LaboratorySafety Rules

DANGER

Wear the right clothing for lab work no

dangling jewelry

Chemical Burns

Chemical burns on feet.

Skin burned by chemicals

FlammableFlammable

ReactiveReactiveHealthHealth

SpecialSpecial

Basic Safety Rules

Use common sense.

No unauthorized experiments. No horseplay.Handle chemicals/glassware with respect.

Safety Features of the Lab

safety showerfire blanketfire extinguisher eye washfume hoodcircuit breaker switch

Safety Equipment

Fire ExtinguisherType A

Type B

Type C

Safety Goggles

Safety Shower

SAFETY in the Science Classroom

Obey the safety contract– Use common sense– No unauthorized experiments– Wear safety glasses– Safety is an attitude!– Don’t take anything out of lab– Read and follow all instructions

Material Safety Data Sheet (MSDS)

• Gives information about a chemical.

• Lists “Dos” and “Don’ts.”

Chemical Exposure

a one-time exposure causes damage

acute exposure chronic exposure

damage occurs after repeated exposure

How Toxic is “Toxic?”

• Flammable• Explosive• Radioactive• Corrosive• Irritant• Toxic

– Chronic toxicityChronic toxicity: low doses repeated over a long period of time

– Acute toxicityAcute toxicity: immediate effect of a substance as a result of a single dose

• “Lethal Dose 50%” LD50

Chemicals may cause harm in many different ways.

the lethal dosage for 50% of animals on which the chemical is tested

LD50

There are various ways an LD50 can be expressed. For example, acetone has the following LD50s:

ORL-RAT LD50: 5,800 mg/kg (orally in a rat)IHL-RAT LD50: 50,100 mg/m3-h (inhaled- rat)SKN-RBT LD50: 20 g/kg (on skin – rabbit)

Toxicity

Which is more toxic?

Chemical A: LD50 = 3.2 mg/kg Chemical B: LD50 = 48 mg/kg

Chemical A is more toxic because less of it proves fatal to half of a given population.

Lead Poisoning

LD50 = mg / kg

Effects: slow mental development lack of concentration

Small children may accidentallyingest lead-based paints that peel

off from window sills and walls.

Knowledge = Safety• Material Safety Data Sheet (MSDS)

– Lists hazards, special handling instructions, and risks associated with a material. Supplied by manufacturer.

• Acute Exposure – Single episode can cause great damage

• Chronic Exposure– Many episodes over a period of time cause

damage• Carcinogen – causes cancer• Mutagen – causes mutations (genetic defects)• Tetragen – causes birth defects• Neurotoxin – severely poisonous and toxic

Read chemical labels.

Follow the instructions and safety precautions stated on the labels.

If you have a spill on the floor or lab bench, call your teacher rather than trying to

clean it up by yourself.

Always report any accident to your teacher immediately.

NEVER take any chemicals out of the lab.

Chemistry labs are full of possible hazards and hazardous situations. Make sure your behavior does not make you a hazard to

yourself and others in lab.No Rough Housing or Horsing Around will be

Tolerated!!