THE IGNITION RISK ASSESSMENT PROCEDURE Author: Mihai Magyari, Ph.D.Eng. INSEMEX PETROSANI ROMANIA...

THE IGNITION RISK ASSESSMENT PROCEDURE

Author: Mihai Magyari, Ph.D.Eng. INSEMEX PETROSANI ROMANIA32-34 G-ral. Vasile Milea Street, Petrosani, Hunedoara county+40 254 541 621; +40 254 541 622; Fax: +40 254 546 277e-mail: [email protected]; http://www.insemex.ro

1. Product description: Performances, service life, configuration

The approaching step (the first step) consists in understanding the operation of equipment and/or components and the kind of substances processed, used or released. For this purpose, an analysis of the operation and conditions of use shall be performed.The intended use has to take into consideration, for example, the following elements: lifecycles of equipment and/or components; deadlines for use, time and space (environment, area); function accurate defining; material selection for manufacturing; performances, service life, configuration description of types of substances to be processed and the processing (work) conditions.


2 Ignition hazard identification

2.1 Explosive atmospheres probability and duration of occurrence indoorAn internal explosive atmosphere will occur only if the concentration of the air/gas, mixtures is above the lower explosive limit. Variations in concentration shall be taken into consideration from the beginning up to the end of the work process. Additional variations in concentration due to process conditions have to also be taken into account. If the concentration resides above the upper explosion limit, the hazards as fires have to be considered too. Occurrence of dangerous explosive atmospheres depends upon the following: flammable substances presence; dispersion degree of the flammable substances (for example gas, vapors, mists, dusts); concentration of flammable substances in air, within the explosive range; the sufficient amount of explosive atmosphere, enough to cause damages or losses by igniting it.


2.2 Ignition sources

This stage has as result a complete list of all ignition hazards of the equipment.

To begin with, it has to be determined which types of ignition sources can be generated. All significant ignition sources that could come into contact with the explosive atmosphere have to be taken into account.

The potential ignition sources have to be examined through an operational identification and the differences have to be separately considered, related to: energy levels (temperature, pressure, electromagnetic field, static electricity discharges); constructional variations; operating conditions or work cycles, including their variations (starting, shutting off, load alternating etc.); environment influence (temperature, pressure, humidity, energy sources etc.); materials features or interdependency (metals, synthetic materials, liquids that may build up static charges etc.);


3. Ignition risk estimation

When estimating the ignition risk, the manufacturer decides the ignition hazard probability of occurrence.

The decision shall be based on the following three cases of distinct situations:normal and faulty operation, that can be reasonably foreseen;frequency of occurrence of perturbation or equipment failure that normally have to be considered (foreseeable faults), andrare incidents.

In order to determine the importance of ignition sources, the properties of the explosion caused by mixtures of air with gas, vapor, mists or dusts shall be considered.

The restriction regarding the explosive atmosphere type shall be included in the operating instructions.

For each case, the particular ignition sources have to be individually considered.


4. Ignition risk assessment

The level of protection relates to the defined categories and the respective requirements. Assessment of the ignition risk results in additional measures to fulfill the equipment protection level EPL.

If preventing the explosive atmosphere is not possible, the prevention and protection measures / the type of protection shall be aproached in the following order:

ensuring the ignition sources cannot exist; ensuring the ignition sources cannot become efficient; preventing the explosive atmosphere from reaching the ignition source; mitigating the effects of an explosion occurred inside the equipment and/or

component at an acceptable level and flame propagation prevention.


5 Purpose and finality

The method aims to quantitatively determine the level of risk on a workplace, based on systemic analysis and assessment of risks of occupational injury. Applying the method results in two documents:

1. WORKPLACE ASSESSMENT DATA SHEET, comprising partial risk levels for each risk factor and the global risk level of the workplace;

2. PREVENTION MEASURES DATA SHEET, containing all the technical and organizing measures provided in the standards, comprising all the technical measures for each individual risk factor.

The workplace data sheet, drawn up this way, constitutes the foundation basis for the occupational injury prevention program, for the analyzed workplace, sector, section or economic agent.


