Pengurusan Makmal Sains 7

UNIT 7 : SAFETY IN SCIENCE LABAROTORY

UNIT 7 : SAFETY IN SCIENCE LABORATORY Concept mapping Safety in science laboratory

General guidelines in laboratory

7.1

7.2

First aid during emergency

First aid equipment

Objective 7.1.1

To let teacher know the safety in the lab

7.1.2

To expose the teacher about the first aid during emergency case in laboratory

Introduction Science is a hands-on laboratory class. You will be doing many laboratory activities

which require the use of hazardous chemicals. Safety in the science classroom is the #1 priority for students, teachers, and parents. To ensure a safe science classroom, a list of rules has been developed and provided to you in this student safety contract. These rules must be followed at all times. Two copies of the contract are provided. One copy must be signed by both you and a parent or guardian before you can participate in the laboratory. The second copy is to be kept in your science notebook as a constant reminder of the safety rules. Proper laboratory technique is essential to the education of successful scientist. Your success will depend on your attitude and conduct. If you work with an attitude of rushing through, you will profit but little. An interest in your work, an understanding of its purpose and a clear interpretation of your results are 75

UNIT 7 : SAFETY IN SCIENCE LABAROTORY

necessary factors for a good laboratory course. The chemistry laboratory is a safe place to experiment if your are careful. You must assume responsibility of the safety of yourself and your neighbors. Following are some safety and procedural rules to help guide you in protecting yourself and others from injury in the laboratory.

7.3

Safety in laboratory 7.3.1 General guidelines There are several tips that all science teacher should concern. Conduct yourself in a

responsible manner at all times in the laboratory. Be familiar with your lab assignment before you come to lab. Follow all written and verbal instructions carefully. If you do not understand a direction or part of a procedure, ask the teacher before proceeding. Never work alone. No student may work in the laboratory without an instructor present. When first entering a science room, do not touch any equipment, chemicals, or other materials in the laboratory area until you are instructed to do so. Do not eat food, drink beverages, or chew gum in the laboratory. Do not use laboratory glassware as containers for food or beverages. Perform only those experiments authorized by the instructor. Never do anything in the laboratory that is not called for in the laboratory procedures or by your instructor. Carefully follow all instructions, both written and oral. Unauthorized experiments are prohibited. Safety goggles and aprons must be worn whenever you work in lab. Gloves should be worn whenever you use chemicals that cause skin irritations or need to handle hot equipment. Wear older clothes that cover the maximum amount of skin. Observe good housekeeping practices. Work areas should be kept clean and tidy at all times. Bring only your laboratory instructions, worksheets, and/or reports to the work area. Other materials (books, 76

UNIT 7 : SAFETY IN SCIENCE LABAROTORY

purses, backpacks, etc.) should be stored in the classroom area.

Know

the

locations

and

operating procedures of all safety equipment including the first aid kit, eyewash station, safety shower, spill kit, fire extinguisher, and fire blanket. Know where the fire alarm and the exits are located. Be alert and proceed with caution at all times in the laboratory. Notify the instructor immediately of any unsafe conditions you observe. Dispose of all chemical waste properly. Never mix chemicals in sink drains. Sinks are to be used only for water and those solutions designated by the instructor. Solid chemicals, metals, matches, filter paper, and all other insoluble materials are to be disposed of in the proper waste containers, not in the sink. Check the label of all waste containers twice before adding your chemical waste to the container. Cracked or broken glass should be placed in the special container for “Broken Glass.” Labels and equipment instructions must be read carefully before use. Set up and use the prescribed apparatus as directed in the laboratory instructions provided by your teacher. Keep hands away from your face, eyes, mouth, and body while using chemicals. Wash your hands with soap and water after performing all experiments. Clean (with detergent powder), rinse, and dry all work surfaces and equipment at the end of the experiment. Experiments must be personally monitored at all times. You will be assigned a laboratory station at which to work. Do not wander around the room, distract other students, or interfere with the laboratory experiments of others. Students are never permitted in the science storage rooms or preparation areas unless given specific permission by their instructor. Know what to do if there is a fire drill during a laboratory period; containers must be closed, gas valves turned off, fume hoods turned off, and any electrical equipment turned off. 7.3.2

Clothing

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Any time chemicals, heat, or glassware are used, students will wear laboratory goggles. There will be no exceptions to this rule! Contact lenses should not be worn in the laboratory unless you have permission from your instructor. Dress properly during a laboratory activity. Long hair, dangling jewelry, and loose or baggy clothing are a hazard in the laboratory. Long hair must be tied back and dangling jewelry and loose or baggy clothing must be secured. Shoes must completely cover the foot. No sandals are allowed. 7.3.3

Accidents and Injuries

Report any accident (spill, breakage, etc.) or injury (cut, burn, etc.) to the instructor immediately, no matter how trivial it may appear. If you or your lab partner are hurt, immediately yell out "Code one, Code one" to get the instructor's attention. If a chemical should splash in your eye(s), immediately flush with running water from the eyewash station for at least 20 minutes. Notify the instructor immediately. 7.3.4 Handling Chemicals All chemicals in the laboratory are to be considered dangerous. Do not touch, taste, or smell any chemical unless specifically instructed to do so. The proper technique for smelling chemical fumes (when instructed to do so by the teacher) is to gently fan the air above the chemical toward your face. Breathe normally. Check the label on chemical bottles twice before removing any of the contents. Take only as much chemical as you need. Smaller amounts often work better than larger amounts.

