HAZARD is a potential source of damage. Hazard can be specified in part of the nature of the hazard (hazardous processes, phenomena, objects that have a negative impact on human life and health, on technical systems) or the type of expected damage (danger of injury, occupational disease, destruction). In other words, danger is the source of the expected (possible) negative impact of certain factors on a particular object (subject) of impact. If the characteristics of the influencing factors do not match the characteristics of the object (object) of the impact, a hazard phenomenon appears (for example, shock wave, abnormal temperature, lack of oxygen in the air, toxic impurities in the air, etc.).
Danger is a property inherent in complex socio-technical systems. It can be realized in the form of direct or indirect damage to the object (object) of impact gradually or suddenly, and sharply as a result of system failure. Hidden (potential) danger to a person is realized in the form of injuries that occur in case of accidents, accidents, fires; for technical systems – in the form of destruction, loss of control, etc .; for ecological systems – in the form of pollution, loss of species diversity, etc.
Defining signs – the possibility of a direct negative impact on the object (subject) of the impact; the possibility of disrupting the normal state of the elements of the production process, as a result of which accidents, explosions, fires, injuries can occur. The presence of at least one of these signs is sufficient to classify factors as hazardous or harmful.
The number of signs characterizing the danger can be increased or decreased depending on the purpose of the analysis.
TAXONOMY OF HAZARDS
Taxonomy – the word of Greek origin (taxis – arrangement in order + monos – law) – is defined in the dictionary of foreign words as “the theory of classification and systematization of complexly organized areas of activity, which usually have a hierarchical structure.” Thus, taxonomy in science is the classification and systematization of complex phenomena, concepts, objects. Since danger is a complex, hierarchical concept that has many features, their taxonomy plays an important role in organizing scientific research in the field of work safety and allows us to understand the nature of hazards, gives new approaches to the tasks of describing them, introducing quantitative characteristics and managing them.
It is possible to give examples of some existing taxonomies:
- – by nature of origin: natural, man-made, anthropogenic, ecological, mixed;
- – occupational hazards: physical, chemical, biological, psycho-physiological, organizational;
- – on the time of manifestation of negative consequences: impulsive (in the form of short-term effects, for example, a blow) and cumulative (accumulation in a living organism and summation of the action of certain substances and poisons);
- – by localization in the environment: associated with the atmosphere, hydrosphere, lithosphere;
- – in the field of human activity: domestic, industrial, sports, military, road transport, etc .;
- – on the damage caused, social, technical, economic, environmental, etc .;
- – by the nature of the impact on the person: active (they have a direct impact on the person through the energy resources contained in them); passive-active (activated due to energy, the carrier of which is the person himself, surface irregularities, inclines, rises, slight friction between the contacting surfaces, etc.); passive – manifest indirectly (this group includes properties associated with corrosion of materials, scale, insufficient strength of structures, increased loads on equipment, etc. They manifest themselves in the form of destruction, explosions, etc.); voluntary and compulsory dangers: the dangers can be exposed both voluntarily, for example, by doing skiing or mountaineering, and forcibly, working as a lifeguard or fireman at an industrial enterprise, being near the scene at the time of the hazards. This approach allows you to highlight the hazards of production and non-production (risk to the public);
- – by structure (structure): simple (electric current, elevated temperature) and derivatives – generated by the interaction of simple (fire, explosion, etc.);
- – by concentration: concentrated (the burial site of toxic waste) and diffuse (soil pollution by emissions from thermal power plants precipitated from the atmosphere).
Taxonomy is conducted depending on what goal the researcher has set, for example: to evaluate the effects of the influence of the production environment or the environment on the human body.
A significant part of the above hazards does not always lead to the occurrence of incidents, but complicates the performance of work with regulated technology. Taxonomy allows you to highlight the main hazards.
The examples below are typical for hazards arising from the failure of technical systems.
Classification by effects of changes in environmental conditions. Any noticeable deviation from the usual, determined in the course of a long biological evolution of the conditions of human existence leads to injury or disease. The most significant parameters of the human environment, which are important for his normal and safe life, are:
- a) temperature;
- b) ambient air pressure;
- c) external pressure exerted on certain parts of the body;
- g) oxygen concentration;
- e) concentration of toxic or corrosive substances;
- e) the concentration of pathogenic microorganisms;
- g) electromagnetic flux density;
- h) the level of ionizing radiation;
- i) the electric potential difference;
- j) sound and vibration loads.
Impacts associated with an increase or decrease in the temperature of the human body (both from the inside and the outside) can lead to injury or death. Such effects include heat radiation, convection and direct heat transfer from or to the skin, breathing in too cold or hot air, drinking in too cold or warm liquids or solids.
Sudden changes in ambient air caused by air shock waves can cause injury or death.Mechanical injuries occur due to the application of excessive pressure to individual parts of the human body. Mechanical injuries are torn and cut wounds, bruises, fractures, crush, tearing off of parts of the body, injuries affecting vital organs – the brain, heart, lungs, etc.
The decrease in the concentration of oxygen in the air leads to injury and death. A break in breathing occurs if a person drowns or is buried under solid materials. Excess oxygen is also dangerous. With a high concentration of oxygen, fire danger arises sharply.It is well known that the presence of certain substances in the environment leads to illness or death (for example, excessive concentrations of carbon monoxide or dioxide).
Excessive concentration of pathogens is harmful and leads to infectious diseases.For all wavelengths of electromagnetic radiation, there are limits to the intensity beyond which their effects on the human body become hazardous to health.
The human body has adapted to existence in conditions of natural radioactive background, and the contribution of a relatively small technospheric component (nuclear energy in normal operating conditions, medical diagnostics, non-destructive methods of control in technology, etc.) can be considered harmless. Increased dose levels lead to chronic diseases, significant doses cause radiation sickness and death.
The human body is sensitive to the potential difference of the order of tens of volts. The potential difference of hundreds of volts (no matter – DC or AC voltage) may well lead to death.Sound and vibration loads can lead to chronic non-lethal diseases.
Classification by implementation time. In medicine, the terms “acute” and “chronic” have long been used to describe the nature of the disease: a rapidly developing and rapidly flowing disease is called “acute”, a slowly developing and long-term disease is designated as chronic. In medicine, the exact concepts of “fast” and “slow” have never been given. From a medical point of view, the concept of “acute” or “chronic” was in no way associated with the severity of the disease, such an understanding of these terms is preserved when considering the dangers.
It is easy to see that the terms “acute” and “chronic” correspond to the opposite poles of a certain range of values; to draw a strict dividing line between them is very difficult. The term “acute” will relate to hazards for which the time of action does not exceed an hour. The danger will be called chronic if its implementation takes more than a month. Hazards whose implementation period is within the designated interval will be considered as a cross between acute and chronic hazards. Tab. 1.1 illustrates the use of such a classification. Under the time of action of danger refers to the period during which these hazards are born, develop and act. 1 illustrates the use of such a classification.