QUOTATION SCALE OF THE GRAVITY AND CONSEQUENCES PROBABILITY OF RISK FACTORS ACTIONS ON THE HUMAN BODY


GRAVITY CLASS

CONSEQUENCE CONSEQUENCE GRAVITY

1 NEGLIGIBLE minor and reversible consequences, with a foreseen work incapacity of up to 3 calendar days (healing without treatment);

2 LOW reversible consequences, with a foreseen work incapacity between 3 and 45 days, requiring medical treatment;

3

MEDIUM reversible consequences, with a foreseen work incapacity between 45 and 180 days, requiring medical treatment and hospitalization;

4 BIG irreversible consequences, with a work capacity diminution of maximum 50 % (IIIrd degree invalidity);

5 SEVERE irreversible consequences, with a work capacity diminution of 50-100 %, with the possibility of self-attendance (IInd degree invalidity);

6 VERY SEVERE irreversible consequences, with a full loss of work capacity and self-attendance ability (Ist degree invalidity)

7 MAXIMAL decease

GRAVITY AND CONSEQUENCES PROBABILITY QUOTATION SCALE


PROBA-BILITY CLASS

EVENT CONSEQUENCE PROBABILITY

1 EXTREMELY RARE consequence probability extremely low: P < 10-1 / year

2 VERY RARE consequence probability very low: 10-1 < P < 5-1 /year

3 RARE consequence probability low: 5-1 < p < 2-1 /year

4 LESS FREQUENT consequence probability medium: 2-1 < P < 1-1 / year

5 FREQUENT consequence probability big: 1-1 / an < P < 1-1 / month

6 VERY FREQUENT consequence probability very big: P > 1-1 / month

RISK ASSESSMENT GRID (COMBINATION BETWEEN CONSEQUENCE GRAVITY AND OCCURENCE PROBABILITY)


PROBABILITY CLASSES

1 2 3 4 5 6

EXTREMELY RARE

VERY RARE RARE LESS FREQUENT FREQUENT VERYFREQUENT

GRAVITY CLASSES P < 10-1 /year P > 10-1 P < 5-1 /year

P < 5-1 /year P < 2-1 /year

P < 2-1 /year P < l-1 / year

P < l-1 / yearP < l-1 / month

P < l-1 / month

CONSEQUENCES

7 MAXIMAL DECES (7,1) (7,2) (7,3) (7,4) (7,5) (7,6)

6 VERY SEVERE INVALIDITYIst degree

(6,1) (6,2) (6,3) (6,4) (6,5) (6,6)

5 SEVERE INVALIDITYIInd degree

(5,1) (5,2) (5,3) (5,4) (5,5) (5,6)

4 BIG INVALIDITYIIIrd degree

(4,1) (4,2) (4,3) (4,4) (4,5) (4,6)

3 MEDIUM TEMPORARY WORK INCAPACITY 45180

days

(3,1) (3,2) (3,3) (3,4) (3,5) (3,6)

2 LOW TEMPORARY WORK INCAPACITY345 days

(2,1) (2,2) (2,3) (2,4) (2,5) (2,6)

1 NEGLIGIBLE (1,1) (1,2) (1,3) (1,4) (1,5) (1,6)

RISK LEVEL / SAFETY LEVEL SCALE


RISK LEVEL GRAVITY - PROBABILITY PAIR SAFETY LEVEL

1 MINIMUM (1,1) (1,2) (1,3) (1,4) (1,5) (1,6) (2,1) 7 MAXIMUM

2 VERY LOW (2,2) (2,3) (2,4) (3,4) (3,2) (4,1) 6 VERY BIG

3 LOW (2,5) (2,6) (3,3) (3,4) (4,2) (5,1) (6,1) (7,1) 5 BIG

4 MEDIUM (3,5) (3,6) (4,3) (4,4) (5,2) (5,3) (6,2) (7,2) 4 MEDIUM

5 BIG (4,5) (4,6) (5,4) (5,5) (6,3) (7,3) 3 LOW

6 VERY BIG (5,6) (6,4) (6,5) (7,4) 2 VERY LOW

7 MAXIMUM (6,6) (7,5) (7,6) 1 MINIMUM

OIL DEPOSIT Located in Piatra Neamt - Identified risk factors


PRODUCTION MEANS

Thermal risk factors

F1. adiabatic compression and shock waves

F2. hot surfaces on overheated machinery during operation

F3. hot flames and gas (cooling liquid jets, greasing overheated surfaces during operation)

