Сильнодействующие ядовитые вещества

Lecture # 10

 

TABLE OF CONTENTS

ACTION highly toxic substances on the population , protection

CHARACTERISTICS AND HARMFUL highly toxic substances ( SPS )

ACCIDENT with emissions SDYAV

CONSEQUENCES OF ACCIDENTS chemically hazardous objects

POSSIBLE ACCIDENT PREVENTION AND REDUCTION Joo DAMAGES FROM THEM

BASIC RULES OF CONDUCT AND POPULATION IN TROUBLE with emissions SDYAV

 

 

ACTION highly toxic substances

ON POPULATION PROTECTION FROM THEM

 

The most typical accidents that cause serious consequences , are explosions , fires, poisoning the atmosphere and terrain SDYAV , radioactive contamination .

Accidents with expiration ( release ) SPS and contamination of the environment occur in the chemical , petrochemical , pulp and paper, dairy and food industry ( with refrigeration systems and applying them as a refrigerant substances such as ammonia) , water and sewage treatment plants ( using chlorine) as well as during transport SDYAV by rail and by road .

The immediate causes of emissions SDYAV are breaking the rules of storage and transportation , failure to comply with safety regulations , failure of machines , tools , pipes, damaged tanks , etc. It is not excluded defeat for the workers , employees and other categories of people who find themselves in the areas of SPS release .

Highly toxic substances called chemical compounds that , in certain quantities exceeding MAC, have harmful effects on humans , farm animals , plants, causing them damage of varying degrees .

SPS can be elements of the process (ammonia , chlorine , sulfuric acid and nitric acid , hydrogen fluoride ) may be formed on the objects fires economy (carbon monoxide , nitrogen oxide , hydrogen chloride , sulfur dioxide ) .

The destructive effect on people SDYAV possibly as a result of contact of these substances in the form of a liquid droplet on the skin of a person , and as a result of inhalation of vapors . On toxic properties of SPS are mainly related to a group of substances Blood gases and asphyxiating . Symptoms of poisoning by them in most cases are headache , dizziness, blackouts , tinnitus , increasing weakness , shortness of breath , nausea , vomiting , and in severe poisoning , fainting , seizures, loss of consciousness and even death.

In the settlements of infection resistance SPS will be higher than in the open , because the effect of the wind is less pronounced .

In towns and forests of stagnation of the infected couples SDYAV air in production areas , basements, tunnels and communications - are possible formation of relatively high concentrations of vapors. The nature of the toxic effect of certain SPS can vary, for example , pairs of chlorine in a concentration of 0.1-0.2 mg / l can cause death of human inhalation blocked for at least 1 hour, and couples in a concentration of 10-15 mg / l cause a reflex stop breathing at 1-2 breaths . Some of the SPS at high concentrations of vapors can cause skin lesions per person ( with blistering ) .

CHARACTERISTICS OF HARMFUL and potent

Toxic substances ( SPS )

 

In certain occupations may impact on the working of harmful substances . Harmful substances can enter the body through the respiratory system , gastrointestinal tract , skin and mucous membranes.

Step harmful chemicals on the human body due to their physicochemical properties. The group of chemically hazardous and harmful factors on the impact on the human body are divided into the following subgroups:

1. Systemic toxicity - the majority of industrial emissions. These include aromatic hydrocarbons, and amido and nitro derivatives (benzene , toluene , xylene , nitrobenzene , aniline , etc.). Large toxicity have organic mercury compound , organophosphorous agents , carbon tetrachloride , dichloroethane .

2 . Irritant effect are acids, bases, and chloro - fluoro - sulfur-and nitrogen-containing compound ( phosgene, ammonia, nitrogen and sulfur oxides , hydrogen sulphide ) . All of these substances have in common that in contact with the biological tissues , they cause an inflammatory reaction , and primarily affects the respiratory skin and mucous membranes of the eyes .

3 . By sensitizing are in the islands , which, after a relatively short action on the organism causing it more sensitive to this substance. In the subsequent even brief contact with this substance a person has violent reactions , often leading to skin changes , asthmatic phenomena , blood diseases . Such substances include certain mercury compounds , platinum , aldehydes ( formaldehyde) .

4 . Carcinogenic ( Blastomogenic ) substances entering the human body , cause the development of malignant tumors. Currently, there is evidence of carcinogenic risk to humans is relatively small group of chemical compounds found in industrial environments . These primarily include polycyclic aromatic hydrocarbons ( PAH ), which may comprise crude oil , but basically are formed by heat ( above 350 °) processing of fossil fuels ( coal, wood , oil shale ) or incomplete combustion of .

