Safety Final PDF

Lecture 1 General Introduction Who is the Engineer? Engineers create products and processes to satisfy the basic needs for food and shelter, and to enhance our everyday livess Innovation is viewed as the application of better solutions through more effective P...

Lecture 1 General Introduction Who is the Engineer? Engineers create products and processes to satisfy the basic needs for food and shelter, and to enhance our everyday livess Innovation is viewed as the application of better solutions through more effective Products, processes, services, technologies, and business models. Innovation is an important part of the engineering process. Human factors engineering and safety engineering are important engineering disciplines. Safety, Definitions. Danger: the negative consequence (or harm) that might be experienced (such as death, injury, illness, etc.) Hazard: a source or cause of danger (i.e. water can cause drowning) Risk: the probability of incurring harm at a certain level of severity Severity: an objective or subjective measure of the harm or negative consequences (such as number of lives lost, money spent on insurance, voter wrath, etc.) An accident is an unintended, unanticipated, and uncontrollable single or multiple event sequence caused by unsafe acts, unsafe conditions, or both AND may result in immediate or delayed undesirable effects Direct Costs of Accidents Indirect Costs of Accidents Medical (doctor visits, physical Reduced productivity therapy, medicine, etc.) Accident investigation Administrative costs Lost time by supervisor Costs of training replacement worker Overtime Legal fees Equipment repair Negative publicity Damage to customer relations Accident: is an unplanned, undesired event that results in personal injury or property damage. Incident: is an unplanned, undesired event that adversely affects completion of a task. 1|Page Major Injury accident: Forklift driver killed when heavy product pushes truck over Minor Injury accident: Forklift hits stack, product strikes employee No Injury Incident (near miss): Forklift hits stack, stack sways Hazard: Forklift operating in a tight aisle Accidents happen due to the inadequate in the safety management in the first place not only the failure in the equipment or installation. The safety management should be improved periodically. How to control safety? Identify hazards. 1. Knowledge and Recognition. 2. Prioritization Maintain an acceptable level of safety through: 1. Hazard elimination 2. Hazard reduction Move from engineering to administrative controls Move from source to path to receiver 3. Hazard communication Evaluate and assess safety program. Why “Safety” Social obligations: Moral and ethical reasons Worker morale Fiscal obligations, money (indirect and direct costs) Outlays Savings Value Legal obligations Laws and regulations Government agencies and authorities Egyptian Labor law OSHA standards and regulations 2|Page Chapter 1&2  Lecture 2 Safety: Fundamental Concepts and Standards As managers deny this responsibility and attempt to leave the decision to employees which results a workplace with a low level of safety. Safety is both management and workers commitment OSHA: Occupational Safety and Health Administration. Workplace Fatalities reduced by more than 67 % Any Accident has Direct costs which are the ones we think of first Indirect costs which are the ones that are less o bvious but they cost more than the direct ones Workers’ compensation Should be according to the degree of injury. Traditional Indexes of measuring accidents: Frequency: number of cases per standard quantity of workhours. (includes only those cases in which the worker missed at least a day of work) Severity: lost workdays per standard quantity of workhours. Seriousness: the ratio of severity to frequency. New Index of measuring accidents: The total injury-illness incidence rate number of injuries and illnesses including fatalities 𝑡𝑜𝑡𝑎𝑙 𝑖𝑛𝑗𝑢𝑟𝑦 − 𝑖𝑙𝑙𝑛𝑒𝑠𝑠 𝑖𝑛𝑐𝑖𝑑𝑒𝑛𝑐𝑒 𝑟𝑎𝑡𝑒 = × 200000 total hours worked by all employees during the period coverd Medical Treatment does not include simple first aid Simple First Aid. Abbreviation Word Definition TRC Total-Recordable-Cases all recordable injury and illness cases, except fatalities LWDI Lost-Workday-case counts injury (excludes illness) cases involving “lost Incidence rate workdays.Fatalities are not included DAFWII Days Away from Work injury and illness cases that involve days away from Injury and Illness case rate work. Fatalities are not included Record Keeping is Important for Safety and health program. (Forms and reports). Safety is the state of being Safe, protected against accidents and it is also the control of hazards Occupational safety: The avoidance of industrial accidents that cause injury and fatality. Occupational Health: avoidance of diseases and disorders induced by exposure to materials or conditions in the workplace Risk is the chance of injury, damage, or loss Risk = Probability * Severity Probability: is Measure of chance of that hazard causing harm. Severity: a measure of the harm. 3|Page  Lecture 3 A Typical Safety Management Program A typical Safety Management Program Includes: I.Management Commitment (TMC) It is how much Time, Money, and Concern the employer gives to the safety II.Effective Accountability Companies Should: Encourage Safety. Require Managers to do safety planning. Provide Employees with adequate training. III.Employee Involvement Individual Motivation. Individual Abilities. Leadership and communication. Heinrich’s 88:10:2 ratio which is Unsafe acts: Unsafe conditions: Unpreventable causes To minimize Hazards One must be able to 1. Recognize hazards 2. Define preventive actions 3. Assign someone to implement preventive actions 4. Provide means for measuring effectiveness IV.Hazard Identification and control. 1. The Four Ms Model A model stating the possible factors of industrial accidents. Man: Related to human mistakes (the direct cause of accidents) It is any act by the human that can reduce the safety or lead to an accident. There are two types of human errors: - Omission errors: Worker fails to take action that is called for. - Commission Errors: Worker takes action, but it is wrong. There is Factors affecting the accident rate due to the human. - Age: Accident rates increase with the young persons and elderly. - Time on job: Accident rate increases in the first three years in job. - Fatigue: reduce Awareness - Stress: reduces available attention resources. (reasons may not be work related) 4|Page  Machine (job factors): anything is used in the operation Accident rates are higher in some industries as they are more dangerous than others. Main job factors: - Methods: May be Manual, mechanized, or automated. (if completely manual that will increase fatigue which will increase the human error and accidents, if completely mechanized the equipment present its own risks of accidents). - Machine: is useful in industry for its ability to apply high forces and power. This ability presents three categories of hazards which is Electrical, mechanical and temperature hazards (Which will be studied later) - Material: Materials that cause hazard is classified into: 1. Corrosive: Acidic substances that can burn human skin 2. Toxic: poisons that disturb the normal body processes. 