F4. mechanically generated sparks

F5. fire hazard

Electric risk factors

F6. electric apparatus

F7. electric stray currents

F8. electrocution through direct touch

F9. electrocution through indirect touch

F10. electric safety

F11. static electricity

Dangerous motion, displacement under effect of

gravity or propulsion

F12. non-operation of monitoring or shut off devices, in case of emergency

F13. incorrect operation of safety valves

F14. flammable liquid jets by sealings or pipes ceasing work

F15. driving or crushing into/by the machinery parts in motion during operation

F16. sliding on elements covered with ice, hoar frost



OPE-RATOR

FAULTY ACTIONS

Dangerous surfaces or edges

F17. various parts with sharp edges, rough, handled during operation or repairs

Erroneous actions. Faulty execution of

procedures

F18. unloading parts, sub-assemblies from the machinery platform by dragging and throwing theme down

F19. remedying faulty sealings during installation operation

F20. dropping parts, sub-assemblies handled on the upper part for the installation

F21. falling down from the work platform or access ladder

F22. falling down of the sub-assembly that was working on, being installed in an unstable position

F23. interventions on parts in motion during operation

F24. manual handling of heavy parts

Non-synchronization in procedures

F25. non-synchronizing movement when bringing into the required position at sub-assembly mounting

F26. transportation, manual handling of heavy machinery together with another person

Performing of procedures not

comprised in the work task

F27. personnel stationary remained in the area of where machinery maneuvers take place

F28. attempts of remedying the fault occurred in the electric supply installation of technical equipment



Faulty actions

Communica-tion generating

accidents

F29. putting into motion or hitting parts of the machinery it's been working on, without informing the other operators

Omissions

F30. not blocking on the shut off position the starting operation commands before beginning the intervention

F31. tools, parts left spread out in the working area during repairs

F32. not making use of the personal protective equipment during work in installation

F33. performing works at high height without proper personal protective equipment

WORK TASK

Improper work methods,

wrong succession of procedures

F34. making use of faulty tools, not calibrated or having defective handlesF35. making use of improvised levers to bring parts into the mounting position

Physical stress

F36. effort in dynamic regime submitted when manually handling heavy parts

F37. effort in dynamic regime submitted when working in forced, inconvenient or uncomfortable positions



WORK ENVIRON-MENT

Physical risk, electric

(meteorological discharges)

F38. multiple traumas induced by the explosion caused by a lightning

F39. electrocution as consequence of high voltages induced by atmospheric discharges

Physical risk factors

(temperature, air currents, etc.)

F40. shock, caloric collapse endured when exposed to extreme temperatures, over +35°C in the summer or -20° C in the winter

Physical risk

F41. radiofrequency electromagnetic waves (RF)

F42. electromagnetic waves between 3×1011 Hz and 3 × 10l5 Hz

F43. ionizing radiations

F44. ultrasounds

F45. exo-thermal reactions

Chemical riskF46. acute or chronic intoxications induced by accidental or permanent presence of Diesel liquid in the flexible hoses jointing area

WORKPLACE ASSESSMENT DATA SHEET


Economic agent

Sheet no. 1

No. of persons exposed: 3-4

PETROM S.A. - PETROM REFINING&MARKETING BUCUREŞTI

Exposure duration: 4 h / shift

Workplace:Oil deposit located in Piatra Neamţ, str. G-

ral Dăscăleascu nr. 397A, jud. NeamţAssessment team:

Work system component

Identified risk factors

The concrete form of expression of the risk factors

(description, parameters)

Max. foreseeable

consequence

Gravity class

Probability class

Partial risk level

Production means Thermal risk

F1. Adiabatic compression and shock waves in case of adiabatic compression and shock waves, temperatures so high may occur so as to ignite explosive atmospheres.For example in the pressurized pipework of air compressors and their adjacent containers, explosions may occur due to ignition by compression of the mists of lubricating oils. Shock waves may be generated for example in a sudden release of high pressure gas in pipes. In this process, the shock waves propagate towards the low pressure zones with a velocity higher than the speed of sound. When these are diffracted or reflected by the elbow, stranglings, connecting phlanges or closed valves in the pipeworks etc., very high temperatures may be generated.

