SAFETY Page 1 SAFETY PRACTICE IN GENERAL CHEMISTRY

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1 SAFETY Page 1 SAFETY PRACTICE IN GENERAL CHEMISTRY The chemistry laboratory can be a safe place to work provided that safety precautions are thoroughly understood and followed. This involves an awareness of the potential hazards and the correct procedures to minimize these threats. Three general areas of safe laboratory practice are preventive measures before the experiment, preventive measures during experimentation, and proper response if an accident occurs. Close adherence to the policies and procedures outlined below will insure a safer and more pleasant laboratory environment. Preventative Measures Before the Experiment The overriding principle in laboratory work is that of using common sense, both when planning and doing experimental work. The following common-sense measures must always be followed in the laboratory. 1. Eye protection must be worn by EVERYONE in the laboratory AT ALL TIMES!! Proper eye protection means either splash proof glasses or goggles. Splash guards may be attached to prescription glasses (but not sun glasses), or goggles may be worn over them. Contact lenses pose a special hazard, since there is the possibility that a corrosive material might flow under a contact lens and cause permanent damage to the eye. Also, some soft lenses will absorb chemical vapors and release them in the eye for hours. Therefore, splash-proof goggles or glasses should be worn over contact lenses in the laboratory. 2. There must be no eating, drinking, or use of tobacco in the laboratory. This could result in the accidental ingestion of toxic substances. 3. Appropriate clothing should be worn in the laboratory. Baggy clothing, especially when it has large floppy sleeves, may become entangled in equipment or chemicals on the lab bench and contribute to an accident. You may want to wear old clothes or else wear a lab coat to protect your clothing. 4. Bookpacks, purses, coats, sweaters, etc. should not be placed on the floor, as they interfere with safe movement around the laboratory, nor should they be placed on the laboratory bench as they may interfere with conducting the experiment (not to mention running the risk of being damaged or destroyed by contact with acids or other corrosive substances). A rack is provided in the laboratory on which you may hang these items. 5. Everyone with long hair should tie it back to prevent it from hanging down into a Bunsen burner flame or dangling into various chemicals, or even becoming entangled in certain laboratory apparatus. 6. You must wear shoes in the laboratory. Sandals, thongs or flip-flops are not acceptable. Such footwear provides little, if any, protection from spilled chemicals or broken glass. 7. Unauthorized experiments will not be tolerated! You must have supervision for all experimental work. Never work alone in the laboratory! 8. Common sense dictates that the laboratory be a work place not a playground. There is no room for horseplay. Such behavior will result in immediate removal from the lab. 9. And finally, the most obvious preventative measure that can be taken is to thoroughly acquaint yourself with the experiment that will be performed. Take special notice of any cautionary statements about procedures to be employed in the experiment. Do not place yourself in the position of having to read step-by-step the procedure for the first time when you enter the lab. There is no excuse for not being familiar with what you will do after you enter the lab, and in this way you will not be surprised by an easily preventable accident.

2 Page 2 SAFETY Preventative Measures During Experimentation During the performance of an experiment there are some general procedures that help prevent many accidents: 1. Chemicals should never be tasted and should only be smelled with appropriate precaution. Rather than taking a deep whiff of a potentially malodorous (or toxic) substance, a gentle wafting of the vapor with the hand toward the nose is recommended. Known toxic substances should always be confined to the fume hoods. 2. Under no condition should mouth pipeting be practiced. A suction bulb or syringe-like device will be provided for all pipeting. 3. Acids are frequently utilized in the lab. The proper procedure for mixing acids and water is to pour the acid into the water, not the other way around. Most acids generate large quantities of heat when mixed with water and set up the potential for spraying hot acid all over. If the denser acid is added to the less dense water, the acid will sink to the bottom of the container, lessening the chance of splatter. Equally important is the fact that if the water is poured into the acid there is potentially more acid available to be splattered. 4. Because corrosive chemicals will be added to glassware, and often the glassware will be heated strongly, always check the glassware for chips or cracks that may cause the glassware to break upon heating. Return cracked glassware to the stockroom for disposal. 5. Disposal of waste in the laboratory is a problem of which we all must be aware. Solid waste such as metal samples, litmus paper, and insoluble precipitates belong in the trash can (or other specified receptacle when special solid chemical wastes are encountered). They are not to be placed in the sinks. Liquid wastes and small amounts of water soluble solids are to be flushed down the sinks with a lot of water to insure adequate dilution. Special instructions will be given for the disposal of liquid organic wastes (do not flush them down the sink). If you have any doubt, check with the lab instructor. 6. Good housekeeping is an integral part of any experiment. You are responsible for keeping the balance and side shelf areas as well as your own lab bench work space clean. Wipe up spilled solids or liquids immediately. To help prevent spills and avoid contamination, always replace the lids or caps on reagent bottles. Any equipment obtained from the equipment bench or side shelf should be cleaned and returned there at the end of the experiment. 7. And finally, before you leave the lab you should wash your hands thoroughly with soap and water. Make sure there are no other chemical contaminants on you or your clothing before you leave. If An Accident Occurs There are certain basic responses that you may be called upon to make should an accident occur. 1. The most common accident in the laboratory involves minor cuts encountered from broken glass. If you have an accident involving broken glass, have the storeroom attendant or lab instructor clean up the broken glass. They have the proper equipment to do the job. Don't unnecessarily risk being cut cleaning up the glass because you are in a hurry to get back to work. 2. If you are wearing your safety glasses (ON YOUR EYES, NOT ON TOP OF YOUR HEAD OR AROUND YOUR NECK), there should never be an accident where something gets into your eye. Nevertheless, you are responsible for knowing the location and operational procedure for the eyewash facility in your lab. The basic rule is to flush your eye(s) with copious amounts of water should this type of accident happen.