3. Flammable: Present hazard of fire and explosion. Media: Environmental Factors which is any condition that surrounds the operation Physical Factors as lighting, noise, temperature, humidity, fire and radiation hazards Social Factors as Management polices and practices, Social and culture norms, Training and instruction, safety programs and place. Management: there must be a policy stating the importance of safety, it assigns Responsibility, Authority And accountability. It has an extension called produce for implementation. 2. Domino Theory (Heinrich, 1932) This theory postulates that the events, which lead to an injury, are like five dominos, standing on end, ready to knock each other over in turn. 5|Page  3. Fishbone Diagram (6Ms) Machine Method Man Media 4. Swiss Cheese Diagram V. Accident Analysis/Investigation. Proactive Approach is doing everything to anticipate and prevent accidents. Preventive Actions should focus on Accidents and their causes and less attention should be placed on effects. Experiment 300:29:1 Ratio will help as there is 330 accidents of the same kind. Reactive Approach is doing everything to limit losses after an accident occurs. 6|Page VI. Education and training Knowing all the ways you can get hurt at work, can help you stay safe. VII. Program Evaluation ❖ Incidence Rate how many incidents of a certain kind occurred during a given year 𝑵𝒓𝒄 𝐈𝐑 = 𝟐𝟎𝟎𝟎𝟎𝟎 𝑯𝒋𝒆 ❖ Severity Rates tracks number of lost workdays due to illness or injuries. 𝑵𝒍𝒘𝒅 𝐒𝐑 = 𝟐𝟎𝟎𝟎𝟎𝟎 𝑯𝒋𝒆 ❖ Average Severity 𝑵𝒍𝒘𝒅 𝐀𝐒 = 𝑵𝒓𝒄 ❖ Average Days Away From Work 𝑵𝒍𝒘𝒅 𝐀𝐃𝐀𝐖 = 𝑵𝒄𝒍𝒘𝒅 𝑵𝒓𝒄 = Number of recordable cases during a given period of interest. 𝑯𝒋𝒆 = worker Hours of job exposure during same period. 200,000 is for 100 employees working 2000 hr/year 𝑵𝒍𝒘𝒅 = Number of lost workdays during period of interest. 𝑵𝒄𝒍𝒘𝒅 = Number of cases involving lost workdays. 7|Page  The first and preferable line of defense would be to find some way to eliminate the source of the noise exposure.This might be a process change that results in quieter equipment or it could be the isolation of the equipment in a room where employees are not exposed to the noise hazard. An administrative or work-practice control would be to schedule employees on a rotation basis so that the exposure to the excessive noise would be limited to short durations.This approach might be combined with the engineering approach of isolating the noise source in a separate room, accessed on a short-term basis only when necessary by essential personnel.The last resort should be personal protective equipment or hearing protectors, which depends for its effectiveness upon employee actions to actually wear the protective equipment and wear it properly scaffold components is 4:1. For overhead crane hoists, the factor is 5:1, and for scaffold ropes, the factor is 6:1 additional principles of engineering design that consider the consequences of component failure within the system. These principles are labeled here as fail-safe principles, and three are identified: 1. General fail-safe principle The resulting status of a system, in the event of failure of one of its components, shall be in a safe mode. 2. Fail-safe principle of redundancy 3. Principle of worst case Accident analysis is not used nearly enough to assist in the other approaches to hazard avoidance. The enforcement approach would be much more palatable to the public if the enforcing agency would spend more time analyzing accident histories  Lecture 4 Hazards Categories in Workplace I. Structure collapse/failure Results when structural elements fail. May be Caused by: - Natural phenomena (Earthquakes, tornados or severe storms) - Design and construction defects - Fire or explosion There are two ways of structural collapse: - Explosion: building collapse to the outward direction for any reason. - Implosion: when the walls building is pulled into the center of mass. II. Walk and fall hazard: - Tripping, slipping and falls - Falls result in 15-20% of all accidental deaths and injuries - Slips, trips, and falls make up the majority of general industry accidents - Are second only to motor vehicle crashes - There are three dangerous attitudes that lead to fatal falls: o I do not work very high (25%(30ft)) o I’ll catch myself (6 feet within 0.5 second &16 feet within 1 second.) o I have a good balance (Controlled work conditions) - Common Fall Hazards o Overhead Platforms o Overhead Runways o Elevated Workstations o Floor Openings/Pits o Wall Openings - Fall Hazard Control o First line of defense (Eliminate the fall hazard) - Make the gauge at the ground level - Use drones for inspections at height. Hole covers/grates - Designed to withstand intended load - Secured-bolted, hinged, latched, locked - Authorized person for opening/closing 8|Page  o Second line of defense (Prevent the fall) - Guard Rails Standard railing Top rail, mid rail, and posts Height from upper surface of top rail to floor level is 42” (+/− 3”) Mid-rail height is 21” Standard toe board 3.5” high nchorages Not more than ¼” clearance above the floor - Fences and barricade Prevent unauthorized employee to fall hazard ody harness Protect the authorized person from the fall omponents hazard - Personal Fall Arrest system Used to keep worker from reaching fall hazards Body belt or harness Used when guard rail or hole cover are removed. o Third and last resort (Control the fall) - Positioning Devices - Consists of a body belt and connecting device - Allows the workers to use hands as they don’t need to use it to hold themselves. 1. Unless working on a ladder, scaffold or scissor lift, OSHA requires fall protection when exposed to a 4-foot fall or greater - Safety Net Systems specially designed mesh nets, panels, they are used as protection for those who work 25 ft or more above the lower level. - Employer Requirements ▪ Training - Possible fall hazards in your work - Methods used to protect you from these hazards - Proper and safe use of any hazard prevention systems - Applicable OSHA standards 9|Page  ▪ Inspection - Your employer must inspect the workplace for possible source of hazard and make sure that the fall hazard control systems is applied - You must inspect your positioning and fall control system each use ▪ Rescue - Personal fall arrest system requires a rescue plan. - Employer must communicate the rescue plan to all involved. III. Electrical Hazards ❖ Causes 1. Insufficient insulation. 2. Wetting of the workplace and machine. ❖ Types of electrical injuries Direct: B=burn - Electrocution or death E= electrocution - Electrical Shock S= shock - Burns A= Arc flash/Blast ❖ Factors of how electrical hazard affect the human body. F= fire - Current Flow (the greatest danger to human in electricity) E= explosion - The path taken through the body Duration of the shock - “Freeze current” which is the current results the worker to stick to the electric conductor - “Let-go current” the current at which the person can release his hand ❖ Detection of electrical hazards ❖ How to reduce the electrical Hazards? 1. Use of double insulation 2. Use fuses and circuit breakers 3. Make sure of grounding of machines. 