Minimum ice thickness for humans. Freeze-up is a special period in nature

As soon as the reservoirs are covered with a crust of ice, a whole army of winter extreme connoisseurs immediately appears - fishermen, tourists, those who like to slide down the mountainous river bank on a sled, or those who want to turn part of the river or pond into an ice skating rink. Motorists are also on the alert, finally they don’t have to get to the nearest bridge or crossing, because there is an ice road! Residents of lake and river areas arrange pedestrian and automobile crossings to shorten the path to their destination.

How can you determine whether it is safe to walk, drive, or skate on ice? You should not take risks, endangering yourself and your comrades: for each of these cases there are special rules. If you have children, be sure to teach them what thickness of first ice is safe. It is easier to prevent an accident than to save someone who is caught on fragile ice!

For man

Experienced hunters and fishermen can recognize the approximate thickness of ice by its color. Blueish or “green” ice is considered durable, and the more transparent the ice covering, the stronger it is. A matte white or yellowish color indicates unreliability. If you see a section of a river under ice with no traces of animals or humans, think about why this is. Most likely this is the place where the springs flow; the ice crust there is very thin, and because of the snow it is not visible.

Safe Ice Thickness

This you need to know:

1. Ice that is at least 10 cm thick in fresh water and 15 cm in salt water is considered safe for humans.
2. At river mouths and channels, the ice strength is weakened.
3. Ice is fragile in places of fast currents, gushing springs and runoff water, as well as in areas where aquatic vegetation grows, near trees, bushes, and reeds.
4. If the air temperature remains above 0 degrees for more than three days, then the ice strength decreases by 25%.

Let's consolidate the material about the strength of ice:

• blue ice is durable,
• white - its strength is 2 times less,
• dull white or with a yellowish tint - unreliable.

Don't take winter walks lightly and don't prepare in advance. It is very difficult for someone who has fallen through the ice to get out, since the edges of the hole will break off under its weight. An adult or child can drown from hypothermia, which sets in after a quarter of an hour. Some people experience cold shock.

We recommend that you read the article: Thin ice and its dangers.

Minimum ice thickness for pedestrian crossing

You can download a memo about safety and rules of behavior on ice after the article.

Ice formation process

In early November, reservoirs and rivers begin to become covered with a thin ice crust. When exposed to cold, water crystallizes and creates a surface layer. Ice that can support the weight of a person is formed by the end of November - early December. But sometimes, due to the warm autumn, the ice crust begins to form only in December.

Early appearance of ice is possible only on those reservoirs that are located in northern latitudes. And already at the end of December you can safely move along it not only on foot, but also in other ways.

By this time, its thickness increases, and it can even support a car. The process of forming an ice layer:

• The surface of the required thickness is formed after the formation of the primary layer.
• First, water crystallizes, then ice lard forms.
• Ice lard gains mass and forms snow fields, after which ice cover begins to form.
• At this stage, loose and fragile ice of a pancake shape appears, in the form of ice floes that float separately.
• Then an ice crust appears. But usually its thickness does not exceed 5 cm, so it is unable to withstand the weight of the fisherman.
• The formed thin layer is slightly stronger than the rest. After it, a young layer appears - gray in color. When prolonged frosts set in, it gradually brightens and becomes white. This thickness is suitable for fishing.

The fishing season is open.

For winter crossing

We present the data in the table below.

Safe thickness, m		Taking into account weight, t	Taking into account the distance to the ice edge, m
where there is fresh water	where there is sea water
0,10	0,15	up to 0.1	5
0,20	0,25	up to 0.8	10
0,25	0,30	up to 3.0	20
0,35	0,45	up to 6.5	25
0,40	0,50	to 10	26

Knowing the weight of the equipment, it is not difficult to calculate what the ice should be like.

For technology

Safe thickness, m		Taking into account weight, t	Taking into account the distance to the ice edge, m
where there is fresh water	where there is sea water
0,70	0,55	up to 20	30
100	0,95	up to 40	40

When organizing a crossing for equipment, the following factors are taken into account:

• depth of the reservoir;
• current speed;
• the distance between the banks of the river;
• intensity of cargo traffic;
• when a hydroelectric power station is located nearby, the route calculation data is compared with the operating mode of the hydroelectric power station.