3 SAFETY Page 3 3. Large chemical spills must always be handled by the lab instructor, unless they spill on you. In this event immediate action by you or those around you is essential. Each laboratory is equipped with a safety shower. It is to be used in the event a large amount of chemical comes in contact with your body. IMMEDIATELY GET UNDER THE SHOWER AND PULL THE RING THAT WILL RELEASE LARGE QUANTITIES OF WATER. WHEN YOU LET GO OF THE RING, THE FLOW OF WATER WILL STOP. The effect of the chemical must be diluted quickly to minimize the harm to your body. Small amounts of acids or bases, however, are spilled quite often in routine laboratory work and do not require such drastic measures. Still, the first reaction is to thoroughly rinse the spill off with water. Chemical spills other than acids or bases should be handled by the lab instructor. 4. If a fire breaks out, a determination must be made as to the proper action you should take. In the general chem lab most fires are of a nature that they can be extinguished by smothering them with anything handy, a towel, a handkerchief, or even a notebook. If you leave them unattended, they naturally will grow. If there is a large fire, immediately call the lab instructor for help. The lab instructor will make any decision about further action or evacuation of the lab. Everyone in the lab is responsible for knowing the location of the fire extinguishers and the proper procedure for their use. AIM THE FIRE EXTINGUISHER AT THE BASE OF THE FIRE, pull the pin, and squeeze the trigger or handle mechanism. 5. All accidents must be reported to the lab instructor so that proper actions may be taken. For things beyond minor cuts, burns, or contact with small amounts of chemicals, you should make arrangements with the campus health center or your local physician for examination or treatment. Safety is our chief concern every time we enter the laboratory. It begins with knowledgeable preparation in order to prevent accidents. It involves safe and prudent procedures while conducting experiments. And, it presumes appropriate responses by all to any accident that might occur. Thoroughly familiarize yourself with the above policies and procedures. If you have any questions about the safety procedures, ask your lab instructor. During the first laboratory session you will view a safety video and be required to sign a safety agreement. When you first go to the laboratory, mark on the diagram below the location of the following: 1) Your lab work space 2) Eye wash station(s) 3) Safety Shower(s) 4) Fire extinguisher(s) Lab 305 Lab 314 Figure 1