4. Block the areas of exposed energized equipment 5. Pre-plan work, post hazard warnings and use protective measures 6. Keep working and walking spaces clear of cords, cables or wires 7. Training: 10 | P a g e  - Special training is required for authorized people to work on electrical equipment and it covers: - Safe work practices - ONLY authorized People may - Isolation of electrical sources deal with electrical work. - Test Equipment 8. Use of locks and tags - Tools and PPE 9. Electrical Safety Program. In US electrocution accounts for almost 6% of all workplace deaths so an electrical safety program must be applied: 1. Ensure compliance with existing OSHA 2. Provide adequate training. 3. Conduct safety meetings regularly 4. Inspect work sites 5. Encourage all workers to participate in workplace safety. 6. Make hazard analysis to identify potential electrical hazard and safety interventions. Lecture 5 Hazards Categories in Workplace (cont’d) IV. Mechanical Hazard and Machine Safeguarding Mechanical hazards are associated with the power-driven machines, or mechanical devices whether automated or manually operated. Safety and health engineers must have knowledge about what makes a machine dangerous (the hazards caused by this machine) Machine Hazards in order from the more dangerous to the less 1. The point of operation. 2. The power transmission (pulleys and belts) 3. in-running nip point, ingoing nip points occurs In this type of hazards The moving material passes adjacent to or in contact with machine parts. can cause indirectly by catching loose clothing and drawing the worker into the machine. There is many types of mechanical motions and actions as: Rotating (including in-running nip points) Reciprocating Cutting The seriousness of cutting or tearing the skin depends Punching Pinching on how much damage to the skin, and muscles. Shearing : Bending often amputated 11 | P a g e fingers and hands  And Rotation Motion Includes the following mechanisms: Couplings Clutches Cams Mechanical Hazards: 1. Power transmission: 2. Shearing Power-driven shears are widely used in manufacturing with paper, metal, and plastic. Often cause amputated fingers or hands when the worker but his hand under the shearer for adjustment. 3. Crushing Happens between part of the bogy got in between to progressively moving 2 parts in the machine. There are two types of Crushing Hazards: Squeeze-point type Happens when body get in between two parts of the machine and one is in motion. Run-in point type/In-running nip point hazards Happens when body get in between two parts of the machine and one is rotating. 4. Breaking Machines can cause bone breaking and that can be Simple/incomplete : where the bone still one piece but cracked and skin is not effected. Compound/Complete: where the bone is divided into two or more pieces and the surroundings are affected. Safeguarding: Any machine part, function, or process which may cause injury must be safeguarded. The Cause of Danger may be: Direct: Machine Malfunction Indirect: Chips, Chemicals, And hot metal splashes Types of Machine Guarding Systems: - Devices: o Presence sensing o Radio frequency o Photoelectrical (optical) o Electromechanic al 12 | P a g e  - Guards: o Fixed: o Interlocked Can be mechanical Or Electrical. o Adjustable Max Gap Allowable gaps Grinder 13 | P a g e Zero Mechanical State After shutdown energy such as pneumatic or hydraulic pressure, electrically charged capacitors, spring tension or compression, or kinetic energy from flywheel rotation Point of operation Safeguarding that Provides a barrier for an unintended/unplanned contact with the point of operation : Gate Safeguarding system: If the gate does not fully close, machine will not function. Two-Hand Control Requires the worker to constantly press on specific buttons which are a safe distance apart from the danger zone, And the machine will not operate till the 2 buttons are correctly pressed. Safeguarding by Location/Distance Making the control panel in a safe distance away from the operating point which will guarantee worker’s safety of the operation point hazards. Slitter Guarding 14 | P a g e In inches  Machine Safety Responsibilities 1. Management Ensure all machinery is properly guarded. 2. Supervisors ▪ Train employees on specific guard rules in their areas ▪ Ensure machine guards remain in place and are functional. ▪ Immediately correct machine guard deficiencies 3. Employees ▪ Do not remove guards unless machine is locked and tagged. ▪ Report machine guard problems to supervisors immediately ▪ Do not operate equipment unless guards are in place. V. EXTREME TEMPERATURE HAZARDS Controlling temperature, humidity and air distribution is a part of providing safe workplace as the extreme cold or hot can be uncomfortable and dangerous for the workers so the heat stress, cold stress and burns are major concerns of the modern safety and health professionals. Thermal comfort: ▪ Temperature ▪ Air distribution ▪ Humidity ▪ Other Basic concepts 1. Conduction: is the transfer of heat between two bodies that are touching or from one location to another within a body. 2. Convection: is the transfer of heat from one location to another by way of a moving medium (gas or liquid). 3. Metabolic heat: is produced in a body because of activity that burns energy. Heat stress and strain Heat stress: is the net heat load to which a worker may be exposed from the combined contributions of metabolic effect of work, environmental factors, and clothing requirements. Heat strain: is the overall physiological response resulting from heat stress. How to recognize the presence of heat strain? Sustained rapid heart rate (180-age of the worker) Core body temperature (>38.5) Sudden and sever fatigue. 15 | P a g e  Heat stress management Safety and health engineer should ensure that a comprehensive heat stress management program is placed. General controls Provide accurate verbal and written instructions. Training programs Encourage drinking small volumes of cool water every 20 min. Monitor those employees who take medications. Encourage healthy lifestyle. Specific controls Engineering control to provide air movement, and reduce process heat Set the acceptable exposure times (WTT) Personal protective equipment Cold stress Excessive exposure to cold can lead to hypothermia, which can be fatal. Health and safety engineers should prevent the deep body temperature from falling below 36. Excessive exposure to cold stress can result in: Reduced alertness. Poor decision making. Reduced muscular function. Reduced blood flow. Reduced function of the nervous system. Wind speed can majorly reduce the temperature so the air distribution must be but in consideration. How to prevent Cold Stress? Apropriate PPEs including face, head, and ear protection. When wind exists, reduce its effect by wind screen and wind breaking clothes. When the chance of getting wet exists, wear impermeable clothes. Use auxiliary heat applied directly to the hands and feet. Employees should be under continues observation. Do not allow new employees to work full time until they accommodate to the environment. 