Presentation on theme: "Hazard management in Power Sector: Techniques for Hazard Identification & Risk Mitigation By Dr. Rohit Verma Dy.Director NPTI Dr. Manisha Rani Fellow,NPTI."— Presentation transcript:
Hazard management in Power Sector: Techniques for Hazard Identification & Risk Mitigation By Dr. Rohit Verma Dy.Director NPTI Dr. Manisha Rani Fellow,NPTI
DEFINATIONS HAZARD Source or situation with a potential for harm in term of injury or ill health, damage to property, damage to workplace environment, or combination of these.
HAZARD IDENTIFICATION Process of recognizing that a hazard exists and defining its characteristic
RISK Combination of likelihood & consequences of a specified hazardous event
RISK ASSESSMENT Overall process of estimating the magnitude of risk and deciding weather or not the risk is tolerable
ACCIDENT Unplanned & unexpected event which results into injury or property damage is known as accident.
C AUSES OF ACCIDENTS Unsafe conditions unsuitable clothing for a particular job untidy work area tools in poor condition poor lighting in work area Unsafe act using equipment without having received proper training in its use failing to use the appropriate protective equipment distracting others from their work or allowing yourself to be distracted using tools or equipment incorrectly.
T YPES O F O CCUPATIONAL H AZARDS ·Physical hazards ·Chemical hazards ·Biological hazards ·Mechanical / Electrical hazards ·Psychosocial hazards
T YPES O F O CCUPATIONAL H AZARDS Physical hazards Heat Cold Light Vibration Radiation Noise Chemical Biological Mechanical-electrical Psychological
P HYSICAL H AZARDS HEAT The direct effects of heat exposure are Heat exhaustion heat stroke [civil works] Burns [boiler area, electrical flash over] Heat cramp [civil works, boiler area] COLD [[[[[[ Important hazards associated with cold work Frost bite Chilblains Immersion foot General hypothermia as a result of cutaneous vasoconstriction
P HYSICAL H AZARDS HEAT- As a hazard in power stations can cause 1. Heat stress-it is the aggregate of environmental & physical work factor i.e. Total heat imposed on the body. 2. Heat strain- it is the physiological responses to the heat stress. 3. Heat disorders-these result in heat cramps, heat exhaustion, heat stroke. 4. Heat cramps: painful intermittent spasms of voluntary muscles after hard physical work in hot environment. Cramps usually occur after heavy sweating. 5. Heat exhaustion: profuse sweating, weakness, rapid pulse, dizziness, nausea & headache. Skin is cool/pale. Body temperature is normal, nausea, vomiting and unconsciousness may occur.
Light as a hazard in working condition can be due to: Less lighted areas when the light is insufficient person strains his eyes to see the work object/area. Light requirements are increasing with age of a person to see and work on the object. Excessive light- it is dangerous for eyes when light in work area is excessive since it causes glare. Physical Hazards
LIGHT Effect of poor illuminations are :- Headache Eye pain Lachrymation Congestion around the cornea Eye strain Eye fatigue Exposure to excessive brightness is associated with discomfort, visual fatigue, blurring of vision and may lead to accidents. Physical Hazards
VIBRATION V IBRATION ESPECIALLY IN THE FREQUENCY OF 10 TO 500 H Z, CAN AFFECT HAND AND ARM AFTER MONTH OF YEARS OF EXPOSURE Ill effects: The fine blood vessel of finger becomes increasingly sensitive to spasm (white fingers). Injuries of the joints, of the hands elbow and shoulders may take place Physical Hazards
Hearing impairment due to Noise is, as per the schedule of the Factories act, is reportable as well as compensable. Hearing loss in most cases is not sudden but increases with the length of the work time in the noisy zone. Physical Hazards NOISE Industrial noise can give rise to deafness Non auditory effects are irritation, nervousness, annoyance, fatigue, inefficiency etc.