Ice crossing by car

How to identify dangerous areas of ice

To safely move around a body of water, every person needs to know how to determine the thickness of the ice. The thinnest ice forms in places where springs beat, strong undercurrents, under bridges, near swampy shores, in thickets of reeds, reeds, near industrial discharges of hot and warm water, as well as in open spaces.

Places with vegetation, various objects, and piles sticking out of the water are also dangerous, since the ice here is always thinner.

There is no need to rush to move towards the center of the reservoir in order to exclude the possibility of falling into the wormwood. First you need to try the shallow water. If the surface of the reservoir is not covered with snow, then you can observe how radial cracks form under your feet while walking, diverging in different directions.

It is better not to walk on such areas, especially if ring cracks are added; this means that the ice can break at any time.

How to get out if you fall through the ice

Some move across the ice on skis, testing the strength with blows from sticks. If a dark spot has formed on the flat snow cover, then it is better to get around it, not moving too fast, because the ice in this place is thin. Otherwise, when skiing by inertia, you can end up in a hole, even if the fisherman has already seen it.

Theory and practice

The ice track is cleared of snow on both sides of the axis (at least 10 m) and marked with milestones (every 15-20 m). Since the traffic on the highway is one-way, the road with reverse traffic should be laid at least 100 m apart. The thickness of the ice is measured by punching holes 5 m apart (near the coast the distance is reduced to 3 m), the diameter of the holes is from 6 to 10 cm. The holes are located according to the principle of chess squares at a distance of 5 m from the axis in both directions. For safety, they are fenced with a snow embankment around the circumference and covered with wooden shields. Any “hanging” ice that occurs is broken down mechanically. Measurements are taken by the local hydrometeorological service every 5 days, and more often in case of thaws.

In addition to the weight of the equipment, adjustments are made for traffic intensity using the formula:

Htr = na P

It takes into account:

• H – ice thickness;
• n – traffic intensity coefficient (with a traffic volume of 500 vehicles per day, n is equal to 1, if 1 is 500, then 400 is 0.8, etc.);
• a – load characteristic indicator (wheeled, tracked);
• P – load mass, i.e.

The formula can be supplemented depending on local conditions.

As you can see, it is much easier to secure the movement of one person, but only if this person follows the rules. Ultimately, the table of permissible ice thickness (and load on it) when organizing the crossing of equipment will look like this:

Permissible load, t	Required ice cover thickness (cm), taking into account the average daily t for the past 3 days			Distance between cars, m
	– 10 ° and below	– 5 °C	With a short-term thaw to 0 °
Tracked vehicles
4	18	20	28	10
6	22	24	31	15
10	28	31	39	20
16	36	40	50	25
20	40	44	56	30
30	49	54	68	35
40	57	63	80	40
50	63	70	88	55
60	70	77	98	70
Wheeled vehicles
3,5	22	24	31	18
6	29	32	40	20
8	34	37	48	22
10	38	42	53	25
15	46	50	64	30

Methods of transportation

In order not to drive a car on the ice, some fishermen leave it on the shore and then move on their own. Travel methods:

• By ski . When traveling on skis, it is enough for the thickness to be at least 8 centimeters. It is good if the surface is covered with a small layer of snow, since the skis slide too much on a clean surface. This method of transportation is often used by fishermen who come to fish by public transport.
• On snowmobiles . A snowmobile is a heavy vehicle and can only be used if its thickness is more than 15 centimeters. It is advisable to have a small layer of snow on the surface.
• Ice crossings . If you need to reduce the distance between two points, you can use legal ice crossings. The thickness in these places is more than 30 centimeters and you can easily move along them by car.

Amendments and clarifications

When using the table, it should be taken into account that the average daily temperature and “ideal” conditions for the formation of the “freshwater shellfish” type of ice are taken. The thickness of porous ice will have to be doubled. If there is salt water in the reservoir, the correction factor is reduced to 1.2. With frequent thaws, the carrying capacity of each piece of equipment is determined practically.