16 | P a g e  Burns and their effects. Burns are one of the dangers that are caused by heat hazards and they are very dangerous as they cause malfunctional of the skin. 1. First degree: minor and results in mild inflammation of skin (like sunburn) 2. Second degree: easily recognizable due to the blisters that from on the skin (Can be caused by a temperature of 98.9°C) 3. Third Degree: can be fetal, depends on the amount of body affected (caused by steam or hot liquids) Lecture 6 Hazards Categories in Workplace (cont’d) Ergonomics is a multidisciplinary science that studies human physical and psychological VI. Manual Material Handling Issues ❖ Manual Material handling Consideration ▪ Material Manual Handling is a task that almost every worker performs, either as a one-time or infrequent duty or as part of regular work an important application of ergonomic principles that particularly addresses back injury prevention. ▪ Materials Handling Activities: 1. Lifting/Lowering: Raising an object to a higher place, and lowering is the opposite. 2. Pushing/Pulling: Pressing with force to move smth forward, and pulling is opposite. 3. Twisting: The act of rotating the upper body while the lower is relatively fixed. 4. Holding: Holding an object in worker’s grasp while Staying still. 5. Carrying: Holding an object in worker’s grasp while moving. - MMH is a major and common cause of occupational fatigue an low back pain. - About 75% of workers with MMH as a part of their job suffers low back pain. - Back injuries is the cause of about one third of LWD & 40% of compensation costs. - More important than financial loss is the human suffering. ❖ Work Factors Contribute to Back Injury During MMH. 1. Weight of the load lifted: For most workers, weight over 20 kg causes back injury 2. Range of the lift: The preferred range is between knee and waist height. 3. Location of the load to the body: A load lifted from a place away from the body imposes more stress on back. 17 | P a g e  4. Size and shape of the load: Bulky objects is harder to handle than a regular object of the same mass as its center of mass can not be close to the body. 5. Frequency of lifts: Number of lifting times and duration of holding are important factors. 6. Excessive bending and twisting: Poor layout of the workplace also increases the risk for injury. For example: - Shelves those are too deep, too high, or too low causes unnecessary. bending or stretching. - Lack of space to move freely increases the need for twisting and bending - Unsuitable dimensions of benches, tables, and other furniture. - Similar stressful body movements occur where work areas are overcrowded with people or equipment. National Institute for Occupational Safety and Health ❖ Revised NIOSH equation for the design and evaluation of manual lifting tasks - They consider the weight plus several other variables that Affect the risk of injury. - e.g., A situation that requires frequent lifting or the targeted object is far from the body o the worker has a higher risk. In this situation the weight load will be reduced from “LC” -Load constant- to “RWL” Recommended Weight Limit. - “LC” of 23 kg (51lb) was established by NIOSH as a load that is safe for 75% of females and 90% of males. - The recommended weight limit is calculated by using the NIOSH lifting equation. Variables controlling the “RWL.” 1. Horizontal distance (H): The distance load is lifted (distance of hands from midpoint between ankles) 2. Vertical location (V): the starting height of the hands from the ground 3. Vertical distance of lifting (D): e.g., straight in front of you or off to the side 4. Time between lifts or frequency of lifting (F) 5. Angle of the load in relation to the body (A) 6. Quality of the grasp or handhold based on the type of handles available (C) Multipliers in the workplace: 1. HM, the "Horizontal Multiplier" factor AM 2. VM, the "Vertical Multiplier" factor 3. DM, the "Distance Multiplier" factor 4. FM, the "Frequency Multiplier" factor 5. AM, the "Angle Multiplier" factor 6. CM, the "Coupling Multiplier" factor 18 | P a g e  where LC is the load constant (23 kg or 51 Ib) Multipliers in the workplace: 1. HM, the "Horizontal Multiplier" factor In cm - from the midpoint between the ankles to the hands while holding the object. 2. VM, the "Vertical Multiplier" factor In cm - The vertical distance of the hands from the ground at the start of the lift. 3. DM, the "Distance Multiplier" factor The vertical distance (D, in cm) that the load travels. 4. FM, the "Frequency Multiplier" factor The frequency of lifts and the duration of lifting (in minutes or seconds) over a work shift 19 | P a g e  5. AM, the "Angle Multiplier" factor The twisting angle (A) of the body while lifting, measured in degrees 6. CM, the "Coupling Multiplier" factor The quality of grasp (or coupling, C) classified as good, fair, or poor and depends on the body position (either standing or stooping). If the RWL is below the weight of the object handled, then the task is dangerous and must be redesigned. ❖ Example 1: A worker lifts 10 kg boxes from the conveyor to the cart ten times every minute for two-hours. Answer: 1. Step 1: Determine the weight of the load : 10 Kg 2. Step 2: Assess the six components of the lifting task. 3. Step 3: Select the appropriate multiplier factors for each component of lifting from the tables. 4. Step 4: Determine the Recommended Weight Limit for the task. 23 kg x 1 x.99 x 1 x 0.13 x 0.71 x 1 = 2.1 kg 5. Step 5: Compare weight of the load against determined Weight Limit for the task. The weight of the load at 10 kg is higher than the calculated recommended weight limit of 2.1 kg. 6. Therefore, TASK IS DANGEROUS. 20 | P a g e American National Standards Institute (ANSI) Standard : Management responsibilities Training Employee involvement Surveillance Evaluation and management of MSD cases Job analysis Job design and intervention Force. The amount of effort needed to accomplish a task Repetition. The number of times a given task must be accomplished Awkward postures. When a body part is out of its neutral position Static postures. When a given posture is maintained for an extended amount of time Vibration. When a part of the body comes in contact with a vibrating tool or surface Contact stress. Contact between sensitive body tissues and hard objects Cold temperatures [Environmental]. Exposure to adverse environments such as excessively hot or cold temperatures, air pollutants, noise, and others (Elements of Ergonomics Programs, 1997)  Recommendations: 7. Assess which of components most contribute to the risk. the critical factor is FM for the frequency of lifting and duration of task. 8. Shorten the frequency of lifting by: i. reducing the frequency of incoming boxes in half ii. assigning additional workers to the task iii. shorten the time of the task to 1 hour. 9. Evaluating the Redesigned Task: - Assess the six components of the task in redesigned task. - Determine new Weight Limit. (23 kg x 1 x 0.99 x 1 x 0.75 x 0.7 x 1 = 12.125 kg) - Compare weight of the box against Recommended Weight Limit for redesigned task. The weight of the load at 10 kg is now lower than the weight limit calculated to be 12.125 kg. - Therefore, MOST WORKERS CAN SAFELY PERFORM THE TASK. Lecture 7 Hazards Categories in Workplace (cont’d) VII. Fire Hazards ❖ Introduction. A chemical reaction between oxygen and a combustible material results in heat, smoke, and light It