Chapter 7. Reta Safety

fire classification, fires are classified into class A, B, C, and D fires.

Class A fires are burning wood, paper, Rags, rubber, many Plastics, or similar fuels.

Class B fires are burning oil, gas, grease, or other flammable liquids.

Class C Fires are fires in electrical equipment. The actual fire is usually burning insulation or insulating oil, but electrical current is likely to be present.

never stand directly in front of, behind or even under an ammonia valve when opening or closing it. The valve packing May sometimes stick to the valve stem and tear enough to allow some leakage. The jet of ammonia that can Xscape along the stem is highly concentrated. Such an ammonia jet has burned faces, permanently damaged eyes, and made people unconscious. It is always best to wear your PPE whatever opening and closing valves. In most cases, is appropriate to loosen the packing nut so the packing is free to move. Note that when loosening a packing nut caution must be used. Always check with your company PPE policy when working with ammonia.

Values with screw type bonnets have been known to unscrew while the operator was in process of opening this type of valve. Always be aware the type of valve Bonnet when opening or closing a valve.

never use pliers when a wrench is needed. Keep hand tools clean before putting them away. Keep all power tools and proper working order. Make sure all guards are in proper working order before using.

a voltage difference between two points of contact is necessary to create a shock. This voltage difference can be caused by touching two wires with a voltage difference between them, or by touching one wire, which is hot, to ground.

before any steam cleaning is done, have the evaporator pump down all refrigerant pump down and pumped out. In some plants, a bypass around a pressure regulator valve can be open to Aid this pump out. If this is not possible, the suction valve should remain open while steam cleaning to relieve any pressure build-up. Contact the refrigeration designer of your plant for the proper cleaning method and review these methods after any modification of your refrigerant plant. It is always good practice to review these plans with a what F attitude. In addition, follow your company's lockout tagout policy.

horseplay any mature workers should realize horseplay belongs on the playground and not in the industrial plant. Yet every year, there are many accidents caused by Childish, thoughtless actions. For example an individual sticks out his foot to trip a passing worker. The worker Falls and Strikes his head on a bench. Several stitches and hospitalization are necessary.

foam type extinguishers are excellent on Class B oil fires, and can be used on Class A fires, but cannot be used on Class C Fires. The highly effective action of the stems from its ability to make water float on flammable liquids and fuels that are lighter than water. And extinguisher is discarded, and a film forms and floats over the fuel surface producing a vapor seal that extinguishes Class B fires.

CO2 fire extinguisher a carbon dioxide extinguisher is he heavy steel tank of liquid carbon dioxide. The pressure in the tank will be from 700 to 1000 PSIG depending on the temperature when the valve is opened by squeezing the handle liquid carbon dioxide vaporizes and comes out of the horn shaped nozzle. Carbon dioxide gas is so heavy that it will form a blanket to displace air and smother the fire CO2 can be used on Class B and Class C types of fires it will smother an oil or electric fire.

to emphasize chemical safety, the occupational safety and health administration OSHA has issued a hazard communication standard that helps us maintain a safe and healthy workplace.

MSDS sheets MSDS sheets gives detailed safety information about the chemicals in the product that we are using so that we can protect our health while using this product the MSDS identify the manufacturer and emergency telephone. The substances hazards ingredients, chemical ID, common names, and recommend limits or also included. The physical and chemical characteristics, such as boiling point vapor pressure, Vapor density, and evaporation rate Etc. Are included as well as physical hazards such as Hazard and explosion limits and the appropriate type of fire fighting equipment and procedures. Reactivity data help the user determine how to store the chemical by indicating if the chemical will decompose dangerously or it is a hazardous with other substances.

if the correction takes more time or material than he can easily devote to it, he should notify his supervisor immediately of the situation. In an accident occurs, there should be an investigation. The purpose of this investigation is not to lay blame on anyone, but rather to find the reason why the accident occurred and to find a remedy. If the accident is caused by personal error, mistake should be publicized so all can avoid them in the future and possibly prevent the same type of accident from happening again.

