1. Author: Lototska Olena V.
Introduction in hygiene and ecology.
Basic laws of hygiene.
Principles of the hygienic setting of norms.
Hygienic value of sun radiation, physical properties and chemical composition of air environment.
Author: Lototska Olena V. 1

2. THE PLAN Introduction in hygiene and ecology. Basic laws of hygiene.
Bases of preventive and current sanitary supervision.
Principles of the hygienical setting of norms.
Cosmosphere, sun radiation and health.
Hygienical value of sun radiation, physical properties and chemical composition of air environment.
Hygienical value of constituents of biosphere (atmosphere, hydrosphere, litosphere).

3. Introduction

4. Health
is defined as a state of complete physical, mental and social well-being and not merely absence of disease or infirmity.

5. health of the population medical etiological factors (8 -10 %)
pollution of an environment (17-20 %)
  way of life (49-53 %)
health of the population
genetic factor
(18-22 %),
medical etiological factors (8 -10 %)

6. To promote and maintain a state of health an individual needs the following prerequisites:
Supply of fresh air and sunlight
Safe and potable water supply
Balanced diet
Healthful shelter
Adequate clothing hygienic environmental sanitation
Protection from communicable and other avoidable afflictions
Complete sense of protection and security both socially and economically
A congenial social and cultural atmosphere.
Regulated way of life with proper rest and relaxation and good and simple habits.

7. PROPHYLACTIC MEDICINE
MEDICAL
Object of studying:
sick man
PROPHYLACTIC MEDICINE
Object of studying: healthy man, and groups of the practically healthy people

8. Hygiene is a basic preventive science in medicine
Hygiene is a basic preventive science in medicine. It generalizes all dates of theoretical and clinical disciplines in the field of prophylaxis, integrates knowledge’s about complex influence of an environment for health of the man, work out principles and systems of preventive measures.

9. preserving and improving health
Basic aim of hygiene –
preserving and improving health
Professor Winslow defined aim of hygiene as "science and art of (i) preventing diseases, (ii) prolonging life, and (iii) promoting health and efficiency through organized community effort for (a) the sanitation of the environment, (b) the control of communicable diseases, (c) the education of the individual or personal hygiene, (d) the organization of medical and nursing services for the early diagnosis and preventive treatment of disease, and (e) the development of the social machinery to ensure everyone a standard of living adequate for the maintenance of health, so organizing these benefits as to enable every citizen to realize birth right of health and longevity".

10. It has many aspects:
personal hygiene (proper living habits, cleanliness of body and clothing, healthful diet, a balanced regimen of rest and exercise);
domestic hygiene (sanitary preparation of food, cleanliness, and ventilation of the home);
public hygiene (supervision of water and food supply, containment of communicable disease, disposal of garbage and sewage, control of air and water pollution);
industrial hygiene (measures that minimize occupational disease and accident);
mental hygiene (recognition of mental and emotional factors in healthful living) and so on.

11. Main tasks of hygiene are the following:
3. Scientific substantiation and working out of the hygienic norms, rules and measures, which help use maximum positively influencing on an organism of the man the factors of an environment and elimination or restriction up to safe levels unfavourable operating ones.
1. Studying the natural and anthropogenic environmental factors and social conditions affecting the health of a human.
2. Studying the laws of the impact of environmental factors and conditions on the human body or population.
5. Prediction of the sanitarian situation for the nearest and remote perspective in view plans of development of the national economy. Definition of appropriate hygienic problems, which implying from prognostic situation and scientific working out these problems.
4. Introduction in practice of public health services and national economy developed hygienic recommendations, rules and norms, check of their effectiveness and perfecting.

12. Basic methods of hygienic researches

13. 1. Methods of environment studying
Methods of hygiene
1. Methods of environment studying
2. Methods of studying of environmental influence on human organism and health

14. Methods of environment studying
Methods of sanitary examination with further sanitary description
Instrumental and laboratory methods
Physical
Biological
Sanitary-statistic
Geographical
chemical

15. Methods of experimental investigation
Methods of Studying of Environmental Influence on Human Organism and Health
Methods of natural observation
Methods of experimental investigation
1.Clinical
1.Experiment with models of natural condition
2. Physiological
3. Biochemical
4. Toxicological
2.Laboratory experiment on animals
5. Sanitary-statistic
3.Laboratory experiment on humans
6. Medical-geographical

16. “Prevention is better than cure” is an old saying
“Prevention is better than cure” is an old saying. Preventive medicine deals with the measures to protect the individuals from the diseases, and to keep them in a state of positive health. For this we have to ensure all the above-mentioned prerequisites required for the maintenance of positive health. The environments must be hygienic, with supply of fresh air, safe potable water and balanced diet.