requires Oxygen, Fuel, and ignition source for fire to occur. There are many examples of ignition sources such as Open flames, Smoking, Static electricity, Hot work (welding - cutting), Hot surfaces, Electrical and mechanical sparks, Lightning. ❖ Fire Prevention Plan (FPP) The FPP must be: written, kept in workplace, and available for all the employees. The Employer must: Inform the employees of the fire hazards when assigned to the job review the FPP with every employee. The FPP include: Lists of all major fire hazards, proper handling, and storage of hazardous materials, ignition sources/controls, and fire protection equipment. Procedures to control flammable/combustible wastes Procedures for maintenance of safeguards on heat-producing equipment Name/job titles of employees with responsibilities for maintenance of equipment and control of hazards Tasks require fire protection. Dispensing flammables and combustibles: gasoline, diesel, or natural gas Flammable wastes: solvent waste, oily rags, and flammable liquids Dust Explosions Imperial Sugar Refinery in Port Wentworth, Georgia, a suburb of Savannah. Several lessons can be learned from Case Study 13.1: 1. Dust explosions are a serious hazard. 2. Housekeeping to minimize airborne combustible dusts should be a priority. 3. Corrective actions after a major accident has occurred are essential. 4. Prevention is an important ingredient in an overall fire protection program. 21 | P a g e  Handling of flammable hazards Only use approved metal safety containers or original manufacturer’s containers for storage. Practice good housekeeping. Keep containers closed when not in use. Store away from exits or passageways. Keep away from ignition sources. Equipment: PPEs. (will talk about it in a separated lecture) Fire suppressions. Portable fire extinguishers Fixed systems ❖ Emergency Action Plan (EAP) Benefits Purpose Required elements Written to facilitate actions Describe what should be done Means of reporting. during emergency. during an emergency to guarantee Evacuation procedures Less severe injuries. employees’ safety. emergency escape routes Less structural damage. Show escape routes. Procedures for critical operations Reduce confusion. Tells employees what to do. Accounting of employees Covers expected emergences. Rescue and medical duties Contact persons. Training employees on the EAP General training 1. Review plan with each employee in the following Roles and responsibilities times. Threats, hazards, protective actions When the plan is created Notification, warning, communications When the new employees are assigned Location/use of emergency equipment When any changes are done to the plan or Procedures the responsibilities of any employee. o Emergency response 2. Practice the Plan. o Evacuation and shelter-in-place 3. Educate/train. o Assembly and accounting of employees Types of emergencies o Emergency shutdown. Course of actions Examples of procedures: Functions and elements of EAP Methods of reporting an emergency. Special hazards Instructions for exit. Fire hazards and fire prevention plan Instructions for limited mobility. ❖ Evacuation Workplace evacuation may be required for: 22 | P a g e  Factors affecting response to emergencies: Type/extent of emergency Location of emergency Type of building in which workplace is located. Shutting down critical operations Fire emergencies: Fight or Flee? Options for evacuation Performing a risk assessment 1. Total Evacuation. Is the fire too big? 2. Designated employees authorized to fight fire. Is the air safe to breathe? (All other evacuate) Is the environment too hot or smoky? 3. All employees fight fire Is there a safe evacuation path? 4. Extinguishers provided but not intended for employee use. Evacuation Maps Must show: Actions Taken through Evacuation: 1. Alerting employees Alarm Annunciator panel/speaker 2. Accounting for who has exited (How is that accomplished) 3. Keeping employees informed All clear, re-enter, or remain at assembly point. Clear to leave workplace. Exit Routes: Is Continuous and unobstructed path of exit travel from any place in workplace to (a place of) safety. Should be: Basic Exit route requirements Permanent Separated by fire-resistant materials Limited openings Adequate number of exit routes Discharge leading directly outside or to a place with access to outside Exit door unlocked from inside and side-hinged Adequate capacity 23 | P a g e  Minimum height and width (2-2.3 and 0.711 m) Clearly communicate 2 elements of escape route Exit access pathway Nearest exits from all points of building Pathway away from building structure. No Exit into narrow passages The signs lead to the nearest exit Indicates Exits with for each place wheelchair access No use of elevators to reach an emergency exits. Exits should be more Exits away from than one rooms containing exit. hazardous material Determines where the map is to aid 24 | P a g e worker get to the nearest exit ❖ Extinguishing Systems Methods of fire protection: Fixed extinguishing systems Fire brigades Fire extinguishers ❖ Fire extinguishers Portable fire extinguisher training and education All employees must be able to use fire extinguishers. Hazards of incipient stage fire fighting Operation of equipment (instruction and hands-on practice) Required upon initial employment/assignment and at least annually there after Classes of fires: Class A – ordinary combustibles (paper, wood, cloth) Class B – flammable liquids (gasoline, paint) & gases (propane, butane) Class C – energized electrical equipment (appliances, motors) Class D – combustible metals (potassium, magnesium) Class K – cooking oils and greases (animal fats, vegetable oils) Fire extinguishers do one or more of the following: Remove heat Displace/remove oxygen Stop chemical reaction 25 | P a g e Parts of fire extinguishers Types of Portable Fire extinguishers Large silver container, to 3 ft. tall, 25 lbs. 2/3 water, 1/3 Pressured air Detergents may be added. Cool surface to remove heat Red cylinders, from 5 to 20 lbs. Contains a powder compressed by an unblameable gas Isolates the fuel and interrupt the chemical reaction. Red cylinders, from 5 to 100 lbs or larger, with a hard horn and no pressure gauge. Contains CO2 under extreme pressure, displace oxygen and dry ice has cool effect. Never use in confines space without respiratory protection for kitchen fires Used after turning on built in suppression system Used after turning off electricity as it is filled with conductive chemicals. Potassium bicarbonate may be used in dry types; wet chemical extinguishers spray a fine mist 26 | P a g e How to use the extinguisher? Sound alarm; call fire department Identify safe evacuation path Select appropriate fire extinguisher Discharge extinguisher using P.A.S.S. technique (Pull, Aim, Squeeze, Sweep) Back away once extinguished Evacuate immediately if necessary If Extinguisher empty and fire is not out If Fire progresses beyond incipient stage P.A.S.S. technique Pull the pin Aim at base of fire Squeeze handle Sweep side-to-side at base of fire until fire appears out Watch area for re-ignition and repeat steps 2 – 4; When in doubt, EVACUATE IMMEDIATELY! Elements of inspection: ▪ Inspect bottle, handle, hose, and gauge for proper working order ▪ Inspection tag. Let you know the status of the fire extinguisher. Month and Year put in service current (annual) Monthly visual inspections completed (monthly) Extinguisher product still free flowing inside bottle (turn upside down and/or shake) Lecture 8 Hazards Categories in Workplace (cont’d) VIII. Noise Hazards ❖ What is Noise? Sound that - One does not want to hear. - Varies randomly in intensity and frequency. - interferes with the reception of another sound (masking). ❖ Negative Effects of Noise. - Noise Induced Hearing Loss (NIHL) - Noise can increase blood pressure. - Mental fatigue - Interference with communication can lead to accidents. 