Methods for determining distances without special means

Dangerous radiation from power lines was noticed at the end of the last century. SanPiN standards have been developed, which calculate the minimum safe distance from power lines to a residential building, depending on the size of the voltage in the network. Based on this distance, sanitary zones for power lines were created under high-voltage power lines and the concept of a “burden zone” was introduced - land dangerously close to radiation harmful to health. The sale of residential buildings and plots for individual housing construction and SNT in the sanitary zone of power lines is prohibited.

Near residential buildings

Options for determining distances to objects

Among the useful skills that are recommended to be mastered by everyone who prefers an active holiday to a relaxing holiday is determining the distance on the ground. There are many situations when this skill can be useful - lack of cartographic material or its damage, loss, the need to determine the width of the river by eye, the distance to the target, calculate the height of a tree that needs to be used as a bridge, and more.

There is more than one way to determine distances on the ground

Existing options differ in different measurement errors and instrumentation. You can find out the distance:

1. Using the “by eye” method. Suitable when there are signs of civilization in the area, at least communication poles.
2. Using your own steps. This is a convenient way to calculate the length of a route. Since step length is a constant value, it is recommended to know and remember it in advance.
3. By visibility of objects. Requires skill, gives the most accurate result in clear weather.

Time

Time is the most precious thing we have. But besides philosophy, time also has an important role in mathematics.

Time is the duration of some actions or events.

• For example: from the metro to the house - 10 minutes, from home to the dacha - 2 hours.

The movement time is denoted by the Latin letter t .

The most common units of time you will see are seconds, minutes, and hours.

This formula is useful if you need to find out how long it will take a body to cover a particular distance.

Determining distances “by eye” or by linear objects

The method of measuring distance by eye is suitable when there is an object with a known size (length, width or height). This calculation is considered 90% accurate, and sometimes more if you gain experience.

Linear dimensions of the most common objects:

• passenger car - L*W*H corresponds to 4m*1.5m*1.6m;
• adult – on average 1.7 m;
• human head – H*W corresponds to 0.25m*0.20m;
• communication pole (wooden) – 6 m;
• communication pole (concrete) – 8 m;
• distance between power line poles – 50 m;
• between high-voltage line poles – 100 m;
• village house - 7 m;
• one floor of an apartment building (panel) - 3 m.

LHow to determine the cardinal directions in nature, I tell you in the article: How to determine north and south without a compass, day and night

How to determine the distance to an object

Take a ruler and place it at the level of the object being measured, 50 cm from the eyes. The dimensions of an object (length, width or height) are measured using a ruler and counted in millimeters.

Determining distance using a ruler

Now use the formula:

Distance, m = (actual size in cm/measured size using a ruler in mm)*5.

This academic method has been slightly simplified in the tourist environment. Tourists use their thumb to determine distance.

Let's look at the example of measuring the distance to a communication pole (height 8 m). The length of the thumb is about 6 cm. Stretch your hand in front of you, clench your palm into a fist so that the thumb points up. The distance from the eyes to the finger will be about 60 cm. Determine what length the pillar corresponds to, for example, a third of the finger (2 cm).

Next, it remains to calculate the proportion:

X = (8 m * 60 cm)/2 cm = 240 m.

Health hazards from power lines

However, a voltage of 10 kV is considered safe for humans. It creates a background density not exceeding 10 μT (measured in microtesla). For comparison, the Earth's magnetic field is 30–50 μT.

Prohibited in the security zone of power lines

It differs from the radiation generated by overhead lines in that it has a constant or smoothly varying value. A current with a frequency of 50 Hz passes through the power line - this means that per second the current changes its direction 50 times, a complete oscillation occurs - an alternating current wave. The magnitude of the emitted magnetic field also changes with this frequency.

Note that the highest value of natural vibrations reaches 40 Hz. When constantly in the zone of magnetic waves with high levels, malfunctions occur in the human body. This is possible not only when standing under power lines for a long time, but also next to household electrical appliances, especially thermal ones. The damage caused by the proximity of overhead lines can be compared with the health damage caused by a hairdryer, refrigerator, washing machine or laptop.

In the European Union countries, it is generally accepted that if the voltage in the power line wires is higher than 35 kV and the apartment is located closer than the standard size of the security zone plus 20 m, then, according to the health standards of the United Europe, such proximity can lead to a number of diseases of the nervous and cardiovascular systems .

Standard distances from supports

The distance from power lines and possible harm to health in such a case are absolutely dependent. Construction of housing in the European Union is permitted at a distance of 20 meters from the sanitary protection zone, if we take its value from Russian PUE standards.