Safety Committee, the Safety Committee should be responsible for the safety program only. it would be the safety committees responsibility to point out to management unsafe conditions and make recommendations about physical changes necessary to eliminate hazards.

guidelines for the Safety Committee common the Safety Committee should meet on a regular schedule, normal business should not be allowed to interfere with or delay the safety committee meeting. And eat safety committee meeting there should be written minutes of the previous meeting and these meeting should be read at the beginning of each meeting. This will act as a review of the last meeting and establish a record of past meetings.

after each accident, an investigation of the accident by a Safety Committee should take place, with the intention of finding the cause of the accident, so that a proper solution can be found to prevent the same type of accident from happening again.

ammonia is considered a toxic substance, however it is not a cumulative chemical to the human body in the human body produces 17000 mg of ammonia per day. Ammonia is lighter than air and has a sharp, pungent odor that serves as a warning when present. Pure ammonia is hard to ignite, and has limited explosion potential. However if oil is mixed with ammonia Vapor you have a completely different condition. This condition is based on the amount of oil that is Airborne. Again, pure ammonia is not considered a flammable gas. Department of Transportation classifies it as a non flammable gas. In an enclosed area, however in concentrations of with an ignition temperature of approximately 1600 degrees Fahrenheit or higher, it is combustible. If oil vapor is present these limits are considerably lower. For this reason, all engine room should be well vented.

ammonia in the air can be detected by smell when there are only five parts per million present. 100 times this amount gets very irritating to the nasal passages, lungs,and eyes. if inhaled and much higher concentrations it will burn the lungs. note that it's odor in irritating properties are excellent warning agents. If a person is physically able to move, he will leave the area. When ammonia is smelled or detected,the leak should immediately be found and corrected.

fire hazards, most refrigeration and maintenance employees will go through a lifetime without encountering a fire at work. But, in case you are one of the few who will be in a plant when a fire starts, the following points should be understood.

any fires require three things to start or keep it burning. It must have fuel, air to supply oxygen, and they kindly temperature. If one of these elements is removed, a fire cannot start, or, if already started it will go out.

proper lifting no matter how knowledgeable or skilled we are, we all need to be reminded about ways to avoid back injuries. Lifting is a skill that needs to be learned properly and practice regularly. If you have to lift a load up to a point above your shoulders, you should plan ahead so you can rest the load about waist height, then change your grip and finished the lift. You should always size up a job before you start lifting. If it is too big or awkward, don't be afraid to ask for help. It's not just the weight that makes a load a two-person job, it's also the item size and shape.

chemical safety, chemicals are part of our Lives. Modern Life would be impossible without chemicals. Plastics, drugs, and Miracle fibers are just a few of the things that use chemicals in their manufacture. Benefits of chemistry and chemical base products are unquestionable. However all chemicals have to be treated with respect. Many can cause injury or illness if not handled properly.

hazards of ice handling, handling large ice blocks can create special hazards that are not found in cold storage or food processing plants. the floors of ice storage rooms are likely to be Frosty or icy and slippery. Be careful and walking to avoid slipping and falling. Boots are shoes with non-skid soles are available and recommended.

common ice blocks weigh 300 pounds each, or slightly more to allow for some meltage and still leave 300 lb. Very few plants make 400 lb blocks. If these blocks of ice tip over and strike a person common injuries will result usually a broken leg or Crush foot.

ladders maintenance off of requires overhead work that must be reached by portable ladders. Only ladders in good repair should be used. A crack in a wooden ladder is likely to open when loading and cause a failure. Ladder should not be painted. Paint can hide cracks, oil or varnish can be used if a finish is desired. Be sure the ladder is solely and squarely placed before climbing it never place a straight single letter at an appropriate angle. The distance between the foot of a straight ladder and the base of the structure should be about 1/4 of the distance from the base to the point of bearing. Never use a step ladder as a straight ladder by leaning against the wall.