27 | P a g e ❖ What is Too Much Noise Exposure? - The risk of hearing loss increases as noise levels increase. - Exposure to noise levels above 115 decibels for even five minutes is very risky. - Impact or banging noise above 140 decibels will cause immediate damage to nerves in the ear. Examples of Noisy Equipment Equipment Noise Level Backhoe 85-95 decibels Chain Saw 110 decibels Front-end Loader 90-95 decibels Gunshot 140 decibels Jackhammer 112 decibels Lawn Mower 90 decibels Tractor 95-105 decibels Circular Saw 90-100 decibels ❖ Audiometric Testing - Check employees’ hearing over time. - Baseline audiogram must be performed within first 6 months of work exposure (8 hour with Time Weighted Average (TWA) ≥ 85 dBA) - Annual audiograms are required each year after baseline audiogram. - Employer must pay for the cost of each required audiogram. - It is done by trained technicians to detect any hearing loss. - Identify occupational hearing loss ❖ Risk Management in workplace noise. Step 1: Identification of Hazard (Noise Sources) ❖ Common Noise Sources ▪ Power press ▪ Air compressor ▪ Waste extraction fan ▪ Ultrasonic welder ▪ Electric motor ▪ CNC machine ▪ Banging and knocking of metal sheets ▪ Milling machine ▪ Grinding machine ▪ Shearing machines 28 | P a g e  Step 2: Assess the Workplace Noise ❖ Noise Standards: ▪ The Permissible Exposure Limit (PEL), 90 dBA for an 8-hour TWA. ▪ The action level (AL), 85 dBA for an 8-hour TWA. ❖ Combining noise from several sources. ❖ TWA and Noise Level Calculation 29 | P a g e  Example Step 3: Select Measures to Control and Reduce Risk ❖ Hierarchy of hazards control Hierarchy is a system in which members of an organization or society are ranked according to relative status or authority. ❖ Control Noise in Workplace ▪ Remove the Hazards. Replace the Noisy machine with less noise machines. ▪ Guard the remaining hazards – Erect isolation enclosure - Machines Enclosure. Structure contains the noise source to protect the workers from noisy machines. ▪ Damping Adding of vibration absorbing material to reduce vibrations which will reduce the noise. ▪ Silencers Devices designed to remove air-borne sound waves that is used in pumps, compressors ▪ Noise Barriers Consist of sheets of wood, plastics, aluminum or steel that reduce noise reaching staff. ▪ Personnel Cabins When the source can’t be isolated, so you isolate who is in danger(the workers) ▪ PPE – Mitigate impact of hazard (E.g. Operator to wear ear plugs or muffs) ▪ Administrative Control a. Job rotation of workers b. Adding periods of quiet hours to the workday. c. Scheduling noisy work when few people is around. d. Notifying people in advance when noisy work is carried out. e. Posting warning signs of noisy areas. We have finally finished all the types of hazards in workplace. 30 | P a g e  Lecture 9 Personal Protective Equipment (PPE) ❖ Introduction As we studied before So, we need to control both hazard and exposure to reduce accident. We Control hazards by engineering the workplace - design tools, equipment, machinery, materials, facilities. We control exposures by managing work and workers. What are PPEs? PPEs are Devices used to protect an employees from injury or illness resulting from contact with chemical, radiological, physical, electrical, mechanical, or other workplace hazards The need for PPE and the type of PPE used is based on hazard present; each situation must be evaluated independently. ❖ Federal OSHA Standard Overview Must be applied to general industry. Governs the use, selection, maintenance, fit and disposal of Personal Protective Equipment Employers must assess hazards in their workplace and select appropriate PPE. Some Caveats PPE is the last resort. The use of PPE signifies that the hazard could not be controlled by other methods, such as: administrative controls (i.e., shift rotation) engineering or industrial hygiene controls Use of PPE means that the hazards still exist in the workplace. Unprotected individuals in the same area will be exposed. Failure of PPE means that the worker will be exposed. PPE can be combined with other controls. ❖ Types of PPEs (what part od the body it Protects) Goggles, Face shields, Eyes Safety glasses Face shield, Protective Face shields, Barriers Head Hard hat, Bump hat Ears Earplugs, Earmuffs Feet Safety shoes, Boots Hands and arms Gloves, Sleeve guards Vests, Safety suits, Safety Protective clothing jackets. Body Shields, Barriers, Restraints Airways / lungs Respiratory devices. 31 | P a g e ❖ Hazard Assessment. Evaluate every job function in every department. Determine if there is any hazards. Check for hazards to eyes, respirator system, head, feet, and hands. Determine which PPE should be used. ❖ The types of Hazard Assessment and selecting the proper PPE. 1. Eyes and Face Assessment Eyes and should be protected from: Flying particles Chemical gases or Vapors Molten metal Potentially injurious Liquid chemicals light radiation Acid or caustic liquids Eye Protection Common uses: Selection Impact Protection Face shields Provides the highest level of protection. Chemical Hazards Safety glasses protect the eye from flying objects. Radiation Protection Chemical goggles Protect the eyes from chemical welder’s goggles fluids by sealing tightly to the face. laser goggles UV Infrared 2. Respiratory Protection Hazard Assessment Assess the workplace if there is: Inhalation of airborne dusts or particulates Inhalation of chemical vapors or fumes Lack of adequate oxygen Identify the specific source(s) of respiratory hazard. Review the work processes to determine the hazard source and magnitude. 3. Head Hazard Assessment Head should be protected from the following hazards: Falling objects Exposed electrical conductors. Low-hanging obstructions Selecting head protection Hard hats protect from impact or penetration. Use electrical insulation hard hats around electricity. Use bump caps around low-hanging objects. Must comply with ANSIZ89 standard. 32 | P a g e  Helmets are classified into: A = General impact, 2200 volts protection B = 20,000 volts protection C = Bump protection, no electrical protection 4. Foot hazard Assessment. Falling, rolling, or sharp objects Electrical hazards Slippery walking surfaces Hazardous chemicals Cold weather conditions Foot and leg protection Protects from: Types of protection provided. Falling or rolling objects Impact protection. Objects piercing the sole compression protection Electrical hazards puncture protection Molten metal Protects from molten metals and welding sparks Hot surfaces Slippery surfaces Safety shoe parts: Steel Toe protects your toes from falling objects. Metatarsal has special guards that run from your ankle to your toes. Reinforced sole has metal reinforcement that protects your foot from punctures. Latex/Rubber resists chemicals and provides extra traction on slippery surfaces. Types of Safety Shoes According to their outsole Beta Ultra grip: Cleated Multi-purpose Outdoor Self-cleaning sole On a variety of surfaces. Superior slip resistance Reduces hydroplaning. and traction Self-cleaning. 