Label all containers and massing papers holding dry

chemicals. ALWAYS ADD ACID SLOWLY TO WATER, with slow stirring and swirling, being careful of the heat produced, particularly with sulfuric acid. Handle flammable hazardous liquids over a pan to contain spills. Never dispense flammable liquids anywhere near an open flame or source of heat. Never take chemicals or other 77

UNIT 7 : SAFETY IN SCIENCE LABAROTORY

materials from the laboratory area. Take great care when transferring acids and other chemicals from one part of the laboratory to another. Hold them securely and in the method demonstrated by the teacher as you walk. 7.3.5 Handling Glassware and Equipment Inserting and removing glass tubing from rubber stoppers can be dangerous. Always lubricate glassware (tubing, thistle tubes, thermometers, etc.) before attempting to insert it in a stopper. Always protect your hands with towels or cotton gloves when inserting glass tubing into, or removing it from, a rubber stopper. If a piece of glassware becomes "frozen" in a stopper, take it to your instructor for removal. When removing an electrical plug from its socket, grasp the plug, not the electrical cord. Hands must be completely dry before touching an electrical switch, plug, or outlet. Examine glassware before each use. Never use chipped or cracked glassware. Never use dirty glassware. Do not immerse hot glassware in cold water; it may shatter. Report damaged electrical equipment immediately. Look for things such as frayed cords, exposed wires, and loose connections. Do not use damaged electrical equipment. If you do not understand how to use a piece of equipment, ask the instructor for help.

7.4

First aid in the Laboratory

7.4.1 Chemical Burns 7.4.1.1

Skin burns: 1. Remove the affected clothing of the injured person immediately. Do not forget to protect yourself from the contaminated clothing!

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UNIT 7 : SAFETY IN SCIENCE LABAROTORY 2. Rinse the burn immediately with plenty of water (for at least 10 minutes). Do not attempt to neutralise. 7.4.1.2

Eye burns: 1. Use an eye-wash basin or an eye-wash bottle to rinse the affected eye thoroughly with plenty of water. Take care to avoid washing any chemical into the uninjured eye. Whenever possible, rinse the whole eye, especially under the eyelid. Eye washing procedures are best executed by two persons, with help to the extent possible from the injured person, e.g., lifting the eyelid. 2. Bandage both eyes to keep the victim calm. 3. Always take the injured person to the eye clinic at the University Hospital. 4. Immediately cool the affected areas with cold, running water for at least 15 minutes. 5. Do not burst blisters. 6. Do not apply any cream, powder, oil or any other preparation to the burn or scald. 7. In the case of a burn to the face, joints, or genitals, or if you are uncertain about how to proceed, contact a doctor immediately, regardless of your assessment of degree of burn.

7.4.2 7.4.2.1

Poisoning Inhalation of poisonous gases, vapours, and aerosols: 1. Ensure your own safety by wearing respiratory protection (gas mask), then carry out the rescue by removing the injured person outside into fresh air.

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UNIT 7 : SAFETY IN SCIENCE LABAROTORY 2. If the injured person stops breathing, immediately apply mouth-to-mouth resuscitation; in case of cardiac arrest, apply cardiopulmonary resuscitation (CPR), if you are trained to do so. 3. If the injured person is conscious, he or she should sit upright; an unconscious victim should be arranged in the recovery position until medical assistance arrives. 7.4.2.2

Ingestion of poisons by mouth: 1. Any poisonous material must first be secured! Do not forget to protect yourself! 2.

Perform First Aid procedures according to the instructions of the toxicology centre (e.g., give the victim water, tea, activated charcoal, etc.). In the case of ingestion of strong acids, strong bases, or organic solvents, do not induce vomiting.

3. Keep the injured person lying down and warm. 4. Treat any ingestion of unknown chemicals as poisoning.

7.4.2.3

Poisoning by skin contact: 1. Remove the affected clothing of the injured person immediately. Do not forget to protect yourself from the contaminated clothing! 2. Rinse the affected areas with plenty of tepid water and gently wash with mild soap. Do not use hot water and do not rub excessively.

7.4.3

Open Wounds, Severe Injuries, and Bleeding

7.4.3.1 General bleeding:

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UNIT 7 : SAFETY IN SCIENCE LABAROTORY 1. Wear gloves when touching or rinsing the wound. Do not remove any foreign objects from the wound. 2. Cover the wound with a sterile dressing and apply a protective bandage. Disinfect only if no further medical treatment is necessary.