do not use to short a ladder so that it fails to extend at least 3 ft above the point of the bearing. Do not try to reach too far in any direction while on a ladder do not stand or climb to the top of the three rungs of the ladder. If working on or around electrical equipment or wires while on a ladder, a nonmetal metal used. Do not use a wet wooden ladder, a wet wooden ladder will conduct electricity. Be extra careful of tools while on a ladder. Do not leave tools hanging from the ladder rungs, or leave tools on top of the step ladder shelf. Never throw tools to a person on a ladder. A drop tool may hit someone or may drop into moving machinery.

liquefied gas extinguisher, in a liquefied gas exchange your, liquid vaporizes into a heavy Vapor that displaces the air and Smothers the fire. The vapor from these extinguishers is toxic, and must not be used in a confined space or an unventilated room. For this reason, vaporize liquid extinguishers have been outlawed in many areas. However it is possible that a few old ones are still around, please check with your local fire department before putting them into service.

dry powder extinguisher for metal fires. A dry powder extinguisher for metal fire should not be confused with a dry chemical extinguisher. Dry chemical extinguishers must not be used on Class D fires. The need for a Class D fire extinguisher in a refrigerated facility is very remote and is intended for a special Hazard protection only.

methyl chloride is a toxic and flammable halocarbon refrigerant. It is now Obsolete and not used in any new equipment it is possible to encounter it, however in pre-World War II plants. It's toxic properties and particularly dangerous because they are not irritating. It will not drive a worker out to open air. Methyl chloride smells like ether and has the same effect as either. That is it is a fixie a Ting and has even caused deaths.

electrical hazards, most Refrigeration compressors are driven by electric motors. Sparks or smoke from a motor or other electrical equipment can mean a shock or a fire hazard. Turn off the power and report this condition. Odd jobs around the plant require the use of electrical power tools or hand tools. We must know how to work safely with these types of electrical equipment and tools. Excessive pressure or Force should not be used on any hand tool. Saw should be kept free of rust so they are less likely to bind or junk. Never use any tool other than a hammer for a hammer, also check Hammer handles to make sure they are firmly attached. Never hold work in your hand or lap while using a screwdriver. The tool Under Pressure could slip and pierce your hand or leg.

conveyors in the floor are often used to drag ice blocks into the ice storage room. Watch your step when walking over them, never work on a conveyor, stopped or moving. ice storing machines and ice cubes are frames with power-driven saws. ice scores saws Cruise in the large blocks to Aid and breaking them into 25 and 50 lb blocks. I skewers saw large ice blocks into cubes which are those that are used in restaurants as gourmet ice cubes. Use the conveyors drag the large ice blocks into the score or cuber.

frostbite frostbite is usually freezing of a body part, which occurs when the body is unable to supply enough heat to counter react severe cold. Voiding exposure to severe cold conditions is the best possible way to avoid frostbite. Dress properly and avoid alcohol and come out of the freezer when you begin to feel cold. Dressing properly means dressing in layers and avoiding tight fitting clothes. The head and neck lose body heat more rapidly than any other parts of the body.

hearing protection, hearing lost because of noise can creep up on you with no symptoms or Warnings of any kind. It's progress is so slow that it is not noticeable until it is too late. Working in a high noise area without hearing protection will increase hearing loss. Don't take your hearing for granted. Even for 5 minutes. It's important that you allow all the safety rules and instructions wherever they are posted.

hazards, ammonia hazards, ammonia has been used in ever-increasing quantities since the 1870s when mechanical Refrigeration was introduced. Depending on the age and design of the refrigeration plant, as much as 60000 lb of ammonia are often used. The refrigerant charge could also be greater in plants with blast freezing capabilities. The point is that millions of tons of ammonia are presently used in refrigeration plants throughout the world.

first aid for ammonia, anhydrous ammonia can be hazardous to the human body and both liquid or vapor form. The first step to be taken for first aid is to remove the person who is to be treated to a safe area. When someone is splashed with ammonia injury usually starts at once, so first aid should be immediate. If the eyes are Splash with liquid ammonia or exposed to a heavy concentration of vapor, they should be flush with water for at least 15 minutes before the injured person is sent to the doctor or while waiting for emergency help.