17. People in ancient societies were concerned about personal hygiene and sanitation for religious reasons. The Bible contains many rules for cleanliness, and describes public health measures still important today. These include quarantining the sick to prevent the spread of disease and avoiding contact with objects used by sick people.
The Greek physician Hippocrates first made the connection between disease and natural environmental factors in the 4th century bc. His treatise Airs, Waters, and Places described how diseases can result from way of life, climate, impure water, and other environmental factors. For the next 2000 years, it was the most widely used text on public health and epidemiology.

18. Ancient Romans adopted Greek ideas about public health after colonizing Greece in the 1st century bc. Rome's greatest contributions to public health involved sanitary engineering. They built aqueducts to supply Rome with pure water and a public sewer system to carry away wastes, as well as public baths and hospitals. The Roman government also hired physicians and assigned them to villages to care for the poor.

19. After the Roman Empire collapsed in ad 476 public health efforts were forgotten and unsanitary conditions returned. Millions of people died when great epidemics of smallpox, leprosy, bubonic plague, tuberculosis, and other diseases swept across Europe in the Middle Ages (5th to 15th centuries ad).
The environments must be hygienic, with supply of fresh air, safe potable water and balanced diet. This aspect of preventive medicine started gaining more importance from 18th century onwards with the discovery of various vaccines and sera for the protection against various diseases like small pox, cholera, plague, whooping cough, tetanus, tuberculosis, poliomyelitis etc.
Edward Jenner discovered vaccination against small pox in 1796.
The discovery of causative agents of the diseases by Louis Pasteur ( ) and Robert Koch ( ) gave a great fillip to the science of preventive medicine.
Von Behring ( ) brought up the principle of serum treatment and use of anti-sera in various diseases.

20. Environmental Sanitation
The word sanitation is derived from the Latin word Sanitas which means a state of health.
Environmental Sanitation means the control of all those factors in man's surroundings, which cause or may cause adverse effects on his health. The sanitarian directs his efforts towards hygiene of water and food supply, hygienic disposal of human wastes, hygiene of housing and control of vectors and rodents etc.

21. physical factors social factors biological factors 1. customs
Ecology is constituted by the total environment of man. The environment of modern man is partly natural and partly man-made.
physical factors
social factors
biological factors
1. customs
1. pathogens,
1. air
2. beliefs
2. water
2. microorganisms as well as living beings
3. laws
3. food
4. peculiarities
4. buildings
3. vectors
5. modes of living of human beings
4. plants

22. Hygienic standardization:
Environmental standards are definite ranges of environmental factors which are optimal or the least dangerous for human life and health.
In Ukraine basic objects of hygienic standardization are:
MAC – maximum admissible concentration (for chemical admixtures, dust and other hazards)
MAL – maximum admissible level (for physical factors)
LD – dose limit (for ionizing radiation)
Optimum and admissible parameters of microclimate, lighting, solar radiation, atmospheric pressure and other natural environmental factors.
Optimum and admissible daily requirements in food and water.

23. Basic objects which are under the hygienic norms setting can be divided into two groups.
The first group contains factors of anthropogenous origin which are unfavorable for human being, and are not necessary for the normal life activity (dust, noise, vibration, ionizing radiation, etc.). MAC, MAL and LD are those parameters which are set for this group of factors.
The second group contains factors of natural surrounding which are necessary (in certain amount) for normal life activity (food-stuffs, solar radiation, microclimatic factors and others). For this group the following parameters, must be set: optimum, minimum and maximum admissible parameters.

24. Let's study the methodical scheme of hygienic norms of substantiation using, the example of MAC for some toxic substance.
The first stage is study physical and chemical properties of the substance, elaboration of methods of quantitative determination of this substance in different subjects, determination of its regimen of action on the human (duration, interruption, changes of intensity), ways of getting into the organism, study migration in different elements of the surrounding, mathematical prediction of duration of existence in different surroundings.
The second stage is study direct influence on the organism. It is started from 'sharp' experiments the main purpose of which is getting initial toxicometric data about the substance (determination of LD50, or LC50 threshold of strong action (LIMac) and other. With the knowledge of physical and chemical properties of the substance, its initial toxicological characteristics and approximate level of MAC can be calculated.

