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Glassware is designed for a specific purpose. It should only be used for that purpose. "Makeshift" apparatus may be unstable and could lead to accidents and injuries.

When selecting glassware, determine the compatibility of the glassware with the chemicals or process. Some chemicals react with glass or cause damage (etch) glass. If your process involves temperature or pressure changes, ensure the glassware can withstand the changes. 

Examples of chemical compatibility and glassware to keep in mind:

• Heat causes expansion of volatile materials. Confinement of expansion results in explosion. Danger exists even if external heat is not applied.
• Mixing sulfuric acid with water inside a cylinder causes an exothermic reaction to occur, resulting in the heat from the reaction to break the bottom of the vessel. Never mix sulfuric acid inside a cylinder.
• Hydrofluoric acid chemically attacks glass. Hot phosphoric acid and strong hot alkalis also attack glass. Never use glass to contain these processes.

Before working with glassware, always inspect it for flaws. If defects are discovered, glass should be removed from service. Scratches in glass can grow to cracks later on. Dispose of flawed glassware if repairs are not possible.

Setting up apparatus can involve pushing glass tubes through a cork or stopper.  Researchers may also attach a rubber policeman to a glass rod. Sometimes researchers will attach a glass pasteur pipette to rubber tubing for aspiration.  All of these procedures have a high risk of injury to your hands if the glass tube, rod, or pipette break. 

When handling glass rods, tubes, or pipettes remember the following:

• Determine the holes are the correct size for the glass material.
• Never force the glass into place.
• Lubricate the hole and tube.  Water, soapy water, or glycerin may be used a lubricant.  It is not advised to use oil or grease.
• When possible, wear cut resistant gloves.
• Hold the glass material with a towel.
• Position the glass material close to the insertion point.
• Gently twist the glass material into place.

Setting up apparatus can involve pushing glass tubes through a cork or stopper.  Researchers may also attach a rubber policeman to a glass rod. Sometimes researchers will attach a glass pasteur pipette to rubber tubing for aspiration.  All of these procedures have a high risk of injury to your hands if the glass tube, rod, or pipette break. 

When handling glass rods, tubes, or pipettes remember the following:

• Determine the holes are the correct size for the glass material.
• Never force the glass into place.
• Lubricate the hole and tube.  Water, soapy water, or glycerin may be used a lubricant.  It is not advised to use oil or grease.
• When possible, wear cut resistant gloves.
• Hold the glass material with a towel.
• Position the glass material close to the insertion point.
• Gently twist the glass material into place.

• Check with the glassware manufacturer to determine safe temperature usage. Most glassware can only be exposed to certain high and low temperatures. Usage outside of those ranges may cause damage or breakage to the glassware.
• Always watch evaporation closely. A vessel, heated after evaporation has already occurred, may crack.
• Do not put hot glassware on cold or wet surfaces as it may break with temperature change.
• Never heat glassware that is etched, cracked, chipped, nicked or scratched.
• Glassware with thick walls (e.g. bottles and jars) should never be heated over a direct flame. Additionally, do not heat glassware directly on electrical heating elements.
• Do not look down into a vessel being heated.
• Cool all glassware slowly to prevent breakage, unless using specifically designed glassware.
• Use care when removing glassware from ultra-low temperature freezers (-70 to -150 C) to prevent thermal shock and cracking. For best results, immediately rinse the entire bottle under cold running water until thawing begins. Never place bottles directly from the freezer into warm water baths.
• When using a bunsen burner, the flam should touch the glass below the liquid level. A ceramic-centered wire gauze will diffuse the burner flame to provide more even heat.
• Always use hotplates that are larger than the bottom of the vessel being heated. Thick-walled glassware (e.g. jars, bottles, cylinders, and filter flasks) should never be heated on hot plates.
• When using a hot/stir plate, ensure that only the settings necessary are activated (i.e. if you do not intend to heat, ensure the hot plate is NOT turned on.

Good lab technique necessitates the use of clean glassware. Glass must be physically clean, chemically clean, an in many cases, sterile. Many glassware accidents occur during cleaning. Some reminders when washing and drying glassware.

• Eye protection and heavy-duty slip-resistant and chemically resistant gloves should be worn when washing glassware.
• Wash glassware as quickly as possible after use. The longer it is left unwashed, the harder it will be to clean. If necessary, allow harder to clean apparatus to soak in soapy water.
• Do not overload sinks, dishwashers, or soaking bins.
• Keep glassware clear of the sides of the sink. Rubber sink and counter mats can also help reduce the risk of breakage and injury.
• Never use worn out cleaning brushes; they can scratch or abrade the glass.
• Specialized training in the safe usage of caustic cleaning agents must be completed before using aqua-regia, chromic acid or other reactive solutions to clean glassware.
• When drying glassware, place articles on towels, lined basket, or slip-resistant pads. Be sure to place away from the edge of the bench. Large containers may be hung on pegs to dry.
• When cleaning pipettes, place pipettes, tips down, into a cylinder or tall jar of water or appropriate disinfectant (e.g. for biologically contaminated tips). A pad of cotton or glass wool at the bottom will help prevent breakage of the tips. Ensure the water or disinfectant level is high enough to immerse the pipettes.
• New glassware should be washed before use to remove any residue or loose particles.

Spills and Broken Glass

Glass is fragile and breaks easily. When glass breaks, care should be taken to reduce the risk of cuts.

• If something is falling, let it drop! Catching it may cause the glassware to break in your hand.
• Wear cut-resistant gloves when handling broken glass. Disposal nitrile or latex gloves should NEVER be worn. Glass will cut through those gloves.
• When cleaning broken glass, use mechanical means to pick up the pieces.
• Tongs, tweezers, or forceps should be used to pick up large pieces of broken glass.
• Small shards can be picked up using a wet paper towel or absorbent pad or by using rolled-up tape.

Proper Disposal

Ensure that others aren't injured by improperly disposed of broken glass.

Contaminated broken glass biological sharps container

• Place in rigid, puncture-resistant container (e.g. sharps container).
• For biologically contaminated broken glass, closed and sealed container should be placed in biohazardous waste box for disposal.
• For chemically contaminated broken glass, closed and sealed containers should be tagged as chemical waste.

Uncontaminated broken glass may be disposed of in a broken glass box or uncontaminated waste box.