if liquid ammonia contacts the skin, it can cause severe burns. The skin should be flushed thoroughly with large quantities of water for at least 15 minutes while removing any clothes that may have been splashed with ammonia. Caution clothing may freeze to the skin if Splash with liquid refrigerant. Remove the clothing while washing Down Under the emergency shower.

industrial batteries all refrigerators the cilities have some type of material handling equipment that is operated by industrial batteries. Proper care and handling these batteries must be taken or a serious accident can happen. Always use proper lifting equipment when changing a battery. Always shut the charger off first before disconnecting the battery from the charger, and keep all battery vent caps in place and secure while charging batteries.

in addition, covers on batteries or truck should be open during charging to prevent accumulation of hydrogen gases. Gas is produced by the battery during charging or explosive, so do not smoke, use an open flame, or creates sparks near a charging battery, keep all battery rooms well ventilated.

all big fire started small fires. A small fire is easy to put out with a small portable fire extinguisher. Large fires can only be put out by large fire fighting equipment such as provided by City Fire Department. If a fire starts, it is best if someone calls a city fire department at the same time the fire is attacked with a portable fire extinguisher. Most portable fire extinguishers will empty themselves in less than a minute. If the smallest extinguisher is not enough to stop the fire, the sooner the fire department arrives, the better come firefighters will not object to finding a fire already put out. It is also important to invite your local fire department representative into your plant for a tour, so that you can develop an emergency action plan together in case a fire occurs.

in case of fire starts take the following steps. One Sound the Alarm immediately. To warn all people in the area immediately. Three have someone meet the fire department. For if trained to do so, try to extinguish the fire with proper handheld equipment.

where to go for help, fire extinguisher manufacturers, your insurance company, local fire departments, and most importantly, the national Safety Council has films and posters explaining the maintenance and operation of portable fire extinguishers. National Fire protect Association publication NFPA 10, portable fire extinguishers, has important information that deals with training employees and using portable fire extinguishers. For inspection, testing, and maintenance of a sprinkler system, NFPA bulletin 13A is very helpful.

lifting items, improper lifting, and proper lifting is the cause of many back injuries. A person with an injured back is likely to have back trouble for the rest of his life.

draining oil draining oil is a fairly routine tasks that is required in most of our refrigeration systems, and, if not perform correctly May create a hazardous condition. Although it may appear to be a simple task and it sometimes are formed every day, it should not be taken lightly. Before draining from refrigeration systems, we must ensure the following

number one let your supervisor know where you are at the tasks that you are about to do. Number to know and follow your company standard operation procedures sop for draining oil. Number 3 have your required PPE on period number for be familiar with your company emergency action plan.

dry chemical extinguisher dry chemical extinguisher is a tank that contains a powdered type agent and has either a pressurized cartridge for the propellant, or stored pressure in which the entire container is pressurized. When the handle is pressed the pressurized cartridge is punctured, and gas pressure forces the powder out of the hose. The extinguisher can be used intermediately or continuously. There are four types of bass agents for dry chemical fire extinguishers, these are sodium bicarbonate, potassium bicarbonate, potassium chloride, and ammonium phosphate. not all dry chemical extinguishers can be used on any fire. Ammonia phosphate base dry chemical is used on multi-purpose fire extinguishers, but is less expensive than water or on a Class A fire and will not reach deep-seated fires. Is important that all burning material is Thoroughly covered by the chemical agent.

powder form a dry chemical extinguisher is not poisonous. However it will irritate the lungs if much of it is inhaled. It is like an any other dust in this respect. Check the label on your dry chemical fire extinguisher for the proper location and use.

inhalation of a large amount of ammonia vapor is a serious matter and should be considered lightly. Different degrees of first aid will be required because of the nature of the accident. Regardless, medical attention should be sought immediately. And, most important, first aid should only be given by a qualified person

proper housekeeping Good Housekeeping will help prevent fires and promote a safe working environment. Combustible material should be stored in approved containers. Oily rags and such should be disposed of properly and not allowed to accumulate or sit overnight. Keep all fire exits free and workable. Observe all non-smoking signs and rules. Proper housekeeping is just one step to help prevent fires.