25. The third stage - is conduction of 'subsharp' experiment during l-2 months for determination of cumulating coefficient and the most vulnerable physiologic systems and organs specification of mechanisms of action and metabolism.
The fourth (basic) stage is carrying out chronic experiment which lasts 4-6 months in the case of modelling of working conditions, communal conditions, in study processes of aging or induction of tumours.
During the experiment integral parameters are studied. They reflect condition of animals, degree of strain of regulative systems, functions and structure of organs which take part in processes of metabolism (activity of enzymes), influence of functional loadings.
Numbers of MACs of toxic chemical substances in the Ukraine are various:
- for the air of working zone - more than 800,
- water- 700,
- atmosphere air- 200,
- food-stuffs - more than 200,
- soil - more than 30.

26. The first law of hygiene
can be formulated as follows: the infringement of level of health of the people (disease, decreasing of the resistance, immunological status, adaptation-compensatory opportunities of organism), caused by physical, chemical, biological and psychogenic etiological factors, can occur only at presence of three driving forces:
source of pollution,
mechanism of its influence or ways of its transference
and human susceptible organism.
At the absence of one of these conditions, the disturbances of health will not take place.

27. What is pollution?
The word comes from the Latin pollutus, which means made foul, unclean, or dirty. Some is obvious like smoke which you can see but much of it is not obvious at all. Yet you're eating it and drinking it and breathing it most of the time. And what is worse is that all this muck affects all other life on Earth.
You can find pollution made by people just about everywhere on the planet. Even remote places like the Arctic are badly polluted by nasty chemicals made by people. The polar bears and seals there have poisonous chemicals made by people in their bodies and so do the Inuit people who live with them. These nasty things kill many animals and make others sick -- including penguins in the Antarctic.

28. On a degree of danger distinguish four groups of chemical substances – pollutes:
I - especially high toxic (middle death doze -LD5о - is lower than 50 mg/kg of weight of body);
II - high toxic (LD5о = mg/kg);
Ш - middle toxic (LD5о = mg/kg);
IV - low toxic (LD5о- more than 1000 mg/kg)
The concept about first driving force of process of change of level of health allows to study laws of change of polluting substances in an environment, their decomposition and transformation under influence of the physical and chemical factors of an environment. The basic purpose of these measures is the decreasing of concentration of polluting substances in an environment up to a level, which is safety for health of the population.

29. The following ways of toxic, radioactive and biological agents transmission are possible
AIR
MAN
polluting substance
water
MAN
polluting substance
Animals
Plants
polluting substance
SOIL
MAN

30. Major condition of high stability of the organism to adverse factors of environment is healthy way of life, excluding the using of alcoholic drinks, smoking, other harmful habits, rational nutrition, rational mode of work and rest, observance of rules of personal hygiene, using of wide improving opportunities of physical culture and sports, self preparing.

31. The second law of hygiene
The second law (negative anthropogenic action) - people unfavorably influence on the environment in connection with their physiological, domestic and industrial action.
During the process of live the man allocates in environment excrement (faces, urine), which are very dangerous in the epidemic and sanitary attitude.
Human activities can release substances into the air, water and soil some of which can cause problems for humans, plants, and animals.

32. Traditional forms of pollution include air pollution, water pollution, and radioactive contamination while a broader interpretation of the word has led to the ideas of ship pollution, light pollution, and noise pollution.
Serious pollution sources include chemical plants, oil refineries, nuclear waste dumps, regular garbage dumps (many toxic substances are illegally dumped there), incinerators, PVC factories, car factories, plastics factories, and corporate animal farms creating huge amounts of animal waste. Some sources of pollution, such as nuclear power plants or oil tankers, can release very severe pollution when accidents occur. Some of the more common contaminants are chlorinated hydrocarbons (CFH), heavy metals like lead (in lead paint and until recently in gasoline), cadmium (in rechargeable batteries), chromium, zinc, arsenic and benzene.
Water pollution
Air pollution

33. Common Sources of Primary Pollutants Pollutants
Source
 Pollutants
Chemical Formulae
Cars, Trucks, Buses
   Nitrous oxide,      carbon monoxide,      carbon dioxide,     hydrocarbons 
NO2   CO  CO2  CxHy
                   
