chemical hazard what is a chemical hazard?

Post on 18-Jan-2018

243 Views

Category:

Documents

4 Downloads

Preview:

Click to see full reader

DESCRIPTION

Chemical Hazards Physical Health

TRANSCRIPT

Chemical hazard

What is a Chemical Hazard?

Any chemical that can cause illness, injury, or an emergency.

Chemical Hazards

Physical Health

Chemical health hazard

Irritants Corrosives Sensitizer Target-Organ Chemicals

Nephrotoxins Hepatotoxins NeurotoxinsAgents

which act on the blood

Agents which

damage the lungs

Eye hazards

Reproductive Carcinogens

Physical hazard

Fire hazard

pyrophorics oxidizersflammabl

eCombustible

s

Explosive Reactive chemicals

Water reactive Unstable

Chemical Health Effects

Irritants: Inflame skin or eye tissues on contact.

Corrosives: Destroy skin tissue at point of contact.

Sensitizers: Cause allergic reactions in normal tissue after exposure.

Target-Organ Chemicals: Damage specific body organs and systems.

Reproductive Hazards: Change genetic information in egg or sperm

cells and/or damage fetus after conception.

Carcinogens: Cause cancer.

 .Is the inflammation results from concentrations low

concentration (far below those needed to cause corrosion). 

Common irritants include substances such as: 1. ammonia2. alkaline dusts and mists3. epoxy resins4. ozone 5. nitrogen dioxide6. phosphorus chloride

Irritants

2 -Corrosive

Visible damage, or irreversible damage to body tissue Acids

Caustics (or bases)

Hydrochloric acid, sulfuric acid, nitric acid

pH Scale

1 147Acids

Caustics (or bases)

3-Target organ effect

Agents which act on the blood4

Hepatotoxins1

Neurotoxins 3

Nephrotoxins2

Agents which damage the lungs5

Eye hazards6

Chemicals which produce liver damage

Example : Carbon Tetrachloride, nitrosamines

1 -Hepatotoxins

2-Nephrotoxins

Chemicals which produce kidney damage

Examples: Halogenated Hydrocarbons, uranium

3 -Neurotoxins

Chemicals which produce their primary toxic effects on the nervous system

Examples: Mercury, carbon disulfide, lead

5 -Agents which act on the blood

Decrease hemoglobin function, deprive the body tissues of oxygen

Examples : Carbon monoxide, cyanides

6 -Agents which damage the lungs

Chemicals which damage pulmonary tissue Signs and Symptoms: Cough, tightness in the chest, loss of breath

Chemicals: Asbestos (Mg3Si2O5(OH)4), silica

Reproductive Hazards

• Chemicals which damage reproductive capabilities

• Includes chromosomal damage (mutations) and

damage to fetuses (teratogenesis)

• Signs and Symptoms: Birth defects, sterility

• Chemicals examples: Lead

Carcinogens

A “carcinogen” commonly refers to any agent that can initiate or speed the development of malignant tumors

Carcinogens commonly used in significant quantities include formaldehyde (Formalin solutions), benzene, ethylene oxide, and chloroform.

physical health hazard

Fire hazard ExplosiveReactive chemicals

Flammable hazarded material• What are flammable and combustible liquids?• Flammable and combustible liquids are present in

almost every workplace. Fuels and many common products like solvents, thinners, cleaners, adhesives, paints, waxes and polishes may be flammable or combustible liquids

What is a flashpoint?

The flashpoint of a liquid is the lowest temperature at which the liquid gives off enough vapors to be ignited (start burning)

Flammable Chemicals• Examples: diethyl ether, acetone, hexanes, ethanol,

methanol• flammability rating is given by a number 4-0 in• flammability rating of diethyl ether is "4" while acetone, methanol, ethanol, and hexanes are "3". • Ether is extremely flammable and any spark or simply

heat can ignite it.• flammable liquid have Flashing point <22.8 0C• Combustibles liquid have Flashing point > 22.8 0C

flammable material Protection

• Never use ether in a lab that has an open flame anywhere in the room.

• Be careful not to spill any flammable solvent (especially ether) on a heating mantle or hot plate.

• Keep them away from electrical outlets.

A pyrophoric

• A pyrophoric substance ignites spontaneously in air at or below 55°C (130°F).Examples are iron sulfide and White phosphorus

• They can be handled safely in atmospheres of nitrogen.