the Safety Committee should be comprised of all department heads and an employee from each department. For example, the plant superintendent, office manager, chief engineer, forklift driver, production people, maintenance man, Etc, should be members of the committee.

protection equipment, clothing and personal protective equipment, safety begins with safe clothing and proper personal protective equipment, PPE.

do not wear any metallic objects while working on a battery and never lay any metal tools on top of battery. You should always wear your PPE, such as a face shield, rubber apron, gloves Etc.

slugging of compressors, liquid slugging and Refrigeration Vapor compressors can cause serious equipment damage. Equipment broken by liquid slugging as cause fatalities.

hazards with synthetic refrigerants, modern synthetic refrigerants in most cases are non-toxic and inflammable. However, they can be hazardous. A bad leak in a closed room or even a tank that is open only at the top can displace all the air. Any person in such an atmosphere will be smothered because of lack of oxygen. These refrigerants are heavier than air, so a meat will fill a tank top from the bottom. Water is not a poison, but if a person is submerged in it, he will not live long. It is the same with all heavier-than-air chemical Vapors.

some synthetic refrigerant made break down to irritating and highly toxic compounds when in contact with an open flame or heat. Soldering or welding in the presence of a synthetic refrigerant may be hazardous and should be avoided until the area is vented properly. Oxygen detectors should be used in all refrigerant machine rooms where the refrigerant cannot be detected by odor.

ice blocks are handled with ice tongs. The first line of defense against an accident with Tongs is to keep them sharp. They should bite into the ice security and deeply so they cannot slip. Don't grab an ice block with tongs too near the edge of the block. The sharp tongs can slip off the edge of the block, leaving a person pulling on nothing but Air instead of 300 lb of ice.

sometimes ice blocks are brittle enough to crack when exposed to the air. Watch for cracks and ice blocks. Handle a cracked block with extreme care, these heavy blocks of ice may fall apart when pulled or jerked, which will leave a sharp Jagged Edge from which a person could receive a serious injury.

never tie short ladders sections together to make a long ladder, or stand ladders on boxes or other objects to gain additional height. When adjusting the length of an extension ladder, make sure the Locking device is fully secured before using the latter. Never tried climbing a ladder with one hand, and carry something in the other hand. Instead voice them from the ground to the job in a strong bag or bucket and always follow the manufacturer's recommendations.

steam cleaning evaporators, food processing equipment such as evaporators make steam cleaning and sterilization after use. This is usually done by production people rather than Refrigeration technicians. Nevertheless the refrigeration mechanics must be aware of what procedures are used while cleaning. If necessary, we must see the proper valves remain open. Does that stirs explosions have occurred when a steam hose has been turned on to an evaporator containing liquid refrigerant. The high temperature steam can cause the liquid refrigerant to expand, building up a pressure far beyond design working pressure of the equipment.

every plant should have a schedule disaster drill at least two times a year. Be prepared for any type of disaster that may occur could save lives and property damage. It is also recommended that a written disaster plan be prepared and reviewed once a year by the Safety Committee and updated when there is a change in the facility or Personnel duties.

suggested agenda for safety committee meetings, read minutes of last meeting, report on Plant tour by Safety Committee, review accidents recommendations, report old Business, Report new business.

hazards in a refrigeration plant

the refrigeration engineer and maintenance technician should be aware of conditions in the plant that might cause an accident, Hazard. If he finds an unsafe condition that can be easily corrected he should have neatly correct it himself and Report the correction to the receivable supervisor.

color coding and identification of piping systems. Unmarked pipes and valves can mean danger to both life and property. Numerous injuries to personnel and damage to property have occurred because of mistakes made in turning valves on and off, or opening the wrong pipe at the wrong time or place, particularly when outside agencies, such as municipal fire departments, we're called in under emergency conditions. New or transferring employees can also be confused by Mazes of unmarked pipes. Color coding and identification of pipes makes our plants safer to operate by taking the guesswork out of the pipe tracing. A proper identification system instantly tells all you need to know about the contents of the pipe, whether hazardous or safe, and the direction of flow

to make the job of pipe identification easier, companies such as w. Bradley Company and Seton name plate Corporation make pipe markings that comply with the ANSI a 13.1.

