Presentation on theme: "LABORATORY SAFETY While working in the science laboratory, you will have certain important responsibilities that do not apply to other classrooms. You."— Presentation transcript:
LABORATORY SAFETY While working in the science laboratory, you will have certain important responsibilities that do not apply to other classrooms. You will be working with materials and apparatus which, if handled carelessly or improperly, have the potential to cause injury or discomfort to someone else as well as yourself.
NFPA CHEMICAL HAZARD LABEL Least Serious 4 Most Serious 40 Flammable vapor which burns readily Substance is stable
NFPA CHEMICAL HAZARD LABEL Avoid water. May detonate with heat or ignition. Severe health risk. Burns readily. Diborane 4 34 W
Health Hazard 4 Very short exposure could cause death or serious residual injury even though prompt medical attention was given. 3 Short exposure could cause serious temporary or residual injury even though prompt medical attention was given. 2 Intense or continued exposure could cause temporary incapacitation or possible residual injury unless prompt medical attention is given. 1 Exposure could cause irritation but only minor residual injury even if no treatment is given.irritation 0 Exposure under fire conditions would offer no hazard beyond that of ordinary combustible materials.combustible
FLAMMABILITY 4 Will rapidly or completely vaporize at normal pressure and temperature, or is readily dispersed in air and will burn readily.normal pressure and temperatureair 3 Liquids and solids that can be ignited under almost all ambient conditions. 2 Must be moderately heated or exposed to relatively high temperature before ignition can occur. 1 Must be preheated before ignition can occur. 0 Materials that will not burn.
INSTABILITY Readily capable of detonation or of explosive decomposition or reaction at normal temperatures and pressures.explosivedecompositionnormal temperatures and pressures 3 Capable of detonation or explosive reaction, but requires a strong initiating source or must be heated under confinement before initiation, or reacts explosively with water.explosivereacts explosively with water 2 Normally unstable and readily undergo violent decomposition but do not detonate. Also: may react violently with water or may form potentially explosive mixtures with water.decompositionreact violently with waterexplosivemixtures 1 Normally stable, but can become unstable at elevated temperatures and pressures or may react with water with some release of energy, but not violently.react with water with some release of energy 0 Normally stable, even under fire exposure conditions, and are not reactive with water. 1 Prior to 1996, this section was titled "Reactivity". The name was changed because many people did not understand the distinction between a "reactive hazard" and the "chemical reactivity" of the material. The numeric ratings and their meanings remain unchanged.
OX This denotes an oxidizer, a chemical which can greatly increase the rate of combustion/fire.oxidizerchemicalcombustion Unusual reactivity with waterUnusual reactivity with water. This indicates a potential hazard using water to fight a fire involving this material. This section is used to denote special hazards. There are only two NFPA 704 approved symbols
ACID This indicates that the material is an acid, a corrosive material that has a pH lower than 7.0acidcorrosive materialpH ALK This denotes an alkaline material, also called a base. These caustic materials have a pH greater than 7.0basepH This denotes a material that is corrosive (it could be either an acid or a base).corrosive The skull and crossbones is used to denote a poison or highly toxic material.poisonhighly toxic The international symbol for radioactivity is used to denote radioactive hazards; radioactive materials are extremely hazardous when inhaled.inhaled Indicates an explosive material.explosive
1. Beaker Beakers hold solids or liquids that will not release gases when reacted, or are unlikely to splatter if stirred or heated. Very poor to measure volume with (+/-5%) accuracy Note the size capacity (250 mL in this case)
2. Erlenmeyer Flask Erlenmeyer flasks hold solids or liquids that may release gases during a reaction or that are likely to splatter if stirred or heated. Note the size
3. Florence Flask Rarely used in first year chemistry, it is used for the mixing of chemicals. Narrow neck prevents splash exposure.
4. Graduated Cylinder A graduated cylinder is used to measure volumes of liquids – probably your best everyday measuring tool. Note the rubber “bumpers”, and also the size. Others that are smaller may not have “bumpers”, but have reinforced glass.
5. Test Tubes 18 x 150 mm 13 x 100 mm Ignition Tube (25 x 200 mm) Test tubes are used to mix chemicals, and also to heat chemicals.