33 | P a g e  Safety-Lok Chevron Indoor or outdoor use Indoor and Outdoor In smooth surfaces On hard surfaces Slip resistant. Slip resistant Recommended on wet surfaces 5. Clothing Assessment Hot or cold materials or objects Chemicals Welding hazards Heavy, sharp, or rough materials Moving machinery 6. Ear hazard Assessment Noise induced hearing loss can occur with exposures >90 dBA A hearing conservation program becomes a requirement at exposures >85dBA Higher levels of noise exposure have shorter allowable exposure times Hearing Protection – Types Ear Plugs: Less Expensive Disposable Good ones have high NRRs Difficult to tell if employee wears ones Earmuffs: More Expensive More durable Higher NRRs Obvious Ear plugs and muffs can be used together in very noisy workplace. 7. Arm/hand Protection Should be protected from Chemicals, extreme temperatures, and sharp objects. Injuries include cuts, abrasions, burns, amputations, shock, chemical absorption. Glove protection information Should be obtained from the manufacturer. Protection includes gloves, sleeves, hand pads, wristlets, etc. Rubber insulating equipment needed for electrical workers 34 | P a g e  Types of gloves: Disposable Gloves: One time use Thin and flexible Have improved sensitivity and dexterity. Protect the employee from the material of the material from the employee. Chemical Resistance Gloves: Protects against wide range of chemicals. Totally impermeable Can also be used to protect from cuts absorption and snags. Critical Environment Gloves Used in applications requiring high cleanliness. Found in electronic nuclear and pharmaceutical industries General Purpose Gloves: Intended to help reduce hand injures due to snags, punctures, abrasion, and cuts. Not for chemicals unless other chemical gloves are worn as liners. Temperature Resistant Gloves: Provides protection from extreme temperatures. Lineman’s Gloves: For electricity protection To assure adequate electric protection, properly rated lineman’s gloves should be selected. 35 | P a g e  How To Correctly remove chemically stained gloves 8. Torso Protection Hazards include heat, splashes from liquids, impacts, cuts, and radiation Injuries include heat burns, radiation burns, and chemical burns, lacerations, and abrasions. Equipment includes vests, jackets, aprons coveralls, and full body suits 9. Respiratory Protection Protects users by removing harmful materials that may enter the body via the lungs Inhalation is one of the quickest, most efficient ways to introduce lethal levels of hazardous materials into the body. Types of Respirators: Air Purifying Respirators (APR) : Half-face Full Face Powered Air Purifying Respirators (PAPR) Self-Contained Breathing Apparatus (SCBA) 36 | P a g e  Air-Purifying Protection Protects workers from gases that may be harmful. Propper filters and cartridges should be used. This type of respirator should be used only if: o The concentration of the harmful gas is not exceeded for the mask. o oxygen is present in amounts greater than 19.5% o The atmosphere is NOT Immediately Dangerous to Life or Health Mechanical Filter Elements: Provide protection by physically trapping it in the fibrous filter material. The filter contains an electrostatic charge the attracts particles toward it. As its effectiveness it should be changed when breathing gets hard. Chemical Cartridge Elements Filled with specially treated active carbon. Should be changed when any taste is detected or with scheduled. 10. Fall Protection Consists of: Anchorage Connector Shock Absorbing Lanyard (Connectors) Full Body Harness The anchorage must be attached to a suitable and strong attachment point. 37 | P a g e  11. Selecting General Work Clothing Long-sleeve shirts and long pants Flame-retardant clothing No loose clothing or jewelry Chemical-resistant clothing Safety Signs and Tags the warning industrial workers The word sign refers to a surface prepared for of safety instructions members of the public who may be exposed to hazards. News releases, displays commonly known as safety posters, and bulletins used for employee education are not safety signs. Specifications for accident prevention signs and tags. o OSHA 1910.145 and ANSI Z535.2 applies to all signs related. o These specifications are intended to cover all safety signs except those designed for streets, highways, railroads, and marine regulations. o These specifications do not apply to plant bulletin boards or to safety posters. OSHA 1910.145 classifies signs according to use into three categories: Danger signs Caution signs. Safety instruction signs. o Warn of specific Dangers. o Warn of Potential o Used for general o Radiation hazard. hazards. instructions. o Must all have the same o Warn of unsafe practices. o Used for suggestions type of design. relative to safety o Used only with immediate measures. danger. 38 | P a g e  Accident Prevention signs are classified by ANSI Z535.2-2002 into eight classes: 1. Danger: immediate hazard that if not avoided will lead to great injury or maybe death, it is limited to the most extreme situations. 2. Warning: Potential hazard that if not avoided can lead to great injury or maybe death. 3. Caution: Potential hazard that if not avoided may lead to minor or moderate injury - Also, can be used to alert of unsafe practices All the previous three classes of signs should not be used for the present of property damage risk, they can be only used for the personal injury risk. 4. Notice: Indicates a statement of the safety policy of the company. - Should not be used in a hazardous situation. 5. General Safety: Indicate general instructions relative to safe work practices, reminders of proper safety procedures, and the location of safety equipment. 6. Fire Safety: Indicate the location of emergency firefighting equipment. 7. Directional Arrow Signs: used to indicate the direction to emergency equipment, safety equipment, and other locations important to safety. 8. Special Signs: Now we will discuss the design of each category of signs on its own. 1. Design of Danger Signs. There Should not be variation in the designs of danger signs. Employees should be instructed that danger signs means a high risk of major injury or death The colors red, black, and white shall be those of opaque glossy samples. 2. Design of Warning sign The word “WARNING” in black letters on a rectangular orange at the top of the sign. The safety alert symbol should be before the “WARNING” word. The base of symbol should align the base of the letters and the height is equal or more than the height of the word. The message panel should be in black letters on a white background or white letters on black background. 39 | P a g e  3. Design of Caution signs The “CAUTION” is in yellow letters with black background. Any other word shall be black in a yellow background. 