The most pronounced possess carcinogenic activity of 7,12- Dilithium without ( a) - anthracene , 3,4 - benzopyrene , 1,2- benzanthracene . Carcinogenic properties are inherent and products of oil refining and petrochemical industry (heavy oil , tar , cracked residue , petroleum coke , bitumen , oil, soot ) . Possess carcinogenic aromatic amines, which are mainly products of aniline- dye industry , as well as the asbestos dust .

5 . Poisons have mutagenic activity , influence the genetic machinery of germ and somatic cells of the body. Mutations lead to cell death or functional changes . This may cause a decrease of the total resistance of the organism , premature aging , and in some cases severe disease . Exposure to mutagenic substances may affect the offspring (not always the first, and perhaps the second and third generations) . Mutation possess activity , for example, ethyleneimine , urethane , organic peroxides, mustard , ethylene oxide , formaldehyde , hydroxylamine .

6. The substances that affect the reproductive function ( a function of procreation ) , include benzene and its derivatives , carbon disulfide , chloroprene , lead , antimony , manganese , pesticides , nicotine, ethyleneimine , mercury compounds .

There are other types of classifications of harmful substances , for example, an advantageous effect on certain organs or systems of human body , in the main negative impact ( constricting , annoying nerve ( neurotropic ) poisons blood , liver ) at reacted with enzyme systems , the magnitude of the medium lethal dose.

As to its effect on the human body all the harmful podveschestva are divided into four classes:

· Extremely hazardous substances (3,4 - benzopyrene , mercury , lead , ozone, phosgene) ;

· A highly hazardous substances ( nitrogen oxide , benzene , iodine , manganese, copper sulfide , caustic alkali, chlorine) ;

· Moderately hazardous substances (acetone , xylene , sulfur dioxide , methyl alcohol ) ;

· Low hazardous substances ( ammonia, benzene , turpentine, alcohol , carbon monoxide ) .

It should be borne in mind that the low-hazard substances with prolonged exposure at high concentrations can cause severe poisoning.

Hazard class of substances set the table GOST 12.1.007-76 , depending on the maximum permissible concentration ( MPC) for airborne concentrations (mg/m3) , the average lethal dose when administered in the stomach ( mg / kg) , the average lethal concentration in air (mg/m3) , the coefficient of the possible inhalation poisoning ( KVIO ) , areas of acute effect , chronic exposure zone .

MPC hazardous substances in workplace air are given in GOST 12.1.005-76 , there are classes of danger.

Working area is space, up to 2 m above the ground or grounds on which the place of permanent or temporary employees.

First MPC for 40 toxic substances have been approved in our country in 1939 In the current regulatory document them for 800 - the largest in the world list of substances for which exposure limits . With the accumulation of data MPC many substances reviewed and reduced. For example, MPC benzene phases was reduced from 200 to 5 mg/m3 aniline - from 10 to 0.1 mg/m3 10 carbon disulfide to 1 mg/m3.

Let us consider in more detail the most common characteristic of SPS and how to protect against them.

Ammonia (NH3) - a colorless gas with a smell of ammonia (pores of perception - 0.037 mg / l). It is used in the refrigeration industry, to produce nitrogen fertilizers. The dry mixture of ammonia and air (4:3 ) is able to explode . Ammonia is highly soluble in water.

In high concentrations, it stimulates the central nervous system and causes seizures. The most common death comes after a few hours or days after the poisoning of edema of the larynx and lungs. After contact with the skin can cause burns of varying degrees.

First Aid : fresh air , inhaling warm water vapor 10% - r-ra menthol in chloroform , warm milk or soda Borjomi , with suffocation - oxygen , with spasm of the glottis - the heat on the neck , warm water inhalation, contact with eyes, - immediate flushing with water or 0.5 - 1% - solution of alum with the defeat of the skin - wash with clean water , lotions imposition of 5 % - r-ra acetic acid, citric acid or hydrochloric acid.

Protection ! industrial masks mark " K" and " M" in a mixture of ammonia with hydrogen sulfide - " CD " . At high concentrations - insulating gas masks and protective clothing .

Chlorine (Cl) - greenish- yellow gas with a pungent odor . Used in various industries: pulp and paper , textile, manufacturing bleach , water chlorination .