Threshold Limit Value for noisy working conditions: (An 8 hour shift in all following cases) 8 hours work – 90 dBA 4 hours working – 95 dBA 2 hours working – 100 dBA 1 hour working – 105 dBA half hour work – 110 dBA Threshold of hearing – 125 dBA Sudden deafness/rupture of ear drum can occur at 140 dBA Physical Hazards NOISE
RADIATION A. U LTRAVIOLET R ADIATION HAZARD - S EEN IN WORK WITH ARC WELDING AND MAINLY AFFECTS THE EYES. E XPOSURE TO SUCH RADIATION MAY LEAD TO C ONJUNCTIVITIS AND K ERATITIS (W ELDER ’ S FLASH ) B. I ONIZING RADIATION HAZARDS [X ROOM USG CT] A NEMIA L EUKEMIA C ANCER S TERILITY F ETAL M ALFORMATION IN CASE OF PREGNANCY U LCERATION I N EXTREME CASES DEATH CAN TAKE PLACE Physical Hazards
M ECHANICAL / E LECTRICAL H AZARDS Accident Fall Injury Electricity burn Electric shock.
E LECTRICAL H AZARDS Injury from direct contact 1. Injury by shock 2. Injury from internal burns Injury without current flow through body 1. Direct burns from electrical arcs 2. Radiation burns from very heavy arcs 3. Injury from fire & explosion from electrical arc 4. Physical injury from false starting of machinery, failure of controls 5. Eye injury from electrical arc welding
C HEMICAL H AZARDS Chemical hazards – liquid and gaseous hazards 1. Dust 2. Smoke 3. Fumes 4. Poisonous gases 5. Acids 6. Alkalis
C HEMICAL H AZARDS They enter our body through Skin Inhalation Mouth They can cause internal as well external injuries Skin diseases Lung diseases Internal blood and other diseases
B IOLOGICAL H AZARDS Exposure to infective and parasitic agents Inset bite Dog bite Snake bite
P SYCHOSOCIAL H AZARDS FACTORS - Maladjustment with work environment. Lack of job satisfaction Insecurity Emotional tension Poor human relationships Health problems Fatigue Headache Hypertension Heart disease Peptic ulcer Behaviors changes Anxiety/Depression Sickness absentees
M ECHANICAL H AZARD PREVENTION Preventive maintenance Adequate job training Ensuring safe working environments Establishment of safety department with qualified safety engineer Periodic survey for finding out hazards Application of ergonomics
Noise can be controlled by; 1. Reducing vibrations 2. Enclosing the noise producing equipment 3. Enclosing the operator 4. Moving away from the noisy area 5. Use of personal protective equipments Physical Hazards NOISE
Effective temperature and heat effect in an environment can be controlled by: Increasing air changes Reducing radiated heat by insulation Reflection of heat Drinking plenty of water and intake of salt Use of personal protective equipments Physical Hazards
Continuous working should be avoided and rest pauses after some time of work must be allowed to workers. The driving force of vibrating surfaces may be reduced by; 1. Reducing the forces 2. Minimizing rotational speed 3. Isolating The response of vibrating surfaces may be reduced by 1. Damping 2. Additional 3. Increasing mass of vibrating surfaces 4. Changing size to change resonance frequency Physical Hazards VIBRATION
M ECHANICAL H AZARDS MACINERY HAZARDS: These are due to revolving parts of the machines. These can be controlled by providing machine guards which are a statutory requirements under Sections 21 to 26 of the Factories Act As per section 21 of the Factories Act- provide guards at following; Moving parts of the machinery including fly wheels Transmission machinery Point of operation Any other dangerous part
SAFETY OF MAINTENANCE PERSONNEL Safety precautions are required to safe guard the maintenance personnel from getting involved in machinery accidents owing to inadvertent starting of machinery by; Design of control switches Safe guards for the operating levers Interlocking of power system Mechanical Hazards
PREVENTION Physical hazards Application of ergonomics Maintenance of temperature- 69 to 80 deg. F is the comfortable zone Proper ventilation Good housekeeping Proper illumination Personal protection Personal hygiene Health education Job rotation Periodic health Check up
PREVENTION Personal Protection Post Control Biological Hazards
PREVENTION Good induction program. Management by participation. Establishment of Proper communication channel. Establishment of Healthy personnel policies Establishment of healthy HR relationship. Regular stress management program. Psychosocial Hazards
Chemical Safety There are thousnands of chemical compounds, which presents some form of hazards either major or minor incidents usually termed as chemical accidents. To avoid chemical accidents some points to be kept in mind. 1. knowledge of chemicals 2. knowledge of pocessing plant 3. knowledge of operator C HEMICAL H AZARDS
C HEMICAL H AZARDS IN POWER PLANT Coal/silica dust is major health hazard in power station These dusts enter our body through inhalation Respirable dust particles can enter our lung sacks and reduce our breathing capacity since this reparable dust settles there, Normally coal dust particle less than 1 micron only can enter in our lung sacks. Bigger dust particles either remain in our nose or get stuck in throat. Then they go into stomach and get removed from our body system in natural way. Coal dust is non toxic and as such no effects are caused on body due to the particles of dust in stomach.