If necessary, the ice cover is thickened artificially by clearing the space, pouring water on it and waiting for the layers to freeze. If it is necessary to transport equipment to the site of diving work in places where ice covers sea bodies, the conditions change as set out in the first table of the article.

But let us return once again to the requirements of behavior in winter on a river or pond, valid for a person, and especially for children, who are more often than adults, unreasonable. It is believed that ice for a person to be safe on it must be at least 10-15 cm (depending on the water - fresh or salt). In the case of mass events on ice, the norm increases to 25 cm. You should also know how to behave if someone (or yourself) falls through the ice, because panic can lead to a sad outcome.

Rules of conduct on thin ice

permissible and safe thickness of ice when moving on it

1. Certification of emergency rescue teams and rescuers in Russia
2. RESCUER CERTIFICATION
3. Landing of rescuers, evacuation of victims
4. FOR RESCUE AND FIREFIGHTERS
5. Qualification characteristics of rescuers
6. Criteria for assessing special training of rescuers
7. Criteria for assessing the level of psychological training of rescuers
8. Medical protection of the population and rescuers in emergency situations
9. INTERNATIONAL AND HUMANITARIAN ACTIVITIES OF RESCUE EMERCOM OF RUSSIA
10. For professional training of rescuers of the Ministry of Emergency Situations of Russia
11. Normal movement.
12. Training (rescue training curriculum

At an air temperature of 0°C and below, water changes from a liquid state to a solid state (crystallizes), and ice forms.
On water surfaces, the thickness and strength of ice depend on the speed of water flow, its composition and the presence of aquatic vegetation. Smooth ice forms on a smooth, wind-protected water surface. Old (pack) ice is covered with hummocks, which appear as a result of ice compression. When large, heavy ice floes collide, grated ice is formed between them, unsuitable for movement.

The thickness of the ice, especially in fast water, is not the same everywhere. It is thin near the coast, on rapids, in the area of ​​rifts, near rocks, at the confluence of rivers, their confluence with the sea (lake), near frozen objects on the bends and bends of rivers. The most dangerous ice is under snow and snowdrifts. Danger when moving on ice is represented by ice holes, ice holes, holes, cracks, hummocks, and places of contact between melting ice and moving ice.

The movement of rescuers on ice requires compliance with increased safety measures. An ice thickness of 10 cm in fresh water and 15 cm in salt water is considered safe for one person. To determine the thickness of the ice, it must be drilled (cut through).

The reliability of the ice is checked by one rescuer walking across it (light), who must be secured with a rope for safety reasons. If, when moving on it, the ice makes characteristic sounds - cracking, then you cannot walk on it. If the ice breaks, you need to throw off heavy things, get out to the surface of the ice, lie on your stomach, lean on a pole, skis or ski poles and crawl to the shore.

Particular care must be taken when driving on ice that is covered with snow or water. When jumping from one ice floe to another, the support points should be no closer than 50 cm from the edge of the ice.

It is not recommended to gather on the ice in groups of several people or store cargo in one place. The safe distance between rescuers walking on ice should be 5 m or more.

In winter, you can drive vehicles and transport goods on ice. The safe ice thickness depending on the weight of the load and the vehicle is presented in the table.

When moving in hummocks, you should only step on solid ice blocks.

Rules of conduct on thin ice

When the seemingly strong ice for safe movement is replaced by porous and brittle, you may suddenly find yourself in the water, pull yourself together and follow the recommendations:

1. Spread your arms to the sides so that you can lean on them without breaking the edges of the “font” and not choking.
2. You will have to crawl out of the hole, avoiding impetuous movements. If you have ice awls and a rope, use them to pull yourself up.
3. The basic rule: do not rely on individual areas of a small area, but try to position yourself so that the largest possible area serves as support.
4. Roll away from the edges of the hole, and when you get to your feet, do not run, move slowly and without raising your feet above the ice surface.
5. When helping someone who has fallen through, find something that will help expand the support area (sports equipment, plywood, plastic).
6. Do not stand on the edge of the hole, act at the optimal distance.
7. Throw a rope to the person caught in the hole and pull with even movements, helping to get out.
8. When you get home, change the victim’s clothes, give him tea (without added alcohol!) and call an ambulance.