Decease 7 1 3

F2. Hot surfaces of the overheated machinery during operation,Radiators, heating coiling, friction couplings (for example at vehicles or centrifuge pumps), mobile parts of shaft bearings, sleeves, if these are not sufficiently lubricated, frictions by axis displacement in rotating machines, chemical reactions (for example with lubricating agents and cleaning solvents). They may cause explosions, or burns at hand level.

Decease 7 1 3



Production means

Thermal risk

F3. Hot flames and gas For example welding or cutting droppings - explosions, burning at hand and face levels

Decease 7 3 5

F4. Mechanically generated sparks After friction, impact or abrasion processes (for example polishing); impact involving rust and light metals (Aluminum and Magnesium); incendive sparks when rubbing hard materials with light metals (Titanium, Zirconium) even if rust is absent. They may generate explosions burns at face and hand levels

temporary work interruption 3-45 days

4 1 2

F5. Fire hazard Caused by flammable substances ignition, released in a concentration higher than the UEL (the upper explosion limit). It may cause severe burns or explosions.

Decease 7 2 4

Electric risk

F6. Electric apparatus May generate electric sparks (for example when switching on and off the electric circuits, loose connections, stray currents) and hot surfaces. They may cause explosions, burns at hand and face levels.

Decease 7 3 5

F7. Electric stray currents For example short-circuit at earthing caused by faults in electric circuits, as result of magnetic induction, as result of meteo-electrical discharges, protection against cathodic corrosion. They may cause body wounds.


2 1 1



Electric risk

F8. Electrocution through direct touch Electrocution through direct touch of the non-insulated electric system, as consequence of opening it or electric live equipment damaged

Decease 7 1 3

F9. Electrocution through indirect touchElectrocution through indirect touch of the insulated electric system, as consequence of a faulty protection earthing circuit.

Decease 7 1 3

F10. Electric safety of workers Electric safety of workers is in danger if: -earth connection of electric equipment is interrupted; -electric equipment enclosures are not closed; -workers are not periodically trained on how to use the electric equipment and how to act in case an event should occur

Decease 7 1 3

F11. Static electricity Causes incendive discharges when discharging the conductive charged parts; the charged parts made of non-conductive materials (for example natural and synthetic rubber, synthetic resins, plastics, artificial fibers) may cause brush discharges, or during the high speed separation processes (for example films driven on rollers, driving belts) or by a combination between conductive and non-conductive materials, resulting in propagating brush discharges or cloud discharges. Are considered dangerous from a point of view of static electricity the substances having a resistivity higher than 105 ·cm. The main processes, operations, activities during which static charges may occur are: combustible liquids or solvents conveying with a relatively high velocity through elements or segments of conducts. These may induce multiple traumas as consequence of explosions generated by static electricity discharges.

Decease 7 1 3



Dangerous motion, displacement under effect of gravity or propulsion

F12. Multiple traumas - As consequence of explosions caused by monitoring or emergency shut off devices not working.

Decease 7 1 3

F13. Multiple traumas - As consequence of explosions caused by improper working of the safety valves.

Decease 7 1 3

F14. Traumas - As consequence of spilling petroleum products temporary work interruption 3-45 days

3 2 2

F15. Crushing, fractures, wounds Induced at hand level by machinery parts in motion during operation.

5 1 3

F16.Fractures, contusions Induced as consequence of slipping on elements with ice coating, hoarfrost, belonging of bridges or platforms


3 3 3

Dangerous surfaces or edges

F17 . Cut or stabbed wounds Cut or stabbed wounds at hand level, caused during handling of parts having sharp or pointy edges.


2 5 3

Erroneous actions. Faulty execution of procedures

F18. Fractures, contusions - Induced through crushing, during unloading parts, sub-assemblies, by dragging or throwing down from the machine's platform.