the responsibility of the maintenance and inspection of a fire extinguisher should be given to one person. All fire extinguisher should be inspected on a monthly basis with a tag fastened to each fire extinguisher showing inspection dates and by whom the inspection was made. The purpose of this inspection is to make sure that all fire extinguishers are in their design Place, have not been tampered with or actuated, and are in proper working order. All fire extinguishers should be inspected yearly by a fire extinguisher service company and hydrostatically tested every 5 years.

unacceptable and obsolete fire extinguishers, only extinguishers listed by the national recognized agencies, Underwriters Laboratories, Incorporated. Factory Mutual engineering Corp. Or your insurance company should be used. All other fire extinguishers are unacceptable.

with or without such markings, read the label on all extinguishers in your plant. If a fire starts, there is no time to stop and read extractions. The label should give the type of extinguisher, the type of the fire it can be used on, and any operating instructions necessary. If a portable fire extinguisher does not have any such markings, the extinguisher should be discarded.

water type solution extinguisher, water type solution and fire extinguishers are effective only on a Class A fires. A 2.5 gallon size is common. This type of extinguisher has a pressure gauge on it to show if pressure has been lost. When the needle is on the green area of the gauge, pressure is satisfactory. If the pressure is low the tank should be refilled to the proper pressure, by a qualified person. Most stored pressure fire extinguishers are operated by removing a locking pin and squeezing the handle. It is important on all water type extinguishers to inspect a nozzle regularly for foreign particles that may cause the extinguisher to fail. Extinguishers exposed to freezing temperatures must be protected from the freezing.

eye protection, any worker who gives without eye protection on a job when it's needed is risking Serious injury to his eyes and possible loss of his livelihood. It takes less than a minute to put on some type of eye protection, it takes only a fraction of a second to regret, for the rest of your life, that you did not take that minute. In addition, contact lenses are not designed to protect the eyes. If a caustic solution is splashed in the eye, a contact lens can further complicate the injury.

wearing protective life rejection is no different than looking both ways before crossing a street or putting on a seatbelt.

another electrical Hazard is danger of burns from the heat generated in a direct short. If a screwdriver other metal object is dropped across the bar electric line or terminal, the short created melts and splatters some of the metal, both from the tool and point of contact. This molten metal will cause severe burns. Naturally, the tools or terminals will also be hot enough to burn. Loose connections carrying a large current will have enough resistance to generate heat. If these loose connections are touched, a burn results.

when you work on a piece of electrical equipment, you must follow your company lockout tagout program for hazardous

class D fires are fires that occur in combustible Metals, such as magnesium, titanium, zip chromium, lithium, potassium, and sodium, and are not likely to be in a refrigerated facility. these are specialized techniques, extinguishing agents, and equipment to control and extinguish class D fires. Normal extinguishing agent should not be used on metal fires because of the danger of increasing the intensity of the fire.

you should know the types of fire extinguishers that are in your plant, the best one to use on each type of the fire, and, especially, when certain extinguisher should not be used. Portable fire extinguishers have markings to show on which type of fire they may be used. Extinct Ritter's suitable for class A should be identified by a triangle containing the letter A. If the colored, the color should be green period Class B extinguisher should be identified by a square containing the letter B, if colored the color should be read. Class B extinguisher should be identified by a circle containing the letter c. If colored, the color should be blue. This marking system may not be found on older extinguishers.

because 120 volts is so common, some individuals get careless with it. 120 volt kills more people than all higher voltage accidents put together. So, remember, if you are sweaty or dry, 120 volt shocks can be fatal.

you should not work near expose high voltage lines or switches and less trained to do so. High voltage not only shocks, it also punctures and burns the skin at the point of contact. Air is a poor insulator and high voltage will jump through it to a person who is grounded. The general rule is to accept electricity to jump about one inch for each thousand volts.