Behavior rules

Rescuers operating in conditions where movement on ice is required must remember:

1. When choosing a route, you need to remember about drifting ice (on the sea, lake), find out the speed and direction of the current and wind.
2. It is worth stocking up on anti-slip devices.
3. On water with currents, the thickness of the ice can be different everywhere.
4. In swamps, unlike rivers, the ice is stronger in the center and weaker at the edges.

Video about the rules of being on ice

Test of strength

When you arrive fishing, the first thing you should do is check the surface for strength. It is very important! If it turns out to be thin, the ice will crack and the person will fall into the water. Test of strength:

1. Before reaching the surface, they evaluate it. The color of the ice that can withstand a person will be blue or greenish, and its surface will be absolutely smooth, clean and transparent.
2. The first steps on the surface are taken carefully. You need to return if, after walking a short distance, the ice under your feet begins to bend and crack. If the distance covered is long, then the first thing you need to do is distribute the weight correctly. To do this, they lie down with their legs spread apart and carefully crawl towards the shore.
3. You can check the thickness using a stick or pick, which you always take with you. If you tap the surface with a stick and a characteristic crack appears, this means that it is very thin and fragile. Sometimes during such actions, water comes out.

You need to know that it is easy to fall into the water if you test your strength with a kick. Therefore, under no circumstances should this be done. You can determine that the surface is fragile and should not be accessed by the following signs:

• If the color of the ice is yellow or gray, then you cannot move on it. It is fragile and can fail immediately. In a few days, its thickness will become greater, then you can safely go fishing.
• Water flows out of the holes.
• The surface cracks or squishes.
• During a snowstorm, the snow freezes and the ice surface acquires a loose, spongy structure. You cannot go out on this ice if it formed after the first frost.

Today you can find out the strength and thickness of ice for fishing on a large body of water from the forecast of the Ministry of Emergency Situations, which are regularly published.

Rules of conduct on a frozen pond

1. Do not experiment with testing the strength of the cover with your feet; take a pole with you.
2. Find existing, well-trodden paths.
3. If you are one of the first to build such a walking trail, test the strength of the ice in front of you with a stick, and avoid places that do not inspire confidence.
4. Remember the signs of a fragile coating: cracking, mobility, the appearance of water above the surface. If this happens, move away from this place with your feet wider, slowly, or even crawling.
5. You cannot move in a group (there should be a gap of at least 5 meters between travelers or skiers), with skis fastened to your feet, and with ski poles attached to your hands.
6. Fishermen need to calculate the number of holes in a certain area and drill them at a considerable distance from each other.
7. If you have a load (satchel, backpack), it is better to secure it with a rope and drag it at a distance.
8. If there is a need to overcome a section of fragile ice, go there with a belayer. Even moving at a distance of 5 meters, he will provide assistance in the event of an accident.
9. If you have the opportunity, it is best to drill a hole and measure the thickness of the ice before your winter hike.
10. It is not recommended to fish near melted or damaged areas of ice.
11. Stock up on twelve meter (or longer) rope, there should be a load at one end.

How to move on ice

It is necessary to move slowly across a frozen body of water until the strength has been thoroughly checked. You cannot make sudden movements or jump on the surface. If the ice is cracked, then you need to move away from the dangerous place, moving with leisurely sliding movements.

You must take with you a long rope (10-15 m) with a load at the end, so that in an emergency you can help another person or use the device yourself.

If the ice surface cracks and breaks, then you cannot quickly run away from the dangerous place. First of all, a person needs to free himself from the load, lie on his stomach, spread his arms wide and crawl out of the danger zone in the direction from which he came.

If a fisherman falls into a hole, the main thing is not to panic, but to remain calm and begin to gradually get out.

Do not grab the edges with your bare hands. It is necessary, having gathered your strength, to try to throw first one leg over the edge of the hole, then the other. After this, having rolled away, you should literally crawl away from the dangerous place in the direction where the ice is strong enough.