InvalidityIInd degree

5 1 3

F19. Eyes, face, hands injuries, burns by scalding Induced by improper jointing at sealing repairs, during installation operation

InvalidityIIIrd degree

4 2 3

F20. Hitting, crushing traumasTraumas by hitting, crushing on the persons close to the machinery, when parts or sub-assemblies are dropped from the upper part of the installation


2 3 2

F21. Fractures, contusions, wounds Caused by falling down from the work platform or access ladder.


4 2 3

F22. Fractures by crushing, induced by collapsingInduced by the collapse of the sub-assembly it's working on, due to placing it in an unstable position


5 2 4

F23. Fractures at hand level Caused during interventions on parts in motion during operation


4 2 3

F24. Fractures by crushingCaused by dropping down heavy parts when manually handled.


5 2 4



Non-synchronisation in procedures

F25. Fractures, contusions By crushing, at fingers level, due to non-synchronization of movement when bringing sub-assemblies on position for mounting


2 3 2

F26. Fractures by crushingCaused by dropping the part handled together with another person, as consequence of non-synchronization of movement


2 5 3

Performing of procedures not comprised in the work task

F27.Multiple traumas Induced at starting of technical equipment or when interrupting operation, by catching the equipment in the parts in motion of the dynamic machinery.


4 1 2

F28. Electrocution through direct touch produced during unforeseen starting of equipment, during technical repairs

Decease 7 1 3

Communication generating accidents

F29. Crushing, fractures, contusionsAt hand level, these are produced following starting the machinery or hitting a part in the sub-assembly it's been working at, without informing the other operators.


2 4 2

Omissions

F30. Multiple traumas Encumbered by accidental starting of the installation, due to not blocking the starting commands on the shut off position, before intervention occurs


5 1 3

Omissions

F31. Fractures, sprains, contusions by falling downProduced by falling down at the same level, by tripping due to parts or tools left spread out in the working area, during repair works


2 4 2

F32. Burning or inflammation of eyes Caused by not wearing the proper personal protective equipment during work in installation


2 4 2

F33. Multiple trauma by falling from high heightCaused by falling down from a height as consequence of not using the proper personal protective equipment

Decease



Work task

Improper work methods

F34. Contusions, wounds at hand level Due to making use of faulty or not calibrated tools, or having deteriorated handles


2 5 3

F35. Contusions, wounds at limbs levelInduced as consequence of dropping the improvised lever when bringing parts into the mounting position.


2 5 3

Physical stress

F36. Discopathy effort induced in dynamic regime Caused by manual handling of heavy parts


2 5 3

F37. Discopathy effort induced in dynamic regimeCaused when working in forcefully or uncomfortable positions


2 5 3

Physical risk factors, (meteorological

discharges)

F38. Multiple traumas Produced by an explosion caused by lightning

Decease 7 1 3

F39. Electrocution as consequence of high voltagesInduced in equipment by atmospheric discharges

Decease 7 1 3

Work environment Physical risk factors

(temperature, air currents, etc.)

F40. Shock, caloric collapse, chilblain Induced during operations with exposure to extreme temperatures, over +35° C in the summer or -20° C in the winter


2 5 3



Work Environ-

ment Physical risk

F41. Radio frequency electromagnetic waves (RF) Emitted by radio-transmitters, RF industrial or medical generators for heating, drying, hardening, welding, cutting etc.All conductive parts placed in the radiation field operate as receiving antennas. If this field is strong enough and the receiving antenna large enough, these conductive parts may cause ignition of explosive atmospheres.

Decease 7 1 3

F42. Electromagnetic waves between 3 x 1011 Hz and 3 × 1015 HzIn this spectrum range, the radiation especially if focused may become an ignition source by absorption into solid surfaces (for example sun beams that pass through glass, spotlights).For laser radiations (for example communications, measurements, topography) even at long distances, the power or energy density even for a non focused fascicle, can be that high as to induce an ignition.