 Industry
  Nitrous oxide,      carbon monoxide,      carbon dioxide,      hydrocarbons   + others 
        NO2           CO          CO2          CxHy
 Aerosol cans 
  CFCs         (chlorofluorocarbons),     hydrocarbons 
  Various
Burning   Coal
  Carbon monoxide,     carbon dioxide     sulfur dioxide  
        CO          CO2          SO2 

36. There are several main types of pollution and well-known effects of pollution which are commonly discussed. These include
smog,
acid rain,
the greenhouse effect,
and "holes" in the ozone layer.
Each of these problems has serious implications for our health and well-being as well as for the whole environment.

37. Acid rain forms when moisture in the air interacts with nitrogen oxide and sulphur dioxide released by factories, power plants, and motor vehicles that burn coal or oil. This interaction of gases with water vapour forms sulphuric acid and nitric acids. Eventually these chemicals fall to earth as precipitation, or acid rain. Acid rain pollutants may travel long distances, with winds carrying them thousands of miles before they fall as dew, drizzle, fog, snow or rain.

38. Hazards of Acidic Rain :.
Discoloration of houses,
Rusting of metals.
Damage of crops.
Skin cancer
Damage to marine life
Lead poisoning due to damage to lead pipes.
Prevention:
i. Treatment of industrial smoke
ii. Increase plant growing i.e. Forestation

39. Green House Effect:
Green houses are glass huts seen in hilly areas and in the agricultural processing areas.
Mechanism : When light falls on any surface which is transparent, some rays are reflected and some are refracted. A process of partial retention of light takes place in the green house, so temperature in the glass house is increased.
Causes of Green house effect:
The air pollution causes emission of gases like
CO2, CH4, CO, CFC's,NO2,,Chlorine, Methyl chloroform
These gases are known as Green house gases. These gases cause partial retention of light in the air and so temperature of the atmosphere increases

40. Hazards of Green House Effects:
Global warming
Increased evaporation from sea.
Melting of Ice at poles of earth.
Increase in sea level.
Floods.
Disturbance at coastal areas due to increased sea level.
Prevention:
Decreased industrialization
Treatment of Industrial smoke
Check unfit automobiles.

41. Damage to the ozone layer is primarily caused by the use of chloroflurocarbons (CFCs). Ozone is a form of oxygen found in the earth's upper atmosphere. The thin layer of ozone molecules in the atmosphere absorb some of the sun's ultraviolet (UV) rays before it reaches the earth's surface, making life on earth possible. The depletion of ozone is causing higher levels of UV radiation on earth, endangering both plants and animals.

42. The third law of hygiene (of natural pollution)
The environment is polluted not only under the action of people, but some pollutants come from natural sources.
Volcanoes spew out ash, acid mists, hydrogen sulfide, and other toxic gases.
Sea spray and decaying vegetation are major sources of reactive sulfur compounds in the air.
Forest fires create clouds of smoke that blanket whole continents.

43. Trees and bushes emit millions of tons of volatile organic compounds (terpenes and isoprenes).
Pollen, spores, viruses, bacteria, and other small bits of organic material in the air cause widespread suffering from allergies and airborne infections.
Storms in arid regions raise dust clouds that transport millions of tons of soil and can be detected half a world away.
Bacterial metabolism of decaying vegetation in swamps and of cellulose in the guts of termites and ruminant animals is responsible for as much as two-thirds of the methane (natural gas) in the air.

44. The fourth law of hygiene – is the law of positive anthropogenic influence on environmental of human society.
However we must not think, that the environment is absolutely defenseless in front of the activity of the man. The nature has huge resources of self-preservation, self-updating, self-regulation, maintenance of ecological balance, self-cleaning, but these reserves are not boundless.

45. Factors Which Keep the Composition of Air Constant
Wind, which dilutes, sweeps away or aspirates the impurities and gets replaced by pure air.
Rain, which washes the air and removes gases as well as suspended impurities.
Oxygen and ozone, which oxidise the organic matter present in the air.
Plants absorb CO2 and give off oxygen in sunlight. During sunlight, chlorophyll present in green leaves of the plants absorbs carbon from carbon dioxide of the atmosphere and gives off free oxygen, but at night this process gets reversed.
Sun affects the temperature, pressure and volume of air. Thus heating of air during the day and its cooling at night brings about the air movements.
Changing weather and other climatic and meteorological factors affect the direction and velocity of air movements over vast a tomospheric areas.

