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Chemical and reagenthazardsDr. Hafez Alsumairy

Diagnostic & Molecular Microbiology2014-2015

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Chemical hazards symbols

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Chemical hazardsClassification of flammable chemicals• Extremely flammable

• 0◦C Flash point• Diethyl ether

• Highly flammable• <21◦C Flash point• Absolute ethanol

• Flammable• =>21°C• Xylene

Safe storage and use of flammablechemicals• Storage

• Not over 500 ml amounts• In a closed steel or thick

plywood box• At ground level• Preferably in an outside locked

store that is cool and wellventilated

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Chemical hazardsSafe use• Well ventilated• No open flame within 2-3

meters• Tightly closed• Use a water bath

Control of fires involving flammableliquids• With a lid or a fire blanket• Dry powder chemical fire

extinguisher• Dry sand

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Chemical hazardsOXIDIZING CHEMICALS• An oxidizing substance is one

that produces heat• Hydrogen peroxide• Potassium permanganate

Safe storage and use of oxidizingchemicals• Storage

• Away from flammable substancesand reducing agents

• Safe use• Dangerous to skin and eyes

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Chemical hazardsTOXIC, HARMFUL AND IRRITATINGCHEMICALS• A toxic substance is one that can

cause serious acute or chroniceffects, even death

• A harmful substance is one thatcan cause limitedeffects on health

• An irritating chemical is one thatcan cause inflammation andirritation

Safe storage and use of toxic,harmful and irritating chemicals• Storage

• Safely in a cupboard, not on an openshelf

• Safe use• Wash the hands• Eyewash bottle• Always lock away• In a fume cupboard• place a cloth over the neck of the

container and cap• Tightly closed• Never mouth-pipette

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Chemical hazardsCORROSIVE CHEMICALS• A corrosive chemical can destroy

living tissue and is also capableof damaging inanimatesubstances.

• Sodium hydroxide

Safe storage and use• Storage

• At low level• Safe use

• Never mouth-pipette• Poured at below eye level, slowly• Protective gloves and a face visor

or at least eye shields• Dissolve a solid chemeical with great

care• NEVER ADD WATER TO ACID

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Chemical hazardsEXPLOSIVE CHEMICALS• Heat, flame, knocks or friction

can cause explosive chemicals toexplode

SAFETY GUIDELINES FOR COMPRESSEDAND LIQUEFIED GASES• Cylinders are clearly labelled• warning notices on the doors• Do not keep more than one cylinder• Fix securely (e.g. chain) a gas cylinder to

the wall• Do not locate near to other heat sources• Turn off the main high-pressure valve• Use a trolley• Do not incinerate single use gas cylinders

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Equipment and glasswarehazards

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PREVENTING EQUIPMENT RELATEDACCIDENTS

1. Safe positioning andinstallation of equipment• Consider both safety and

convenience• Make sure ventilation is adequate• Use a qualified electrician and

follow the manufacturer’sinstructions

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PREVENTING EQUIPMENT RELATEDACCIDENTS

3. Cleaning, maintenance,inspection and servicing ofequipment• Maintenance and servicing• Hold stocks of essential

components

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2. Safe use of electricalequipment• Manufacturer’s instruction manual

written in a language• Use the equipment correctly• Make sure staff are well instructed

Preventing equipment relatedaccidents

3. Safe management ofbreakages• Wear heavy duty gloves and use

forceps• Discard in a separate puncture

resistant waste bin• Never leave used capillary tubes• Immediately collect• Wear suitable closed toe footwear• Inspect regularly places• Treat immediately any glass injury

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1. Correct purchasing ofglassware• Avoid purchasing glassware

classified as ‘disposable• Made from Pyrex or other heat

resistant glass2. Safe handling of glassware

• Use appropriate plastic containers• inspect glassware• Wear protective gloves• Store glassware safely• Use racks or trays

Fire safety

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Fire fighting equipment

• Buckets of water to extinguish paper, fabric and wood fires• Buckets of sand or dry soil.• Fire blanket(s) made from heavy cotton twill treated with a fire

retardant chemical• Dry powder chemical fire extinguisher to extinguish electrical fires

and fires caused by flammable liquids.

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Thank you

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