NA

F43. Ionizing radiation Generated by, for example, tubes with X-rays and radioactive substances can ignite explosive atmospheres as result of energy absorption. The ionizing radiation may generate an explosive atmosphere as a result of energy absorption. The ionizing radiations may generate an explosive atmosphere by decomposition (for example a mixture of oxygen and hydrogen by water radiolysis)

NA

F44. Ultrasounds A great part of the energy released by the electro-acoustical transducer is absorbed by solid or liquid substances, thus heating so as in extreme cases an ignition may occur

NA

F45. Exothermal reactions - May act as ignition sources in conditions when heat generation rate surpasses the heat loss rate to the environment. Reaching a high temperature in a (exothermal) reaction depends, among other parameters, on the volume/surface ratio in the system that reacts, on the ambient temperature and retaining time. For example, reactions of alkaline metals with water; polymerization reaction a.s.o. In some combinations of construction materials and chemical substances (for example Copper with Acetylene, heavy metals with hydrogen peroxide) violent reactions may occur, that can lead to ignition

Decease 7 1 3

Chemical risk (gas,

vapor)

F46. Acute or chronic intoxications induced by an accidental or continuous presence of Diesel fuel leaks in the joining area or flexible hoses

Decease 7 1 3



The global risk level of the analyzed workplace is the following:

Nr = 3,14

14,3

11283284452

111228332844455243

1

43

1

r

ii

iii

r

N

r

RrN

PREVENTION MEASURES DATA SHEET


Crt. no.

Risc factorRisk level

Proposed measure

Proposed measure nominalizationCompetencies / responsibilities

Deadline

1 Adiabatic compression and shock waves

3 The processes that could generate compression or shock waves should be avoided. In general dangerous compressions and shock waves can be avoided if, for example, guiding and valves within the system with high compression coefficients should be only slowly opened.

EmployerWorkers

At commissioning and permanently

2 Hot surfaces of overheated machinery during operation

3 The temperature class of electric equipment should be than the temperature class of the area where it works.The maximum surface temperature of technical machinery which may come into contact with the explosive atmosphere should not surpass 80% of the minimum ignition temperature of gas or liquid, in °C, during normal operation and in case of rare malfunction.

Employer At commissioning and permanently

3 Hot flames and gas 5 The welding works with open fire or the metal cutting works are allowed in areas with explosion hazard only based on a special work permit issued for that specific work and only after special protective measures had been adopted in order to avoid any danger.


4 Mechanically generated sparks

2 Equipment, protective systems and components which even in case of rare malfunctions may generate incendive rubbing or abrasion sparks shall be excluded. Particularly should be excluded friction between Aluminum or Magnesium (excluding here alloys containing less than 10%Aluminum and paints and coatings with less than 25% Aluminum in mass) and iron or steel (except stainless steel). Friction between Titanium or Zirconium and any hard material shall be also avoided.


5 Fire hazard 4 The fire protection and safety installations (PSI) as moto-pumps, electro-pumps, water cannon, for fire extinguishing, PSI pickets, fire extinguishers and other devices for fire extinguishing, should be maintained in a good working state and periodically checked according to the regulations in force. The fire extinguishing devices have to be signalized according to the Government Decision no. 971 / 2006 (Annex 2 clause 3.5). The storage facility workers have to be trained for interventions should a fire occur. The company shall provide a plan for cases of emergency or major incidents, detailed with measures and attributions for each storage facility in part.

Employer Permanently


Fig.2 - PARTIAL RISK LEVELS ON RISK FACTORS, Work place: Oil deposit Piatra NeamtGLOBAL RISK LEVEL: 3,14

Partial risk levels on risk factors

0

1

2

3

4

5

6

Risk factors

Par

tial

ris

k le

vels


Fig.3 - DISTRIBUTION OF IDENTIFIED RISK FACTORS ACCORDING TO WORK SYSTEM ELEMENTSWork place: Oil deposit Piatra Neamt

GLOBAL RISK LEVEL: 3,14

Weight factor of the risk factors identified according to the work system elements

20.37%

27.79%9.25%

42.59%

Risk factors in work environment

Risk factors in production means

Risk factors in work task

Risk factors of the operator

Thanks for your attention !


THE IGNITION RISK ASSESSMENT PROCEDURE Author: Mihai Magyari, Ph.D.Eng. INSEMEX PETROSANI ROMANIA...

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Transcript of THE IGNITION RISK ASSESSMENT PROCEDURE Author: Mihai Magyari, Ph.D.Eng. INSEMEX PETROSANI ROMANIA...