46. The fifth law of hygiene
The fifth law of hygiene is the law of inevitable negative influence of the muddy environment on health of the population.
People also become ill through exposure to hazards in the environment. Many diseases are linked to environmental problems such as polluted drinking water, poor waste disposal and air and exposure to mosquitoes and other carriers of disease.

47. Effects of Air Pollution
Air pollution can affect our health in many ways with both short-term and long-term effects. Different groups of individuals are affected by air pollution in different ways. Some individuals are much more sensitive to pollutants than are others. Young children and elderly people often suffer more from the effects of air pollution.
People with health problems such as asthma, heart and lung disease may also suffer more when the air is polluted. The extent to which an individual is harmed by air pollution usually depends on the total exposure to the damaging chemicals, i.e., the duration of exposure and the concentration of the chemicals must be taken into account.

48. Examples of short-term effects include irritation to the eyes, nose and throat, and upper respiratory infections such as bronchitis and pneumonia. Other symptoms can include headaches, nausea, and allergic reactions. Short-term air pollution can aggravate the medical conditions of individuals with asthma and emphysema. In the great "Smog Disaster" in London in 1952, four thousand people died in a few days due to the high concentrations of pollution.
Long-term health effects can include chronic respiratory disease, lung cancer, heart disease, and even damage to the brain, nerves, liver, or kidneys. Continual exposure to air pollution affects the lungs of growing children and may aggravate or complicate medical conditions in the elderly. It is estimated that half a million people die prematurely every year in the United States as a result of smoking cigarettes.

49. Health Effects Air Pollutant Carbon Monoxide (CO)
Colourless and odourless gas.  Reacts with haemoglobin in preference of oxygen. This reduces the amount of oxygen being carried around the body and can result in suffocation. Fortunately, this reaction is slow and requires very high concentrations before advserse effects are felt.
Nitrogen Dioxide (NO2)
Brown poisonous gas.  Effects trachea and lungs causing respiratory problems.
Ozone (O3)
Colourless gas, slightly sweet odour at low concentrations.  Causes eye irritations at concentration of 0.3ppm and respiratory problems at higher concentrations
PAN gas
Effects eyes, nasal passages and respiratry system.

50. The sixth law of hygiene
The sixth law of hygiene is the law of positive influence of the factors of a natural environment on health of the population.
The natural factors of the environment (air, water, good-quality food) have a positive influence on people’s health. They provide preservation and strengthening of the human health

51. Good nutrition is a basic component of health
Good nutrition is a basic component of health. It is essential for the attainment of normal growth and development. Not only physical growth and development, but also the intellectual development, learning and behavior are affected by malnutrition. In short, nutrition affects human health from birth till death.

52. Air is vital to maintain life and serves to ensure a constant supply of life giving oxygen to the body through the process of respiration. One can refuse polluted food and water but not the polluted air. An unlimited, relatively clean air is necessary for comfortable and healthful living.
Functions of Air
1. It serves to maintain Life through constant oxygen supply.
2. It helps in regulation of body temperature; cooling power of the air being an important factor.
3. It helps in functioning of sensations like smell and hearing.
4. The adverse function is through the polluted air, which be­comes a source of spreading various diseases, whether bacterial or otherwise.

53. Impurities due to Respiration Inspired air Expired air
Oxygen
20.95 %
16.50 %
Nitrogen
79.02 %
79.06%
C02
0.04%
4.44%
Water vapours
Varies
Saturated
Temperature
As of body temperature

54. The sun is a source of electromagnetic energy including radio waves, infrared, visible light, ultraviolet, x-rays, gamma rays, and cosmic rays. Each band has its own characteristic wavelengths and properties as a result of wavelength.
Visible light is "visible" because its wavelengths can be detected as various colors by the human eye. Ultraviolet, although invisible, also has various wavelengths and properties.
UV-A, UV-B, and UV-C are part of the ultraviolet spectrum and we are usually exposed to some of each every day. UV exposure can be harmful or harmless depending on the type of UV, the type of exposure, the exposure duration, and individual differences in response to UV.

