Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.

Hazard analysis(ppt)

37 798 vues

Publié le

  • Identifiez-vous pour voir les commentaires

Hazard analysis(ppt)

  1. 1. Occupational Safety and Health (KAS3501) Semester 6 2014/ 2015 Group 8 Presentation Date: 1 April 2015 1) SITI FAZLIN BINTI MAT RIFIN UK29516 2) SITI SYAFIQAH BINTI NORHAN UK29517 3) NURAKMAL HIDAYAH BINTI MD YUSOF UK29518 4) MUHAMMAD HELMI BIN SAPERI UK29519 5) LEE WAI YIN UK29538
  2. 2. Title : Hazard Analysis (HAZAN)
  3. 3. What is hazard?
  4. 4. Hazard is the potential for harm. A hazard is often associated with a condition or activity that can cause undesired consequences such as injury or illness if left uncontrolled. Basically, a hazard can cause harm or adverse health effects to individuals or to organizations as property or equipment losses.
  5. 5. Types of hazard
  6. 6. 1) Chemical hazards Chemicals can affect skin by contact. Chemicals can also enter our body either through the inhalation or digestive system if air is contaminated with chemicals, vapor, mist or dust. The accumulation of chemicals in or on our body will cause acute (immediate) effect or chronic (long-term) effect.
  7. 7. 2) Physical hazards Physical hazard will cause injury risks on our body. This category includes the hazards from working in confined spaces, being hit by flying objects, caught in explosions, hurt by collapsing machinery, falling from heights and tripping on obstacles.
  8. 8. 3) Biological hazards (biohazards) Biohazards refer to biological substances that pose a harm to the health of living organisms. Sources of biological hazards may include insects, bacteria, fungi, plants, worms, animals and viruses. These sources can cause a variety of health effects ranging from skin irritation and allergies to infections, cancer and so on.
  9. 9. 4) Ergonomic hazards Ergonomic hazards refer to workplace conditions that pose the risk of injury to the musculoskeletal system of the worker. These injuries can be caused by performing repetitive and forceful movements and awkward postures that arise from improper work methods and improperly designed workstations, tools, and equipment.
  10. 10. 5) Noise hazards Excessive noise can disrupt concentration, interfere with communication and result in loss of hearing. High impact noises are particularly damaging. Noise can also mask out signals and affecting communication with others.
  11. 11. What is Hazard Analysis?
  12. 12. Hazard Analysis Analysing their potential causes First step in a process used to assess risk Result of a hazard analysis is the identification of different type of hazards Process of recognizing hazards that may arise from a system or its environment
  13. 13. Job Hazard Analysis Technique that focuses on job tasks as a way to identify hazards before they occur Identify hazards potentially created by a product, process or application Technique to identify the dangers of specific tasks in order to reduce the risk of injury to workers. Focuses on the relationshi p between the worker, the task, the tools, and the work environment
  14. 14. Determine the hazards and hazardous events of the equipment under control and the control system Analyse the event sequences leading to the hazardous events identified To analyse the risk associated with the hazardous events Identify hazards Identify causes Determine risks Hazard Analysis Objective s
  15. 15. Why Hazard Analysis important?
  16. 16. Importance / Benefit To train workers how to do their jobs safely Policies and procedure improved investigate accidents Increase quality Decrease injury rate.
  17. 17. identify what personal protective equipment Hearing protection Body protection Eye protection Foot protection Material handling aids Hand protection Respirator y protection
  18. 18. Hazard Analysis Procedure
  19. 19. Examine the job and determine the components Identify tasks likely to present hazards Identify and assess hazards Determine and devise controls measures Develop safe work procedures if hazards cannot be eliminated
  20. 20. How to identify and analyze hazard?
  21. 21. Identifying The Hazards  Identify the hazards of each step. For each hazard, ask: What can go wrong? What are the consequences? How could it arise? What are other contributing factors? How likely is it that the hazard will occur?
  23. 23. Hazard may be realized or unrealized Realized hazard – has happened in the past and can therefore be identified from experience. Unrealized hazard – is a potential for a hazardous situation that has not happened yet but can be recognized by analyzing the characteristic of an environment or failure modes of equipment item.
  24. 24. Hazard analysis methods include : Process Hazard Analysis Event Tree Analysis Failure Modes And Effect Analysis Fault Tree Analysis Cause-consequence Diagram Hazard And Operability Studies
  25. 25. 1) PROCESS HAZARD ANALYSIS A systematic method designed to identify and analyze hazards associated with the processing or handling of highly hazardous material PHA analyzes -The potential causes and consequences of fires, explosions and releases of toxic chemicals - the equipment, instrumentation, human actions and other factors which might affect the process.
  26. 26. The Most Hazardous Processes Are First -Most hazardous processes must evaluated first -All PHA must completed as soon as possible - PHA must be updated at least every five years
  27. 27. 2) Event Tree Analysis (ETA) ETA defines the consequential events which flow from the primary ‘initiating’ event. Event trees are used to investigate the consequences of loss-making events in order to find ways of mitigating rather than preventing losses.
  28. 28. 3) Failure modes and effect analysis (FMEA) To identify which failures in a system can lead to undesirable situation. Particularly suited to electrical and mechanical processes. Result are strongly dependent on analyst’s understanding of the failure modes Effects of failure modes can be quantified
  29. 29. 4) Fault tree analysis (FTA) To evaluate the economic justification for carrying out improvement to a system FTA works back from the undesired or “top event” to the contributing causes(backward reasoning logic techniques) To identify the causes of top event
  30. 30. Example of FTA
