospheric pressure per unit distance (100 km) is called pressure gradient.
The formation of atmospheric pressure belts near the earth's surface is influenced by the uneven distribution of solar heat and the rotation of the Earth. Depending on the time of year, both hemispheres of the Earth are heated by the Sun differently. This causes some movement of the atmospheric pressure belts: in summer - to the north, in winter - to the south.
In which the pressure is balanced by a column of liquid. It is often used as a liquid because it has a very high density (≈13,600 kg/m³) and low saturated vapor pressure at room temperature.
Atmospheric pressure at sea level is approximately 760 mmHg. Art. Standard atmospheric pressure is taken to be (exactly) 760 mmHg. Art. , or 101,325 Pa, hence the definition of a millimeter of mercury (101,325/760 Pa). Previously, a slightly different definition was used: the pressure of a column of mercury with a height of 1 mm and a density of 13.5951·10 3 kg/m³ with a free fall acceleration of 9.806 65 m/s². The difference between these two definitions is 0.000014%.
Millimeters of mercury are used, for example, in vacuum technology, in weather reports and in measuring blood pressure. Since in vacuum technology very often pressure is measured simply in millimeters, omitting the words “mercury column”, the natural transition for vacuum engineers to microns (microns) is carried out, as a rule, also without indicating “mercury column pressure”. Accordingly, when a pressure of 25 microns is indicated on a vacuum pump, we are talking about the maximum vacuum created by this pump, measured in microns of mercury. Of course, no one uses a Torricelli pressure gauge to measure such low pressures. To measure low pressures, other instruments are used, for example, McLeod pressure gauge (vacuum gauge).
Sometimes millimeters of water column are used ( 1 mmHg Art. = 13,5951 mm water Art. ). In the USA and Canada, the unit of measurement “inch of mercury” (designation - inHg) is also used. 1 inHg = 3,386389 kPa at 0 °C.
| Pascal (Pa, Pa) |
Bar (bar, bar) |
Technical atmosphere (at, at) |
Physical atmosphere (atm, atm) |
Millimeter of mercury (mm Hg, mmHg, Torr, torr) |
Water column meter (m water column, m H 2 O) |
Pound-force per sq. inch (psi) |
|
|---|---|---|---|---|---|---|---|
| 1 Pa | 1 / 2 | 10 −5 | 10.197 10 −6 | 9.8692 10 −6 | 7.5006 10 −3 | 1.0197 10 −4 | 145.04 10 −6 |
| 1 bar | 10 5 | 1 10 6 din / cm 2 | 1,0197 | 0,98692 | 750,06 | 10,197 | 14,504 |
| 1 at | 98066,5 | 0,980665 | 1 kgf/cm 2 | 0,96784 | 735,56 | 10 | 14,223 |
| 1 atm | 101325 | 1,01325 | 1,033 | 1 atm | 760 | 10,33 | 14,696 |
| 1 mmHg | 133,322 | 1.3332·10 −3 | 1.3595 10 −3 | 1.3158 10 −3 | 1 mmHg. | 13.595 10 −3 | 19.337 10 −3 |
| 1 m water Art. | 9806,65 | 9.80665 10 −2 | 0,1 | 0,096784 | 73,556 | 1 m water Art. | 1,4223 |
| 1 psi | 6894,76 | 68.948 10 −3 | 70.307 10 −3 | 68.046 10 −3 | 51,715 | 0,70307 | 1 lbf/in 2 |
see also
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See what “Millimeter of mercury” is in other dictionaries:
- (mm Hg, mm Hg), non-system units. pressure; 1 mmHg art. = 133.332 Pa = 1.35952 10 3 kgf/cm2 = 13.595 mm water. Art. Physical encyclopedic dictionary. M.: Soviet encyclopedia. Chief Editor A. M. Prokhorov. 1983. MILLIME... Physical encyclopedia
Non-system units pressure, app. when measuring atm. water vapor pressure, high vacuum, etc. Designation: Russian. - mmHg art., int. — mm Hg. 1 mmHg Art. equal to hydrostatic pressure of a column of mercury with a height of 1 mm and a density of 13.5951... ... Technical Translator's Guide
- – non-system units. pressure; 1 mmHg art. = 133.332 Pa = 1.35952 10 3 kgf/cm2 = 13.595 mm water. Art. [Physical encyclopedia. In 5 volumes. M.: Soviet Encyclopedia. Editor-in-chief A. M. Prokhorov. 1988.] Term heading: General terms... ... Encyclopedia of terms, definitions and explanations of building materials
Off-system unit of pressure; designation: mmHg Art. 1 mmHg Art. = 133.322 Pa = 13.5951 mm water column. * * * MILLIMETER OF MERCURY COLUMN MILLIMETER OF MERCURY, non-systemic unit of pressure; designation: mmHg Art. 1 mmHg Art. = 133.322... encyclopedic Dictionary
Torr, an off-system unit of pressure used when measuring atmospheric pressure of water vapor, high vacuum, etc. Designation: Russian mm Hg. Art., international mm Hg. 1 mm of mercury is equal to hydrostatic... Encyclopedic Dictionary of Metallurgy
- (mmHg) unit of pressure, as a result of which mercury in the column rises by 1 millimeter. 1 mmHg Art. = 133.3224 Pa... Dictionary in medicine