6. Test Tube Holder A test tube holder is useful for holding a test tube which is too hot to handle. Knowing where to hold this piece of equipment is important.
7. Test Tube Brushes Test tube brushes are used to clean test tubes and graduated cylinders. Forcing a large brush into a small test tube will often break the tube. Don’t worry about drying the inside of a test tube. Small test tube brush Large test tube brush
8. Test Tube Racks Test tube racks are for holding and organizing test tubes on the laboratory counter.
9. Rubber Stoppers Rubber stoppers (also cork) are used to close containers to avoid spillage or contamination. Containers should never be heated when there is a stopper in place.
10. Well Plates Well plates are used when we want to perform many small scale reactions at one time. It is like having lots of test tubes available at one time.
11. Watch Glass A watch glass is used to hold a small amount of solid, such as the product of a reaction. Can also be used as a cover for an evaporating dish or beaker.
12. Stirring Rod The stirring rod is used to: a) manually stir solutions; b) assist in pouring liquids; and c) to transfer a single drop of a solution. Rubber policeman tip is used to remove precipitates. Stir with this end.
13. Dropper Pipet A dropper pipet is used to transfer a small volume of liquid, usually one drop at a time. On top of each dropper is a “rubber bulb” – never put your mouth on the dropper to provide suction
14. Funnel A funnel is used to aid in the transfer of liquids from one vessel to another, and will hold filter paper while filtering.
15. Graduated Pipet A graduated pipet measures and delivers exact volumes of liquids – uses a rubber bulb for suction (not your mouth).
16. Wash Bottle A wash bottle has a spout that delivers a water stream to a specific area. Distilled water is the only liquid that should be used in a wash bottle During use, keep the bottle upright as shown, since ours have a tube that goes to the bottom of the bottle. Distilled Water
17.Electronic Balance Electronic balances are very accurate, highly dependable, and rugged. The digital display makes the mass value very easy to determine. “On” button “Off” button “Tare” button Place item here to mass
18.Spatula Spatulas are used to dispense solid chemicals from their containers. Chemicals should never be transferred with your bare hands.
19.Beaker Tongs Beaker tongs are used to move beakers containing hot liquids. Note the rubber coating to improve grip on the glass beaker - do not hold this in a burner flame.
20.Burner Burners are used for the heating of nonvolatile liquids and solids. Hot plates will be used to gently heat any flammable chemicals.
21. Evaporating Dish The evaporating dish is used for heating stable solid compounds and elements, as well as for evaporating nonvolatile solutions.
22. Crucible and cover Crucibles are used for heating certain solids, particularly metals, to very high temperatures. The cover can be used to contain any smoke particles.
23. Clay Triangle The clay triangle is used as a support for crucibles when being heated over a lab burner. It can also be used to support a funnel when filtering.
24. Crucible Tongs For handling hot crucibles; also used to pick up other hot objects - NOT to be used for picking up beakers!
25. Ringstands Ringstands are a safe and convenient way to perform reactions that require heating using a lab burner. Can also be used as an insulating pad to place hot objects while they cool.
Ringstands and their components 26. Ring Clamp Ring clamps connect to a ringstand, and provide a stable, elevated platform for a beaker to be heated. Will also hold a clay triangle and funnel during filtering.
Ringstands and their Components 27. Test tube Clamps Test tube clamps are used to secure test tubes, distillation columns, and burets to the ringstand.
Ringstands and their Components 28. Double Buret Clamps Double Buret clamps are used to secure burets (long graduated tubes used in titrations) to the ringstand.
Ringstands and their Components 29. Wire Gauze Wire gauze sits on the iron ring to provide a place to stand a beaker. On older wire gauze, the white material was asbestos – currently it is a ceramic.
30. Lighter These strikers are used to light lab burners. The flints on strikers are expensive. Do not operate the striker repeatedly just to see the sparks!
31. Weighing Paper Used to measure small amount of solids. Never place chemicals directly onto the balance.
32. Hot Plates Used to “gently” heat liquids. We can’t regulate the heat In ours. To avoid spills, remove beaker or flask using tongs and place it on the lab desk.
33. Triple Beam Balance Used for weighing solids, liquids and powders.
34. Mortar and pestle Used to grind solids into powders