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Hazard symbols

Cut out and stick the following hazard symbols in your book. Write out what you think is the correct meaning next to each. Choose from the list in the box below"

Biohazard
Corrosive
Harmful
Flammable
Irritant Oxidising
Radioactive
Toxic

Description:
The skull and crossbones mean that the substance is poisonous. These substances can cause death if swalled, breathed in or absorbed by the skin.

Precautions:
Anyone using a toxic chemical should wear gloves and eye protection, and wear a mask over their mouth and nose or handle the chemical in a fume cupboard.

Examples:
Chlorine gas, mercury, chromium oxide, lead and many lead compounds would be labelled with the toxic symbol.
Toxic or poisonous
toxic.png
Description:
These substances will burn skin or eyes on contact, or the throat and stomach if swallowed.

Precautions:
Anyone usingg a corrosive substance must wear gloves and eye protection.

Examples:
Concentrated solutions of strong acids such as sulphuric acid would be labelled with the corrosive symbol. Concentrated solutions of strong alkalis such as sodium hydroxide would also be labelled this way.
Corrosive
Corrosive.png
Description:
The substance (or its fumes) easily catches fire if placed near heat, sparks or flame.

Precautions:
Highly flammable substances pose a fire risk so these products must be kept away from sources of ignition and oxidising substances. Users must wear protective clothing and goggles.

Examples:
Ethanol (alcohol), methanol, hydrogen, propanone, petrol and methylated spirits would carry the highly flammable symbol.
Highly flammable
Flammable.gif
Description:
Not as dangerous as poisonous substances but can cause illness or irritation if swallowed or absorbed by the skin.

Precautions:
Users should wear eye protection and avoid breathing in any powders or fumes. Avoid contact with the skin and clean up any spills immediately.

Examples:
Harmful substances include copper chloride, copper sulphate, lead nitrate, lead oxide, sodium chlorate (weed killer).
Irritaants include caalcium chloride, calcium hydroxide, zinc sulphate, household bleach.
Harmful or irritant
harmfulirritant.png
Description:
As they can liberate oxygen at room temperature, oxidising substances fuel combustion, maintaining or even inductin fires by reacting with flammable materials.

Precautions:
Keep away from flammable chemicals at all costs! Wear eye protection and avoid contact with clothing, which is itself potentially flammable.

Examples:
Hydrogen peroxide, potassium manganate and sodium chlorate (weedkiller) would be labelled with the oxidising symbol. Nonoxygen containing oxidants include chlorine and bromine.
Oxidising
Oxidizing.png
Description:
Explosive substances release large amounts of energy very quickly when ignited by a flame or a spark. A sudden knock or friction may also cause the substance to explode.

Precautions:
These substances are usually stored in strong blast-proof containers. This reduces the risk of fire, limits possible damage and protects people who may be nearby.

Examples:
Fireworkds and flares. Dynamite, ammonium and TNT.
Explosive
explosive.gif
Description:
An environmental hazard is a general term for any situation that poses a threat to the surrounding environment, habitat or natural resources.

Precautions:
Industry and individuals must minimise their use of non-renewable energy sources and reduce the dumping of waste products and toxic materials.

Examples:
A chemical spill, an oil leak, dumping rubbish, emissions of pollutants or the leaching of pesticides and fertilizers.
Environmental Hazard
Environmental_Hazard.png
Description:
Radioactive materials emit energetic particles which ionise the molecules in living cells. This can result in sickness (e.g. hair loss and cancer) and genetic abnormalities in offspring. They are particularly hazardous if inhaled or swallowed.

Precautions:
Low activity sources should be stored in a lead-lined container, be handled with tongs and looked at by use of a mirror.

Examples:
Uranium, strontium, polonium, plutonium and many other elements have radioactive isotopes. Nuclear waste is highly radioactive and poses a big environmental problem.
Radioactive hazardRadioactive_Hazard.png
Description:
This symbol warns of an electric shock that is sufficient to kill ro burn.

Precautions:
Keep electrical equipment away from water and make sure your skin and clothing are dry when handling electrical products. Do not poke anything into electrical equipment or sockets. Never work alone with high voltage. if in doubt, don't touch.

Examples:
Keep away from pylons generators, train lines and electric meter cupboards. Exercise caution with anything connected to main s electricity. Even battery powered appliances containing capacitors can be dangerous.
Dangerous voltageHigh_voltage.png
Description:
Biohazardous material is defined as any material capable of causing disease or infection in healthy humans.

Precautions:
There are strict rules for containing and disposing of these substances (e.g. an agar dish hosting unidentified bacteria should be kept sealed and finally destroyed by incineration).

Examples:
Any bacterium, virus or toxin that is harmful to humans. Biological agents (such as anthrax or sarin gas) used in biological warfare.
Biohazard
Biohazard.png
Description:
Laser beams are fire hazards, but pose a particular risk of causing blindness or burning the skin. Lasers that emit ultraviolet or infrared light are especially dangerous because they aare invisible to the human eye.

Precautions:
You must always use protective eyewear when working with posweful lasers. People have been blinded through accidental reflection of a laser beam (off a wrist watch or other shiny surface) into their unprotected eyes.

Examples:
Lasers rated above class 2 pose a danger.
Laser radiation / Radioactive
Radioactive_Hazard.png