4. Design of Notice signs Notice headers provide information of a general type to avoid confusion. The message shall be in blue or black letters on a white background. The symbol/pictorial panel, if used, shall be square with a safety blue or black symbol on a white background.. 5. Design of General Safety signs “SAFETY FIRST,” “BE CAREFUL,” “THINK,” “SAFETY INSTRUCTIONS,” etc. The signal word in white letters and green rectangle at the top of the sign. The message in black, and white background 6. Design of Fire Safety signs do NOT have a signal word. The message shall be red on a white background. Symbol/Pictorial Panel -if used- shall be red on white or white on red. 40 | P a g e  7. Design of Directional Arrow Signs The arrow should be white on black or colored background. The arrow should be in the uppermost part of the sign. 8. Special Signs Slow-moving vehicle emblem. o Consists of a fluorescent yellow-orange triangle with a dark red reflective border. o Yellow-orange fluorescent triangle is visible in day-light and the red border creates a red lighting triangle at night out of reflecting the front light of other vehicles. o Used in the vehicles moving slowly by design (25 mph or less) in roads. Piping systems shall be identified: o Pipes, fittings, valves, and pipe coverings RF Radiation hazard warning Laser (Caution/Warning – According to ANSI Z535.2-2002) Ionizing radiation warning signs, labels, and signals shall contain the radiation symbol. 41 | P a g e  Material Safety sigs: o The National Fire Protection Association (NFPA) Developed a hazard identification system for emergency responders. o The NFPA diamond provide a visual representation of the hazard type. o Meanings of the data displayed in each color: 42 | P a g e  ❖ OSHA 1910.145 Accident Prevention Tags What is tags? o Tags are used in hazardous conditions to warn the employees. o Made of paper, plastic, card, or other material. o Rectangular, not smaller than 3 in x 5 in (7.6 cm x 12.7 cm). o Corners may be square cut, chamfered, or rounded. When to use tags? Prevent illness or injury of employees who are exposed to hazards or potentially hazardous conditions. Equipment or operations that are not ordinary, not expected, not readily apparent. Should be used till the hazard is eliminated. Tags are not needed when signs or guarding are used (Just one thing to warn of hazard) General Design of tags The signal word. Major Message Categories of tags and their uses: Category Use Color immediate hazard presents a threat of death or serious Red with letters in Danger Tags contrasting color injury to employees. Minor hazard, presents a lesser threat of Yellow with letters in Caution Tags contrasting color employee injury. Orange with letters in Warning Tags Hazard level between caution and danger contrasting color Background: yellow Panel: reddish-purple Radiation Anything that contains or is contaminated with Letters: Black hazard tags hazardous radiation hazards. The radiation symbol must be displayed. The radiation symbol Biological identify the actual or potential presence of a biological must be displayed. Hazard tags hazard The Biological symbol must be displayed. 43 | P a g e  Other Tags: Other tags can be used if the condition does not meet any of the previous descriptions. Control of hazardous energy sources Lockout/tagout standards, methods, and devices ❖ Hazardous Energy. ▪ Is any type of energy that is enough to cause injury to a worker. ▪ Common sources: Electricity, Mechanical Motion, pressured air, and extreme temperatures ▪ May occur in the installation or repair of any of any machine or equipment. Employer Responsibility ▪ Shall establish an energy control consisting of: energy control procedures employee training periodic inspections. The program should ensure that before any operation are made on any machine or equipment that contains hazardous energy, the machine MUST be isolated from any power source. ❖ Lockout/Tagout ▪ refers to specific practices and procedures to safeguard employees from the unexpected energization or startup of machinery and equipment, or the release of hazardous energy during service or maintenance activities. 1. Lockout: Is the process of isolating an equipment from a power source until lock is removed. The lock out device is any device like lock, block, or chain that keeps a switch in OFF. 2. Tagout: Used to indicate that there is a process in going on a specific equipment or machine so it is disconnected from electricity (Isolated) and it will not be operating till the tagout is removed. Tagout device must clearly state the tagout message. Valve lockout/tagout. Electrical lockout/tagout. Contains of Lockout/tagout center. Keyed padlocks (two each of blue, gold, green and red) Valve cover Plug locks, one small plug lock. Lockout checklist forms Hasps "Do Not Start" tags "Danger" magnetic signs, Cable ties Copy of OSHA Standard 1910.147. 1910.147. 44 | P a g e ❖ Hazardous Materials Transportation. Department of Transportation (DOT) requirement. ▪ Knowing the general regulations and Job specific requirements ▪ Identify hazardous Materials, and how to prevent it. OSHA 49 CFR 172.101 created naming system to identify the hazardous materials: DOT and the United Nations (UN) divide the hazardous materials into 9 classes: Note: the class number in the bottom of the lapel Class 1: explosive Subdivided into 6 sections. Explosives include: 1.1 - Mass explosion hazard sporting ammunition 1.2 - Projectile hazard blasting charges and detonators 1.3 - Fire, minor blast or projectile fireworks 1.4 - Minor explosion 1.5 - Very insensitive explosives 1.6 - Extremely insensitive Class 2: gasses (compressed, liquefied, or dissolved under pressure) Hazard due to the high pressure contained. Three Subdivisions: 1.1 - Flammable gases (Red) 2.2 - Non-Flammable, Non-Poisonous (green) 2.3 - Poisonous Gases (white) Class 3: flammable liquids Flammable liquids can be ignited in room temperature. Combustible Liquids require some degree of pre-heating to ignite. Number 1 rule - eliminate ignition sources. Class 4: flammable solids or substances 4.1 - Flammable Solids 4.2 - Spontaneously Combustibl e 4.3 - Dangerous when wet. Class 5: oxidizers With strong fuels, oxidizers can create conditions which can lead to violent combustion. Many Organic Peroxides are very unstable. 45 | P a g e  Class 6: poisonous or infectious substances. Poisonous: Can include severely irritating substances. “Tear Gas”, Hydrocyanic acid, Carbon Tetrachloride. Infectious substances: that can cause diseases to human like blood or any body fluids. Class 7: radioactive substances Shipped in specialized containers. Exposure does not always result in contamination. Safety Rules: Time, Distance and Shielding Class 8: corrosives Materials which cause destruction to human skin tissue or a liquid that has a severe corrosion effect on meals. – reacts with steel and aluminum. Class 9: miscellaneous dangerous substances Not any of the previous categories ORM A - Dry Ice ORM B - Quick Lime, Metallic mercury ORM C - Asphalt, Battery parts ORM D - Consumer commodities ORM E - Hazardous substances and hazardous wastes You are the first responsible of your safety. 46 | P a g e