Chlorine 2.5 times heavier than air , so the chlorine cloud will move in the wind direction close to the ground . Chlorine irritates the respiratory tract and cause pulmonary edema. At high concentrations , death occurs from 1-2 breaths at somewhat lower concentrations - breathing stops 5-25 minutes .

First aid: to put on a gas mask and make the affected area of the infection. Complete rest , inhalation of oxygen. In case of irritation of respiratory tract - the inhalation of ammonia , baking soda , washing the eyes, nose and mouth 2% - p - rum soda , warm milk with soda , coffee.

Defense: industrial gas masks mark " B" and " M" , the civil gas masks 1P- 5 , children's gas masks and protective kits for children . At very high concentrations ( 8.6 mg / l) - insulating masks .

Sulfur dioxide (SO2) - a colorless gas with a pungent smell and sweet taste , does not burn or support combustion . Occurs during roasting and smelting of sulphide ores , for smelters in the sulfuric acid is used as a bleaching agent in the textile and curing - in the food industry.

It is highly soluble in water, alcohol , acetic acid and sulfuric acids , chloroform and ether.

Sulfur dioxide irritates the respiratory tract , causing necrosis of cornea . Accompanied by a dry cough, irritation , burning sensation and pain in the throat and chest, watery eyes , and with a strong impact , vomiting, shortness of breath , loss of consciousness. Death can occur from suffocation and sudden cardiac arrest in the lungs.

First Aid : fresh air, oxygen inhalation , rinse the eyes, nose , rinse 2% p - rum soda ; heat to the neck , mustard , warm milk with Borjomi , baking soda, butter and honey .

Defense: prom. masks mark " B" and " M" , civil , children and insulating masks .

Carbon monoxide (CO) - the gas is colorless , odorless and tasteless. Lighter than air. The destructive concentration - 1.2 mg / l Exposure 3 hours deadly - 2 mg / l Exposure 1 hour and 5 mg / L - 5 minutes upon exposure .

Signs of : headache , dizziness , nausea , vomiting , muscle weakness , increased blood pressure , dilated pupils , shortness of breath . In severe cases, a loss of consciousness , impairment of cardiac and respiratory activity , convulsions.

First aid: make the victim into the air , to ensure complete peace and warmth. If necessary, give artificial respiration.

Protection: filter masks brand " INC " and " M" . Civil masks GP -5 and GP-7 with a cartridge DP -1 ( golkolitovy ) . Upon liquidation of the accident using breathing apparatus .

Mercury (Hg) - liquid metal having extraordinary mobility and flowability evaporation . The mercury vapor , like most of its chemical compounds , has a very high toxicity. Actively absorbed by the plaster , wood, rust , textile materials , some brands of linoleum , glass, metal and other materials. The adsorption process is reversible, so the objects and walls in the room are an additional source of contamination by mercury vapor .

Signs of : initial symptoms are non-specific and can be expressed in the nervous system disorder . When severe exposure appears metallic taste in the mouth, headache , nausea , vomiting , abdominal pain , diarrhea with mucus and often with blood, thirst , swelling and bleeding gums , loss of consciousness.

First aid : Immediately terminate your access to the mercury vapor (or mercury ) , remove to fresh air. Rinse the stomach causing vomiting, give a saline laxative (1 tbsp. Tablespoon bitter salt in a glass of water). Heavy drinking milk. Hospitalization.

Protection: filter masks brand "G" or "M". In case of liquidation - insulating masks , rubberized protective clothing , rubber boots , gloves.

To process the apartments you can use:

¨ soap- soda solution ( 4% and 5% soap soda ) ;

¨% solution of chlorine bleach ;

¨% potassium permangonata solution acidified with hydrochloric acid (5 ml per 1 l of solution) .

Acrylonitrile (ACN ) - a volatile , colorless liquid with an unpleasant odor. Soluble in water. Vapors are heavier than air . A pair of NAC accumulate in low-lying areas areas, basements, tunnels. Flammable and explosive. Toxic if swallowed. It is dangerous if inhaled. A pair of NAC cause irritation of the mucous membranes and skin . In combustion releases toxic gases . Inhalation of NAC may lead to death .

Signs of : headache , dizziness , weakness, nausea , vomiting , muscle weakness, low body temperature , sweating , shortness of breath , loss of consciousness, seizures , redness and burning of the skin .

First aid: the victim to fresh air . Wash affected skin with soap and water , mucous membranes, rinse thoroughly with water . If possible, give a snort The acetonitrile .