C HEMICAL H AZARDS Respirable dust particle which enter into our lungs can not be removed and they remain settled there. Disease which can occur due to inhalation of coal dust is known as “pneumoconiosis” and is irreversible till person is shifted from job Silica dust can cause “silicosis” Both are reportable as well as compensable diseases under the schedule of the factories act
C HEMICAL H AZARDS Control of coal dust by Reduction of dust emission by suppression by wetting coal in wagons, at the time of tippling, water spray in coal conveyors. Suction of coal dust from environment in above areas. Use of personal protective equipments like filter respirators which can filter out reparable coal dust particles. Continuous monitoring of environment by measuring and keeping it below.
2. Gases Gases are the common hazards in many industries leads to suffocation and asphyxia. Asphyxiating gases are – CO, Cyanide, SO 2, Chlorine etc. Chemical Hazards Smoke: inhalation of smoke which can contain poisonous gaseous fumes also and can have effects on our health; Fumes: fumes emanating from liquid chemicals can cause ill effects on our health when inhaled; Vapor: vapors of chemicals liquids are also dangerous to our health when inhaled. Vapours of hydrazine hydrate can cause unconsciousness when inhaled.
3.Metals and compounds Toxic hazards are seen from Lead, Mercury, Chromium, Arsenic etc 4.Chemicals Acid (water treatment/ chemistry), Alkali and Pesticides. Chemical Hazards Hazardous chemicals used in thermal power stations: Chlorine Hydrochloric acid Euphoric acid Hydrazine hydrate Liquor ammonia Sodium hydroxide
C HEMICAL H AZARDS It is the most hazardous chemical used It is used in water treatment plant It is procured in toners for use in chlorinationation When more than 10 tons of chlorine is stored/ handled/used in any industry, a Disaster Management Plan (DMP) is required to be prepared and submitted to statutory authorities. This DMP is required to be practiced through mock drills periodically and review meeting are to be conducted for checking discrepancies. Chlorine
C HEMICAL H AZARDS Chlorine vapor is poisonous when inhaled Will cause burn in eyes Chlorine liquid can cause burn on skin and eyes Threshold Limit Value (TLV) for chlorine is 1 ppm At 100 ppm it can be fatal. Chlorine
P LANT / SECTIONS WHICH ARE PRONE TO EMERGENCIES 1. Coal handling plant 2. Main plant 3. Water treatment plant 4. Hydrogen generation plant 5. Mgr transpiration system
P REVENTION OF C HEMICAL H AZARD (P NEUMOCONIOSIS ) 1.Dust control- ·Proper Ventilation ·Exhaust ·Enclosed apparatus ·Good house keeping 2.Personnel protection ·Mask, clothing, cloves, apron, boots barrier cream etc 3.Personal hygiene 4.Health education about respiratory evolvement and personal protection 5.Medical control Periodic medical check up for early detection 6. Bagasse control- ·Spraying with 2% propionic acid- ·Keep the moisture content around 20%
Fire hazard Fire is a chemical reaction or series of chemical reaction accomplished by heat, light, smoke or other gases.