All-Russian standards for the distance to residential buildings are stated above in this article.

Below is a table of European standards.

It is necessary to note that the site for individual housing construction or a dacha may partially be closer to the high-voltage line than the minimum distance to the residential building. In the technical passport this strip is indicated as an encumbrance zone. On this land you can plant a vegetable garden, a garden and put up a fence. You cannot build a house and construct outbuildings. A seating area in the yard should be located away from power lines.

Calculating distance in steps

The ability to determine distances with your own steps can be useful both for lovers of tourism (for example, when drawing up maps of the area and vice versa, when searching for an object indicated on a map or plan), and for ordinary citizens who engage in, say, race walking.

Step length is a constant value

Steps are used as a measuring unit because a person usually takes steps of equal length when walking at a measured pace on a flat surface. It is this length of your step that is recommended to be calculated and remembered as a reference.

The change in reference length is affected by:

• human fatigue
• air temperature, in hot weather steps are shorter and movement speed is lower,
• cross-country movement,
• walking in a group, when we intuitively or intentionally adapt to the speed and pace of other people,
• heavy backpack.

“Wet feet” method There are several ways to determine step length.

1. Method "Wet feet"
   The point of this measurement is that you need to “mark” with wet feet, then take a tape measure and find out the distance from one heel to the other. For the purity of calculations, you should take several steps, measure the distances and calculate the average value.

   Any puddle is suitable for the method, if there is dry asphalt nearby, you can walk through snow, mud, sandy beach, specially wet your feet and walk on the floor at home. The main thing is that there are footprints left.

2. Method of walking for a short distance Measure a distance of 10 meters on a flat surface with a tape measure. After that, walk and count the number of steps. Divide 10 meters into steps to get the length of one step. Then walk in the opposite direction and calculate your step length again. Calculate the average step value.
3. By map For this method, a map, a diagram of the area with objects A and B, located in relative proximity to each other and the distance between which is easy to calculate, is suitable. Go from point A to point B and count your steps. Divide the distance by the resulting amount - you will find out the length of your own step. Instead of a paper map, you can use a navigator to plot a route between two points and then follow it.
4. Based on height Knowing your height, you can also calculate your step length, but the calculation will be too average. To do this, height expressed in centimeters must be multiplied by 0.413 (for women) or 0.415 (for men).

Having a step length, you can now easily calculate distances on a hike or walk. It’s interesting that if you make this kind of counting a habit, you’ll soon notice that you’re counting your steps out of inertia. There are two ways to count steps.

1. Make every step count.
2. Count every step, i.e. only the right leg or only the left. This is a more convenient option for long journeys.

In order not to get lost when counting, when the number of steps exceeds 100, you can bend your finger for every hundred or transfer matches from one pocket to another.

Visibility of objects - as a way to find out distance

By the fact that objects are distinguishable whether they are far away with the eye or not, it is also possible to determine the distance quite accurately. With training, it is possible to reduce the error in determining the length to 10-20% per 1 km.

Determining distance by visible objects

Using this method, you need to take into account that the eye perceives distances differently:

• at night, the distance visually increases;
• in the presence of precipitation, the object will appear further away;
• an object on a plain appears closer than on a hilly area;
• water barriers greatly reduce distances;
• a dark object will appear further away than a light object.

The data below is designed to determine the distance to an object during the day in clear weather on flat terrain.

1. If your eye could discern a village house in the distance, then the distance to it is no more than 5 km. Are you able to see the pipe on the roof? It's already 3 km.
2. If it is possible to see the movement of a person’s legs (walking or running) – up to 700 m.
3. Tree trunks and communication line poles can be recognized from a distance of no more than 1 km.
4. The face is visible from a distance of up to 100 m.

LHow to determine the weather in hiking conditions, you will learn from the article: Ways to find out the weather by signs for tomorrow

Cheapness of land plots in the sanitary zone

Based on SanPiN norms, construction rules were determined and security zones were created under high-voltage lines. Any children's institutions, including educational ones, located at a dangerous distance, must be closed. It was prohibited to build residential buildings for permanent and temporary residence closer than the minimum distance to high-voltage lines specified in SanPiN 2971-84.

At the power plant

Please note that it is not possible to sell a house located in a dangerous zone. No sanitary or fire safety organizations will approve such a document. When developing land plots of individual housing construction, it is necessary to take into account the distance to the power line located nearby.

Land prices show how dangerous the radiation from high-voltage lines is for human health. You can notice that the cost of land near power lines is low. As you move away from it, it rises every 30 meters. You shouldn't be foolishly tempted by a cheap price. First of all, you need to think about the health of your family.