Protection: filter masks grade of "A" , "M " and " CBF " . Respirators RPG- 67A , RU- 60mA . In case of liquidation - insulating masks , rubberized protective clothing , rubber boots , gloves.

Acid (HnRn) - ( sulfuric, hydrochloric, nitric acid, acetic acid ) are colorless, heavy liquid , readily soluble in water. Strong acids floating in the air , vapors are heavier than air . Strong oxidizers . Corrode metal. Non-flammable . Sulfuric acid causes ignition of organic substances in the presence of nitric explodes mineral oils, alcohol and turpentine. Acids are dangerous if inhaled , swallowed , cause severe skin burns

Signs of : sore throat , shortness of breath , dry cough, irritation , burns the lips, chin, skin , mucous membranes, sharp chest pain , painful vomiting blood, possible spasms and swelling of the larynx. If poisoning nitric acid or its vapors , lips , corners of the mouth , tongue painted yellow .

First Aid : Remove the air, remove contaminated clothing. The affected areas liberally rinse with water and 2% sodium carbonate solution . Urgently hospitalized.

Protection: filter masks mark " B". Respirators RPG- 67A , RU- 60mA . In case of liquidation - insulating masks , rubberized protective clothing , rubber boots , gloves, goggles.

 

Other characteristics table cm .

Some of the SPS and their characteristics

 

SDYAV

Density

temperature

The toxic properties

Decon 

 

g/cm3

boiling point , ° C

affects concentration, mg / l

exposure

Lethal Concentration mg / l

exposure

substance

ammonia

0.68

- 33.4

0.2

6

7

30

water

chlorine

1.56

- 34.6

0.01

14

0.1 - 0.2

14

slaked lime

phosgene

1.42

8.2

0.05

10

0.4 - 0.5

10

alkaline waste and water

sulfur dioxide

1.46

- 10

0.4 - 0.5

50

1.4 - 1.7

50

slaked lime , ammonia water

carbon monoxide

-

- 190

0.22

2.54

3.4 - 5.7

30

-

carbon bisulfide

1.26

46

2.5 - 1.6

1.54

10

1.54

sodium or potassium sulfide

phosphorus trichloride

1.53

74.8

0.08 -0.015

30

0.5 - 1.0

30

lye , ammonia water

hydrogen fluoride

0.98

19.4

0.4

10

1.5

5

lye , ammonia water

prussic acid

0.7

25.6

0.02 - 0.04

30

0.1 - 0.2

15

lye , ammonia water

 

 

The accident with the release of SPS

 

Chemically hazardous object ( X ^ ) - the object of the economy, in an emergency or destruction of which could occur mass destruction of people , animals and plants SDYAV .

SPS have large reserves of chemical, tselyuloznobumazhnoy , defense , oil refining and petrochemical industry, ferrous and non- ferrous metallurgy, mineral fertilizers . Significant reserves SDYAV also focused on the object of Agricultural industry and housing and communal services. Total in Russia for more than 2 thousand different chemically hazardous objects.

Chemically hazardous facilities of the Krasnoyarsk Territory and used them SDYAV

settlement

Hoo

SDYAV

Quantity, t

Achinsk

Achinsk Alumina

sulfuric acid

3000

Achinsk

AGVKP Levoberezhniy OS Achinsk

chlorine

1000

Krasnoyarsk

Synthetic Rubber Plant

NAC

1000

Krasnoyarsk -35

chemical plant

propellant

800

Krasnoyarsk

"Khimvolokno "

carbon bisulfide

400

Krasnoyarsk

Factory " Krastsvetmet "

hydrochloric acid

350

Krasnoyarsk

Pulp and Paper Mill

chlorine

180

Divnogorsk

JSC "Plant of low-voltage equipment "

hydrochloric acid

180

Norilsk

Teplovodogazosnabzhenie Norilsk

ammonia

100

Krasnoyarsk

Plant Medicine

hydrochloric acid

100

Krasnoyarsk

Factory " Krastsvetmet "

chlorine

96

Krasnoyarsk

"Khimvolokno "

ammonia

57

Toxicity - SDYAV property that determines their toxicity , which is characterized by a deadly and lethal threshold concentrations . In the chemical toxicology of the total number of poisons ( chemical in - in , representing a production environment the risk of acute and chronic poisoning ) to the SPS includes those substances which are lethal dose for humans do not exceed 100 mg / kg. For a more precise characterization of the concept of using SPS toksodozy .