F IRE H AZARDS I N P OWER P LANTS Coal handling plant: coal dust accumulation on conveyor decks, cable trays, head & tail pulleys, jamming of idlers and pulleys, belt sway, belt tension, dust & coal deposited at tops, crusher house and vibrating scene floors, bunker house, failure of belt joints, snapping of belts, partially damaged belt in operation, smoldering fire in bunkers
F IRE H AZARDS I N P OWER P LANTS Cables in cable galleries and on trays in all plant sections, coal dust deposited on cable trays in mill area Fuel oil handling and oil tanks (hsd,hfo,lshs, naphtha, petrol, diesel oil ) Transformer oil, turbine oil, control fluid, seal oil, Natural gas Electrical system Heat path damaged insulation Grass Accumulation of waste material etc.
E XPLOSION H AZARD I N P OWER P LANT Hydrogen plant Turbo generators where hydrogen is used for cooling of Generator. Boilers
Safety audit A systematic & independent examination of all or part of a total operating system to determine whether safety activities comply with planned arrangements for ensuring safety and health of workers and other interested parties who may be affected and whether these arrangements are effective and are suitable to achieve objectives. Hazard Identification Techniques
Safety survey Safety survey is a detailed & in-depth examination of a narrow field of activity eg... Major key areas revealed by safety audit, Individual plants, Procedures or A specific problem. Hazard Identification Techniques
Safety inspection A routine scheduled inspection of a department or unit which may be carried out by personnel within the unit. During inspection deviations from safety standards, employee’s unsafe work practices and unsafe conditions are checked. Hazard Identification Techniques
Safety tour Safety tour is an unscheduled examination of a work area, carried out by any personnel from manager to safety committee members to ensure that company’s safety standards and procedures are being observed. Hazard Identification Techniques
Safety sampling A specific application of safety inspection / tour designed for random sampling of any activity posing serious accident potential. During safety sampling number of defects Are observing for immediate corrective actions. Hazard Identification Techniques
Hazard and operability studies Hazop is essentially a examination procedure takes full description of the process, systematically questioning of every part of process to discover how deviations from the intention of the design can occur and decides whether these deviations can give rise to hazard. Hazard Identification Techniques
Principles of examination Full description of the process, systematically questions on every part of the process Discover deviations from the intention of the design can occur Decides weather these deviations can give rise to Hazards Hazard Identification Techniques
Failure Mode and Effect Analysis (FMEA) Failure or Malfunction of each component is considered Effect or Consequences of failure traced Frequency of Occurrence, Severity of Failure and detecting the problem Impact on the System Functioning is evaluated Remedial method for Possible Impact
Fault Tree Analysis Starts with Undesired event. All possible happenings contributing Undesired event is listed. Put these happenings in the form of tree with logic signals OR and AND.
JOB SAFTEY ANALYSIS (JSA) JSA is a procedure used to review job methods at the design stage itself to ensure safe working at the site places and to adopt the safe working practices. However, it may also be used successfully to uncover hazards that may have developed after production started: or that resulted from change in work procedures. The procedure of job safety analysis is simple and consists of 4 basic steps. a) Jobs with potential for more frequent accidents, b) Severity of injury c) New jobs in which the accident potential is unknown should be selected first from the entire job list. d) Proper Care for analyzing the job condition.
PLANT SAFETY INSPECTION Inspections are that monitoring function conducted in the organization to locate and report existing and potential hazards which have the capacity to cause accidents in the work place. Inspections are not primarily aimed at unearthing new types of hazards; though that may be achieved also; but rather at locating and correcting known hazards. Continuous Inspection Periodic Inspection:
Steps to Control Hazard Step 2. List, rank and set priorities for hazardous jobs - List jobs with hazards that present unacceptable risks, based on those most likely to occur and with the most severe consequences. These jobs should be your first priority for analysis.