4 Page 4 SAFETY Material Safety Data XYZ Chemical Company, 100 Main St., Anytown, USA Emergency Phone Number: (xxx) xxx-xxxx Fire Extinguishing Media: Water HYDROCHLORIC ACID (10-22%) or water spray. Neutralize with soda ash or slaked lime. PRODUCT IDENTIFICATION: Synonyms: Muriatic acid, hydrochloric acid diluted Molecular Weight: Chemical Formula: HCl Hazardous Ingredients: Hydrochloric acid PRECAUTIONARY MEASURES DANGER! Corrosive. Causes severe burns. May be fatal if swallowed. Harmful if inhaled. Do not get in eyes, on skin, or on clothing. Avoid breathing mist. Use with adequate ventilation. Wash thoroughly after handling. This substance is classified as a POISON under the Federal Caustic Poison Act. EMERGENCY/FIRST AID If swallowed, DO NOT INDUCE VOMITING! Give large quantities of water. Never give anything by mouth to an unconscious person. If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. In case of contact, immediately flush skin or eyes with plenty of water for at least 15 minutes. In all cases call a physician. --SEE SECTION 5. DOT Hazard Class: Corrosive Material SECTION 1 Physical Data Appearance: Clear, colorless liquid. Odor: Odorless. Solubility: Infinitely soluble in water. Boiling point: C ( F). Specific Gravity: ca Vapor Pressure (mmhg): No information found. SECTION 2 Fire and Explosion Fire: Not considered to be a fire hazard. May react with metals to release flammable hydrogen gas. Explosion: Not considered to be an explosion hazard. SECTION 3 Reactivity Data Stability: Stable under ordinary conditions of use and storage. Hazardous Decomposition Products: Emits toxic fumes of hydrogen chloride when heated to decomposition. Incompatibilities: A strong mineral acid, concentrated hydrochloric acid is highly reactive with strong bases, metals, metal oxides, hydroxides, amines, carbonates, and other alkaline materials. Incompatible with materials such as cyanides, sulfides, sulfites, and formaldehyde. SECTION 4 Leak/Spill Disposal Clean-up personnel should wear protective clothing and respiratory equipment suitable for toxic or corrosive fluids or vapors. Isolate or enclose the area of the leak or spill. Small spills: Neutralize with alkaline material (soda ash, lime, etc.) and flush with water. Larger spills: Provide forced ventilation to dissipate fumes. Neutralize with alkaline material, pick up with absorbent material (sand, earth, vermiculite). Dispose of in an RCRAapproved waste facility. SECTION 5 Health Hazard A. EXPOSURE/HEALTH EFFECTS Inhalation: Corrosive! Inhalation of vapors can cause coughing, choking, inflammation of the nose, throat, and upper respiratory tract. Ingestion: Corrosive! Swallowing hydrochloric acid can cause immediate pain and burns of the mouth, throat, esophagus, and gastrointestinal tract. May cause nausea vomiting, and diarrhea. Skin contact: Corrosive! Can cause redness, pain, and severe skin burns. Concentrated solutions cause deep ulcers and discolor skin. Eye Contact: Corrosive! Vapors are irritating and may cause damage to the eyes. Splashes may cause severe burns and permanent eye damage B. FIRST AID Inhalation: Remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Call a physician. Ingestion: DO NOT INDUCE VOMITING! Give large quantities of water or milk if available. Never give anything by mouth to an unconscious person. Get medical attention immediately. Skin Exposure: In case of contact, immediately flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing and thoroughly clean shoes before reuse. Get medical attention immediately. Eye Exposure: Wash eye with plenty of water for at least 15 minutes, lifting lower and upper eyelids occasionally. Get medical attention immediately. C. TOXICITY DATA (RTECS, 1986) Hydrochloric acid: Inhalation rat LC50: 3124 ppm/1h Oral rabbit LD50: 900 mg/kg Mutation references cited SECTION 6 Occupational Control Measures Eye Protection: Use chemical safety goggles and/or a full face shield where splashing is possible. Contact lenses should not be worn when working with this material. Maintain eye wash fountain and quick-drench facilities in work area. Airborne Exposure Limits: OSHA Permissible Exposure Limit (PEL): 5 ppm (TWA) Ceiling SECTION 7 Storage and Special Store in a tightly closed container in a cool, dry, ventilated area. Protect against physical damage. Isolate from incompatible substances.

5 SAFETY Page 5 An important source of information regarding the safe storage and handling of chemicals as well as on the appropriate response to an accident involving chemicals are the Material Safety Data Sheets (MSDSs) which producers or suppliers of chemicals are required by law to provide to purchasers or users. Although there is no standard form for the MSDS, certain data must be present. On the facing page is an abbreviated MSDS for diluted (3-7 M) hydrochloric acid. In the interest of clarity, some of the more detailed or technical information has been omitted. Your instructor can show you examples of actual MSDSs. The first required piece of information is the name, address and phone number of the source of the information. This is usually the manufacturer or supplier of the chemical. Next is the product identification. This includes not only the chemical name and formula, but also any synonyms, common names, or trade names. For example, brick masons use hydrochloric acid to clean excess mortar from bricks, but they refer to it as muriatic acid. In the case of a mixture, all potentially hazardous components must be listed along with their percent by weight or volume. The next two sections in our example MSDS are probably the most important for you: "Precautionary Measures" for safe handling of the material and "Emergency First Aid" in case of an accident. This same information is repeated and expanded upon in the Section 5 on Health Hazards. Also important is the Occupational Control Measures. These refer to items normally available in any properly operated chemical laboratory: eye wash fountains, quick drench facilities (safety showers), as well as personal protection in the form of safety goggles. Note the comment regarding contact lenses. Most of the remaining information will be primarily of interest to your instructor or laboratory manager, as it deals with conditions of storage and response to fire or major accidents. Incompatible substances are those which react vigorously with one another or which produce toxic products when they react. Such materials should not be stored in close proximity to one another to avoid the possibility of a violent or hazardous reaction should there be an earthquake, fire, or other major accident. There are several abbreviations/acronyms used with which you should become familiar. OSHA is the Occupational Safety and Health Administration which is responsible for ensuring safety in the workplace. RCRA is the Resource Conservation and Recovery Act which includes provisions governing the disposal of hazardous wastes. PEL is the Permissible Exposure Limit (ppm is parts per million). LC50 and LD50 are measures of exposures which produce death in 50% of the animals used in the toxicological tests. Thus, an airborne concentration of 3124 ppm (600 times the PEL) for 1 hour resulted in the eventual death of 50% of the rats used in the test, while administration by mouth of 900 mg per kilogram of body weight to rabbits likewise produced death in 50% of the animals (Further details of the toxicological testing would be available in the reference RTECS, 1986).

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