Toksodoza - number in the islands ( in terms of weight ) per unit volume and per unit time. Toksodoza characterizes the amount in the islands absorbed by the body for a certain period of time.

If released SDYAV distributed as in the form of gases , vapors , liquids, aerosols.

Aerosols are fine - heterogeneous ( heterogeneous systems) consisting of airborne virtually no settling of solid or liquid particles in size Islands from 10-6 to 10-3 cm ( 0.01 - 10 microns).

Aerosols coarse - heterogeneous ( heterogeneous systems) consisting of airborne fast settling solid or liquid particles in size Islands 10-2 (100 microns).

In describing the ( evaluation ) of accidents at Hoo 's important to know the extent and duration of chemical contamination , as well as other features and performance.

The extent of chemical contamination - the lengthy border ( linear dimensions and area ) displays the accident , destruction of objects containing SPS .

Duration of chemical contamination - the time limit manifestations of accidents , destruction of objects containing SPS .

Classification of accidents at Joo can be made on the scale distribution SDYAV . Damaging properties , duration , and many other features.

Depending on the degree of chemical hazard accidents are divided into:

Accident I degree of chemical hazards - accident due to the possibility of mass destruction and the production staff people living nearby .

Accidents II degree of chemical hazards - accident due to the possibility of mass destruction production staff chemically hazardous enterprises.

Accidents Chemical Safety - an accident in which produces local lesions SDYAV that do not pose danger to the manufacturing plant personnel and the public.

In view of the general classification of the accident on the scale of the consequences could be:

The local (private ) accident - an accident on the Hoo associated with low leakage SDYAV .

The object accident - an accident on the Hoo associated with leakage of the SPS process equipment or piping . Its effects are confined to the territory of the enterprise or object.

Local accident - an accident on the Hoo associated with the destruction of most of unit capacity of a warehouse or SPS . Chemical hazard persists until 6:00 . The consequences are limited to the city, district or region . Cloud reaches residential developments. Are urgently required the evacuation of the nearby residential areas, as well as other activities for the extra protection.

Regional accident - an accident on the Hoo with significant and sometimes multiple , release SPS , which can not be localized within 6 hours or more. The consequences are limited outside of a few areas of the republics . Chemical hazard extends to many towns.

National or global accident - an accident with a complete breakdown of all the major stores SDYAV Hoo or more objects. It is possible in the event of a major diversion in the disaster or the impact of enemy in the war. The consequences include the limits of several republics , large sections of the country and even beyond its limits.

Depending on the nature of the accident SDYAV emissions into the atmosphere can be controlled and uncontrolled .

In the case of emissions of controlled release of SPS is limited to firewalls and usually takes place through regular devices ( flares , pipes , etc.) .

Fugitive emissions are characterized by partial or complete destruction of the process equipment , protection systems, tank shells . They may be accompanied by fires and explosions of gas and dust-air mixtures is caused by repeated destruction of equipment and damage to adjacent objects. This may cause the following processes:

· Short-term or long-lasting high- SPS emissions into the atmosphere, sometimes to a considerable height ;

· Fires in facilities, causing sublimation , Thermal decomposition and burning SPS ;

· Single or multiple low-temperature gas emissions (vapors) from the reservoir ( storage ) of liquefied gases and volatile liquids SPS ;

When shells fracture pressure vessels conventionally entire evaporation process can be divided into three periods:

· The first period - the rapid , almost instantaneous ( 1 -2 min. ) Evaporation by the difference in vapor pressure in SPS capacity and the partial pressure of the air ( butterfly effect). This process provides the bulk of the vapor SDYAV entering the primary cloud ;

· The second period - unstable evaporation, characterized by a sharp drop in the rate of evaporation ;

· The third period - fixed evaporation. Its duration depending on the type of SPS , and the number of external conditions can be from several hours to several days.

At first liquefied gas emissions in the form of a mist of heavy clouds, which, under the action of gravity sink to the bottom. The cloud at the first stage are distinct , they have a large optical density, and only 2 -3 min. becomes transparent. Low cloud lower than the environment. Given its greater density , the main factor determining the movement of clouds in the area of ​​the accident is the force of gravity. At this stage, the formation and movement of clouds is uncertain . The radius of this zone may reach 0.5 - 1 km.

In the case of the destruction of the shell of the isothermal storage and subsequent spill a lot of SPS in the pan there is only 2 or 3 periods of evaporation. Quantity Islands, rolling in the initial cloud is usually not more than 2 - 5%.