Steps to Control Hazard Step 3. Controlling Hazards Solutions to the Control of Hazard are identified and measures are executed Hazard can be eliminated (i) At the Source (ii) Along the path from hazard to the Worker (iii) At the level of the worker
Hazard Removal at the Source 1.Elimination - Getting rid of a hazardous job, tool, process, machine or substance is perhaps the best way of protecting workers. 2.Substitution - Sometimes doing the same work in a less hazardous way is possible. 3.Redesign - Jobs and processes can be reworked to make them safer. 4.Isolation - If a hazard cannot be eliminated or replaced, it can sometimes be isolated, contained or otherwise kept away from workers. 5.Automation - Dangerous processes can be automated or mechanized.
Hazard Removal along the path from Hazard to Worker 1. Barriers - A hazard can be blocked before it reaches workers. Proper equipment guarding will protect workers from contacting moving parts. 2. Absorption - Baffles can block or absorb noise. 3. Dilution - Some hazards can be diluted or dissipated. For example, ventilation systems can dilute toxic gasses before they reach operators.
Hazard Removal at the Level of Worker Work procedures, supervision and training Administrative controls Job rotations and other procedures can reduce the time that workers are exposed to a hazard Housekeeping, repair and maintenance programs Hygiene - Hygiene practices can reduce the risk of toxic materials being absorbed by workers or carried home to their families. Personal protective equipment (PPE) and clothing - This is used when other controls aren’t feasible and where additional protection is needed. Workers must be trained to use and maintain their equipment properly.
R ISK MANAGEMENT Risk Management is the Identification, Analysis and Economic control of those risks which can threaten the assets, human being or earning capacity of an enterprise
S TAGES IN R ISK M ANAGEMENT Identifying the hazards Evaluating the associated risks The likely effect of a hazard may for Example be rated: Major, Serious, Slight- The likelihood of harm may be rated: High, Medium, Low Controlling the risks
C ONTROLLING R ISK Risk Avoidance Risk Retention Risk Transfer Risk Reduction
C ONCLUSIONS The thought process behind selecting hazard evaluation techniques is complex, and a variety of factors can influence the decision-making process. Hazards identification, hazards categorization, and hazards analysis are key components of integrated safety management for facilities and activities in industries. Each hazard evaluation technique has unique strengths and weaknesses. These techniques can provide the industrial hygienist with the tools needed to protect both workers and the community from both major and small-scale hazards. Probability of occurrence of hazard increases the risks associated with an industry. A risk management proposal has been given for the ready reference in this paper.
REFERENCE Ericson, C. (2005). Hazard analysis techniques for system safety. New York: John Wiley and Sons. Leveson, N. (1995). Safeware: System safety and computers. Reading, MA: Addison-Wesley. Mannan, S. (Ed.). (2005). Lees' loss prevention in the process industries. Burlington, MA: Elsevier Butterworth-Heinemann. Manuele, F. (2008). Advanced safety management focusing on ZlO and serious injury prevention. New York: John Wiley and Sons. Suokas, J. (1985, Sept.). On the reliability and validity of safety analysis [Technical Report Publications 25]. Espoo, Finland: Technical Research Center of Finland. Suokas, J. (1988). Evaluation of the quality of safety and risk analysis in the chemical industry. Risk Analysis, 8(4), Suokas, J. & Kakko, R. (1989). On the problems and future of safety and risk analysis. Journal of Hazardous Materials, 21, Suokas, J. & Pyy, P. (1988). Evaluation of the validity of four hazard identification methods with event descriptions [Research Reports 516]. Espoo, Finland: Technical Research Center of Finland. Suokas, J. & Veikko, R. (1989, April). Quality control in safety and risk analysis. Journal of Loss Prevention in Process Industry, 2,