Torr, a non-systemic unit of pressure used in measurements of atmospheric pressure, partial pressure of water vapor, high vacuum, etc. Designations: Russian mm Hg. Art., international mm Hg. 1 mmHg see equal... ... Great Soviet Encyclopedia
Non-system units not subject to use. pressure. Designation mm Hg. Art. 1 mmHg Art. = 133.322 Pa (see Pascal) ... Big Encyclopedic Polytechnic Dictionary
Off-system unit of pressure; designation: mmHg Art. 1 mmHg Art. = 133.322 Pa = 13.5951 mm water. st... Natural science. encyclopedic Dictionary
About a third of our planet's population reacts sensitively to environmental changes. Most of all, a person’s well-being is influenced by atmospheric pressure - the attraction of air masses to the Earth. What atmospheric pressure is considered normal for a person depends on the area in which he spends the vast majority of the time. Everyone will find their familiar conditions comfortable.
What is atmospheric pressure
The planet is surrounded by an air mass, which, under the influence of gravity, presses on any object, including the human body. The force is called atmospheric pressure. For each square meter crushes a column of air weighing approximately 100,000 kg. Atmospheric pressure is measured using a special device - a barometer. It is measured in pascals, millimeters of mercury, millibars, hectopascals, atmospheres.
The normal atmospheric pressure is 760 mm Hg. Art., or 101 325 Pa. The discovery of the phenomenon belongs to famous physicist Blaise Pascal. The scientist formulated a law: at the same distance from the center of the earth (it doesn’t matter, in the air, at the bottom of a reservoir), the absolute pressure will be the same. He was the first to propose measuring heights using the barometric alignment method.
Atmospheric pressure standards by region
It is impossible to find out what atmospheric pressure is considered normal for a healthy person - there is no definite answer. By different regions globe the impact is not the same. Within relatively small area this value can vary markedly. For example, in Central Asia Slightly elevated numbers are considered standard (on average 715-730 mm Hg). For middle zone In Russia, normal atmospheric pressure is 730-770 mm Hg. Art.
Indicators are related to the elevation of the surface above sea level, wind direction, humidity and ambient temperature. Warm air weighs less than cold. Above the area with elevated temperature or humidity, the compression of the atmosphere is always less. People living in high mountain areas are not sensitive to such barometer readings. Their body was formed under these conditions, and all organs underwent appropriate adaptation.
How pressure affects people
The ideal value is 760 mmHg. Art. What awaits when the mercury column fluctuates:
- A change in optimal indicators (up to 10 mm/h) already leads to a deterioration in well-being.
- With a sharp increase or decrease (on average by 1 mm/h), even healthy people experience a significant deterioration in well-being. Headache, nausea, and loss of performance appear.
Meteor dependence
A person’s sensitivity to weather conditions – wind changes, geomagnetic storms – is called weather dependence. The influence of atmospheric pressure has not yet been fully studied. It is known that when weather conditions change, internal tension is created inside the vessels and cavities of the body. Meteorological dependence can be expressed:
- irritability;
- pain of various localization;
- exacerbation of chronic diseases;
- general deterioration of health;
- problems with blood vessels.
In most cases, people with the following diseases suffer from weather dependence:
- respiratory tract diseases;
- hypo- and hypertension.
Reaction to high blood pressure
A decrease in barometer readings by at least 10 units (770 mm Hg and below) has Negative influence to your health. People with long-standing cardiovascular and cardiovascular diseases are especially affected by weather changes. digestive system. Doctors on such days recommend reducing physical exercise, spend less time on the street, do not abuse heavy food and alcohol. Among the main reactions:
- feeling of congestion in the ear canals;
- decrease in the number of leukocytes in the blood;
- decreased activity of intestinal motility;
- dysfunction of the cardiovascular system;
- poor ability to concentrate.
Reaction to low atmospheric pressure
A decrease in atmospheric compression to 740 mm or less causes opposite shifts in the body. The basis of all unfavorable changes is oxygen starvation. A rarefied air is created, a low percentage of oxygen molecules: it becomes harder to breathe. They arise.