55. Wavelength (nanometres, nm) Relevance to life on earth
Category
Wavelength (nanometres, nm)
Relevance to life on earth
Cosmic rays
Dangerous and potentially cancer-producing, but penetrate to Earth only in insignificant amounts
Gamma rays
0.0001
X-rays
0.01
Dangerous and potentially cancer-producing, but penetrate to Earth only in insignificant amounts; also used artificially in medicine
Ultraviolet (UV)
Causes short- and long- radiation term damage to exposed living matter, particularly, in humans, sunburn, photoageing and cancer of the skin
Visible light
Allows us to see; enables plants to create food molecules; drives human biorhythms; lifts human mood
Infrared radiation
800-17,000
Warms our bodies
Radiofrequency
100,000,000
Harmless and of no known radiation significant effect; used artificially for tele- communications .

56. Electromagnetic portion of the solar radiation
Wave lenght , nanometers (nm).
Frequency band
> 100 000
Far-infrared region
100 000 – 10 000
Infrared region
10 000 – 760
Visible (optical) region
760 – 400
Ultraviolet region
400 – 120
Terminal ultraviolet region
120 – 10
Soft X-rays
10 – 0,1
High-energy (gamma) rays
< 0.1
The light you can see has a wavelength of (nm).
UV rays
region А –
long-wave ultraviolet radiation:
 = nm;
region В –
middle-wave ultraviolet radiation:  = nm;
region С –
short-wave ultraviolet radiation:  = nm.

57. The solar ultraviolet radiation wave lenght less then 290 nm is completely absorbed by oxygen and ozone of the upper atmosphere. Atmospheric pollution by factory waste helps the ozone layer destruction resulting in appearance of “ozone holes”. The shortest and the most harmful UV waves reach the earth surface through these “ozone holes”.

58. Positive effects UV rays are necessary
for our body to produce vitamin D, a substance that helps strengthen bones and safeguards against diseases such as Rickets. Some scientists have shown that Vitamin D lowers the risk of getting some kinds of internal cancer, like colon cancer.
UV light is also used as a therapy for psoriasis, a condition in which the skin sheds its cells too quickly, resulting in itchy, scaly patches on various parts of the body. When exposed to ultraviolet rays, the growth of the skin cells is slowed, relieving the symptoms.
UV rays are also used in various commercial functions, such as disinfecting fish tanks and sterilizing medical equipment. Animal life makes their own use of these wavelengths too—certain animals can actually see ultraviolet light, and use it to their advantage. Bees use the reflection of UV off of flower petals to guide their pollen collecting. 

59. Is ultraviolet light harmful?
2.1.
Is ultraviolet light harmful?
The difference has to do with the ability of UV rays to penetrate body surfaces.
UV-A is also known as "blacklight" and is generally harmless. It results in skin tanning and is used in medicine to treat certain skin disorders.
UV-B has a very high penetrating ability and prolonged exposure is responsible for some types of skin cancer, skin aging, and cataracts (clouding of the lens of the eye).
UV-C has extremely low penetrating ability and is nearly completely absorbed by the outer, dead layer of skin where it does little harm. It does reach the most superficial layer of the eye where overexposure can cause redddening and painful but temporary irritation, but it cannot penetrate to the lens of the eye and cannot cause cataracts. UV-C is also known as "germicidal UV."

60. Several factors influence the intensity of sunlight and its potential to cause skin sunburn, photoageing and cancer:
Time of day: risk greatest between the hours of 11:00 and 15:00 in the UK, when the sun is highest in the sky
The higher the sun is in the sky, the shorter the distance sunlight has to travel through the atmosphere and the lower the likelihood of the radiation being absorbed or deflected.

61. Time of year: risk greatest during the summer months, when the sun rises higher in the sky
Summer solstice (Northern Hemisphere): UV radiation has the shortest distance to travel through the atmosphere.
Winter solstice (Northern Hemisphere): UV radiation has the greatest distance to travel through the atmosphere

62. Cloud cover: risk greatest on a cloudless day, although light cloud only mildly reduces this risk; even heavy cloud removes only 50 to 90 per cent of the radiation
Geographical latitude: risk greatest near the equator, where the sun always rises high in the sky
UV intensity increases with altitude because of the reduced distance the radiation must travel through the atmosphere.
Clouds only moderately reduce the amount of UV radiation reaching the ground - you can still burn on a cloudy summer's day.