  31. 31. 5) Cause-Consequence analysis (CCA) Is proving to be a very useful tool to depict and maintain an up-to date, real- time working risk management system enthralled in daily operations (e.g. operational). These diagrams combine the inductive and deductive reasoning of logical diagrams (e.g. ETA, FTA) to identify the basic causes and consequences of potential accidents.
  32. 32. Example of CCA
  33. 33. 6) Hazard and Operability Study (HAZOP) A structured and systematic method that identifies equipment that is being used in a way that it was not designed to be, and which might create hazards and operational problems. HAZOPs are usually conducted by multi- skilled team that studies piping and instrument diagrams. Each pipeline and vessel is evaluated for certain limitations and deviations in flow, temperature, pressure, etc.
  34. 34. How to control hazard?
  35. 35. Controlling the Hazards The order of precedence and effectiveness of hazard control is the following: 1. Engineering controls. 2. Administrative controls. 3. Personal protective equipment.
  36. 36. 1) Engineering Controls Engineering controls include the following: Elimination/minimization of the hazard Substitution of equipment or process to decrease hazard Isolation of the hazard with interlocks, machine guards, blast shields, or other means; and Removal or redirection of the hazard such as with local and exhaust ventilation.
  37. 37. 2) Administrative Controls Administrative controls include the following: Written operating procedures, work permits, and safe work practices; Exposure time limitations (used most commonly to control heat stress and ergonomic hazards); Monitoring the use of highly hazardous materials; Alarms, signs, and warnings; Buddy system; and training
  38. 38. 3) Personal Protective Equipment (PPE)  Personal Protective Equipment is acceptable as a control method in the following circumstances: When engineering controls are not feasible or do not totally eliminate the hazard; While engineering controls are being developed; When safe work practices do not provide sufficient additional protection; and During emergencies when engineering controls may not be feasible.
  39. 39. Case Study of Hazard Analysis Fire at Formosa Plastic Corporation: Evaluating Process Hazard
  40. 40. INTRODUCTION This case study describes a fire and series of explosions in an olefins production unit located in Point Comfort, Texas due to hydrocarbon release. 16 employees were injured and 1 seriously injured. The fire burned for 5 days.
  41. 41.  At 3:05 PM on October 6, 2005, a trailer being towed by a forklift snagged and pulled a small drain valve of a liquid propylene system.  Vaporized propylene forming a large flammable vapor liquid.  Operators began to shut the plant down and attempt to isolate the leak. But, the attempt was a failed.  At 3:07 PM, the vapor ignited and create an explosion. As a result, two operators were burned and fire reached more than 500 ft in air as shown in figure 1.  The fires burned for five days and about 7 million gallons of water were used to cool vessel. INCIDENT DESCRIPTION
  42. 42. Figure 1: Point Comfort Fire
  43. 43. At 9:00 PM, Highway 35 that run adjacent to the Formosa complex and through Point Comfort was closed. A shelter-in-place was provided for the Point Comfort community. It was recorded about 20 local residents need medical evaluation at local hospitals. Figure 2 shows the view of the damaged plant from Highway 35. Figure 3 shows the Olefin II unit ( one of the 17 units) which the fire and explosion occurred.
  44. 44. Figure 2 : View of the Damaged Plant from Highway 35
  45. 45. Figure 3 : Olefin II units
  46. 46. INCIDENT SEQUENCE A worker driving a forklift towing a trailer under a pipe rack moving backward between two column to turn around. When the worker drove forward, the trailer caught on a valve and stick out a strainer in propylene piping system. The trailer pulled the valve and associated pipe (Figure 4) out of the strainer and leaving 1.9 inch diameter opening. Pressurized liquid propylene rapidly escaped through the opening and partially vaporized creating both of propylene liquid and rapidly expanding vapor cloud.
  47. 47. The forklift driver and other contractors saw the release and evacuated. An operator heard and saw the release and notified the control room. The operators closed control valves and began to shut down the unit as well as pump from motor control center to slow the leak as he saw the vapor cloud. The vapor cloud ignited and operators left the unit and declared a site-wide emergency. A large pool fire burned under the pipe rack. The Formosa ERT arrived and took command of the incident response. The fire was extinguished about 5 days.
  48. 48. CAUSES OF INCIDENT Figure 6 shows the propylene piping involved in this incident stick out into an open space and no impact protection. Figure 7 shows passive fire protection was installed on only three of four support column rows and the columns that supported the pressure relief valves and emergency vent piping had no fireproofing.
  49. 49. PROCESS HAZARD ANALYSIS Figure 8 shows the protection of fire fighting equipment. Figure 9 shows the lack of protection where the impact and release occurred. Remote equipment isolation is done by the operators by isolating minor leaks with local valves.
  50. 50. Figure 8 : Protection of Fire Fighting Equipment
  51. 51. Figure 9 : Vehicle Impact Point
  52. 52. LESSONS LEARNED When performing a hazard analysis, facility sitting analysis or pre-startup safety review, vehicle impact and remote isolation catastrophic releases should be investigated. The use of flame resistant clothing may limit the severity of injury to employees who work in plants with large inventories of flammable gases and liquids. Evaluate the applicability and use of current safety standards when designing and constructing a chemical process plant.
  53. 53. References Fire at Formosa Plastics Corporation:. Case study, Washington: CSB publications, 2006. Hazard Analysis Methodologies. https://www.osha.gov/SLTC/etools/safetyh ealth/mod4_tools_methodologies.html (accessed March 27, 2015). Job Hazard Analysis. 2002. https://www.osha.gov/Publications/osha30 71.html (accessed March 26, 2015). Types of Hazards. http://students.fortresslearning.com.au/del 301/types-of-hazards/ (accessed March 23, 2015).