7.4.3.2 Heavy bleeding: 1. Have the patient sit or, preferably, lie down. 2. Raise the injured limb. 3. If heavy bleeding continues, apply pressure with your fingers (you must know the finger, arm, and head pressure points). 4. Apply a pressure bandage with a thick, absorbent dressing. 5. If one bandage is not sufficient, apply a second over the first. 6. Raise the injured limb and keep it still. 7. Watch for signs of shock! Keep the victim warm and calm. 8. Never use a tourniquet. If application of a pressure bandage is not possible, exert pressure directly on the wound.

7.5 First aid Box

7.5.1

Equipment

The first aid box should contain an instruction sheet giving general guidance, individually wrapped sterile adhesive dressings in a variety of sizes, sterile eye-pads with bandages for attachment, triangular bandages, sterile dressings for serious wounds, a

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selection of sterile unmedicated dressings for minor wounds, safety pins. A bottle containing eye drops, a first – aid manual. First-aid box must have these items;

7.5.2

•

Sodium carbonate, 5% solution

•

Sodium bicarbonate, 2% solution

•

Boric acid, saturated solution

•

Acetic acid. 5% solution

•

Cotton wool and gauze

•

Mercurochrome and tincture of iodine.

First aid measurement

1. Test plumbed eyewashes weekly; keep a log. 2. Remove chemical bottles from work area of Facilities personnel working in laboratories. 3. Stock first aid kits with Band-Aids, 4X4 gauze, roller bandages and ace bandages (no creams, ointments, etc.); report to Physician after first aid has been administered. 4. For Bleeding and Wound Care . Wear clean gloves. Cover area with gauze (or clean paper towels). Apply pressure to bleeding area -- have person sit or lie down. If wound is large or person is dizzy or weak, shift to hospital to Emergency Room. 5. Burns -- Heat/Chemical. Heat burns: -- run cool water over area for 5 minutes, then report to SHS; if burn area is large, cover with a cool, wet cloth and contact physician. Chemical burns (acid or alkaline) - flush with large amounts of cool running water for 15 minutes. For small area, report to SHS. For larger area or if person is weak or dizzy, contact physician. 76

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6. Eye Splash Chemical. Flush with lukewarm (body temperature) running water; turn head side to side and have water run across both eyes. Flush eyes for at least 15 minutes before going for further treatment at SHS or Emergency Room. 7. Eye - Foreign Body (dust or metal, paint, wood chips). Cover or close eye. Report to ophthalmologist. 8. DO NOT POUR ANY CHEMICALS DOWN SINK DRAINS OR SEWER GRATES. Call the hospital personnel for a NO-CHARGE chemical waste pickup.

7.6

Conclusion Accidents in the laboratory may have various causes: Acids and alkalis: splashes on the

skin or in the eyes, swallowing., Toxic substances, Heat: naked flames, hot liquids, flammable liquids, explosions, Injuries involving infectious material, electric shocks, etc. Look out for the various types of accidents involved and the various procedures that need to be followed and always consult the required medical personnel. Do not pour any chemicals down sink drains or sewer grates.

QUESTIONS: 1. What are the types of accidents encountered in laboratory? 2. What does the first aid equipment contain? 3. What are the contents of first aid box? 75

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ANSWERS: 1. Acids and alkalis, Toxic substances, Heat, and Injuries involving infectious material, electric shocks, etc. 2. First-aid box, Sodium carbonate, 5% solution, Sodium bicarbonate, 2% solution, Boric acid, saturated solution, acetic acid. 5% solution, Cotton wool and gauze, Mercurochrome and tincture of iodine. 3. The first aid box should contain the following; •

An instruction sheet giving general guidance

•

Individually wrapped sterile adhesive dressings in a variety of sizes

•

Sterile eye-pads with bandages for attachment

•

Triangular bandages

•

Sterile dressings for serious wounds

•

A selection of sterile unmedicated dressings for minor wounds

•

Safety pins

•

A bottle containing eye drops

•

A first – aid manual

References Amritage, Philip and Fasemore, Johnson. (1977). Laboratory Safety: A Science Teacher’s Source Book, Heinamann Education Books, London.

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Chisman, Dennis (1987) Preliminary Issues, Practical Secondary Education: Planning for Cost- Effectiveness in less Developed Countries, Commonwealth Secreteriat, London. Fahkru’l-Razi Ahmadun, Chuah Teong Guan and Mohd Halim Shah. 2005. Safety: Principles & Practices in the Laboratory, Penerbit Universiti Putra Malaysia, Serdang. Hegarty-Hazel, Elizabeth (1990), The Student Laboratory and the Science Curriculum: An Overview, The Student Laboratory and the Science Curriculum, pt.1, pg.3. McGrath, Dennis M. (1978), Some General Considerations, Laboratory Management and Techniques For School and Colleges, Anthonian, Kuala Lumpur-Ipoh-Singapore. Woolnough, Brian E. (1991). Setting the scene, Practical Science, pt.1, pg.6. Woolnough, Brian E. (1991). Setting the scene, Practical Science, pt.1, pg. 13. Woolnough, Brian E. (1991). Setting the scene, Practical Science, pt.1, pg. 14. K. Guy. Laboratory organization and administration. London Butterworths

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