63. Reflection: risk greatest near UV-reflecting surfaces, including sand, snow and rippling water
Some surfaces reflect UV radiation well, allowing more of it to reach your skin and increasing your risk of damage
Wind and water: risk not affected by the cooling effect of these
Amount of sky visible: risk greatest when lots of sky can be seen; up to two-thirds of UVB radiation arrives indirectly at all angles from the atmosphere (scattering) rather than just direct from the sun, so the risk is reduced by only as little as a third if the sun is directly obscured but wide expanses of sky are still visible

64. Six primary comfort variables
Over the years, researchers of human comfort have established the variables that affect a human's thermal sensations and they have established the ranges of these variables within which the average person is comfortable.
Six primary comfort variables
These "comfort" variables include air temperature, relative humidity, air motion, and mean radiant temperature. The mean radiant temperature is the average temperature of all of the surfaces that surround the person in question. These four variables are called the "environmental variables" because they represent the environment surrounding the body.
A second set of variables, called the "personal" variables, are controlled by the individual. The two are the clothing insulation value, termed the "clo" value, and the metabolism rate.

65. Heat Generated
Body
Skin
Sweat
Clothing
Exposed surface
Respiration
Evaporative heat loss
Surface in environment
Radiation
Convection
Sensible heat loss from the skin
Thermoregulation of human organism on 85 % is realized through the skin. The most of the heat (45 %) organism loses by the emitted radiation, 30 % by convection and conduction, 10 % by evaporation (perspiration).

66. High humidity of air sharply decreases heat loss by perspiration
High humidity of air sharply decreases heat loss by perspiration. Heat loss by conduction first of all depends on temperature of subjects contacting with body, and by convection (circulation) - also on speed of air moving.
Heat loss by convection is proportional to square root of speed of air moving (√V). In air temperature 33°C heat loss by convection stops, and in further increase of temperature body heating takes place. If temperature of environment is equal to body temperature heat loss by conduction and radiation stops. Thus, in conditions of high temperature and humidity in absence of air moving adaptive possibilities of thermoregulation are sharply narrowed and tensed.

67. Temperature Temperature is a measure of the amount of heat (average molecular kinetic energy) in a material, such as air. Temperature is the average amount of “moving” energy contained by particles moving around in the atmosphere. Temperature is measured with thermometers that may be calibrated to a variety of temperature scales. The basic unit of temperature (symbol: T ) in the International System of Units (SI) is the kelvin (Symbol: K). In most of the world, the degree Celsius scale is used for most temperature measuring purposes.
Many physical properties of materials including the phase, density, solubility, vapor pressure, and electrical conductivity depend on the temperature. Temperature also plays an important role in determining the rate and extent to which chemical reactions occur. This is one reason why the human body has several elaborate mechanisms for maintaining the temperature at 37 °C, since temperatures only a few degrees higher can result in harmful reactions with serious consequences. Temperature also controls the type and quantity of thermal radiation emitted from a surface.

68. Air Pressure Air pressure is the force of air pushing down on earth
Air Pressure Air pressure is the force of air pushing down on earth. Air pressure due to weather is also known as Atmospheric Pressure. Air pressure is the result of Earth’s gravity pulling on the atmosphere.
                            A barometer is used to measure air pressure. The average pressure exerted by the atmosphere on sea level is 1 bar. The millibar (one-thousandth of a bar) is the unit commonly used to report air pressure. Generally, air pressure decreases with higher altitude. Pretend air pressure is like a column of air reaching into the sky. The higher up the land is, the shorter the column of air is on top of it. A shorter column has less mass and weighs less. As such, there is less air on top of mountains pushing down than there is down in a valley.

69. Water vapor in the air is called humidity
Water vapor in the air is called humidity. Hygrometers are used to measure humidity. Relative humidity is the amount of water vapor in a volume of air compared to the maximum amount of vapor that volume of air could possibly hold. Relative humidity is measured by a psychrometer and reported as a percentage.                            

71. Wind is the movement of air from a location of high pressure to a location of low pressure as pressure equalizes. Wind is described in terms of its direction and speed.
Wind vanes are used to indicate wind direction. Wind vanes point into the wind, meaning they point in the direction from which the wind is coming. Winds are named for the direction from which they are coming. Anemometers measure wind speed. Wind speed is reported in kilometers or miles per hour (km/h or mph), or in centimeters or meters per second (cm/s or m/s).

72. Thank your for attention!