• Most pyrophoric fires should be extinguished with a Class D fire extinguisher for burning metals.

Explosives • is a reactive substance that contains a great amount of

potential energy that can produce an explosion if released suddenly,

• Nitroglycerin: A highly unstable and sensitive liquid.• Acetone peroxide: A very unstable white organic peroxide.• TNT: Yellow insensitive crystals that can be melted and cast

without detonation.• Nitrocellulose: A nitrated polymer which can be a high or low

explosive depending on nitration level and conditions•

Reactive chemicals

A water-reactive substance is one that spontaneously undergoes a chemical reaction with water. Notable examples include lithium, sodium,

potassium, rubidium, and caesium

Unstable hazard : Radioactive material

oxidizing agent hazard • An oxidizing agent (also oxidant, oxidizer or oxidizer)

is the element or compound gaining electrons (and is thus often called an electron acceptor),

• Examples • Oxygen (O2)• Ozone (O3)• Hydrogen peroxide (H2O2) and other inorganic

peroxides• Fluorine (F2), chlorine (Cl2), and other halogens

What Should the Ideal Laboratory Look Like?

1. Equipment & Ventilation2. Safety Showers and Eyewashes3. Chemical Storage4. Match the Extinguisher to the Risk! 5. Means of Egress/Exit6. Material Safety Data Sheets(MSDS)

1 -Ventilation

General VentilationSupply Air Diffusers & Room Air Exhausts Should be Located So As to Avoid Intake of Contaminated Air

Windows Should be Operable

Local VentilationFume Hoods Used For Operations that Give Off:

Noxious OdorsFlammable or Poisonous Vapors

2 -Safety Showers and Eyewashes

Must Be Available in All Lab Areas That Use or Store Chemicals Which Are

Corrosive or an Irritant to the Eyes or Skin

Combination Eye Wash & Drench Hose Units at the Sink are Now Available

3 -Chemical Storage

Safe Storage of Chemicals is a Necessity in Every hospitals!

Minimizes Exposure to Staff to Corrosive and Toxic Chemicals

Lessens the Risk of Fire Prevents the Mixing of Incompatibles & the

Creation of an Emergency Situation

The “Don’ts” of Chemical Storage!

Avoid storing any chemical above eye level

Don’t store incompatible chemicals together

Don’t store chemicals near sources of heat or sunlight

Don’t store chemicals in the hoods or acids on metal shelves

Avoid storing anything on the floor, especially glass bottles

Ideal Storage Area Set-Up

AcidsNa, Li

Oxidizers

bases

Flammables CabinetSpill Materials

Dry Chemicals

Metal SaltsNitrates

Room Should Have:• Eye Wash• Safety Shower• Emergency Phone• Fire Extinguisher

4 -Match the Extinguisher to the Risk A for "Ash" Class A fires involve organic solids such as

paper and wood.

B for "Barrel" Class B fires involve flammable or combustible liquids, including petrol, grease, and oil

C for "Current" Class C fires involve electric current

D for "Dynamite" Class D fires involve combustible metals.

K for "Kitchen Oils and fats

5- Means of Egress/ Exit

Two or more well- marked & unobstructed evacuation exits are recommended in a lab.

6-Material Safety Data Sheets (MSDS)

• (MSDS) are one of the most important tools

• available to employers • for providing information, and protection• to workers from hazardous chemicals• which are used in the workplace.

Material Safety Data Sheets required information

• Identity of the chemical • Physical and chemical characteristics • Physical hazards• Chemical hazards• Primary routes of entry• exposure limits• Control measures• Emergency procedures• thechemical hazardous • Date of preparation• Name, address and telephone of the manufacturer

1 -organic solvent

2 -acids

3 -bases

4 -mercury

Be Prepared for Small Incidental Spills

Spills Chemical Categories

Proper Incidental Spill Control Equipment Includes:

Scoops, Brooms, Pails & Bags

Spill Control Materials Such As Spill Control Pillows, Pads, Booms, etc

Neutralizers – for Acids & Alkalis

Absorbent – such as Diatomaceous Earth

Mercury Spill Control Kit

Examples of spill cleanup materials include  :

• trisodium phosphate • sand • sodium bicarbonate for acids • powdered citric acid for bases • "Oil-Dri," "Zorb-All," "Speedi-Dri" • paper towels

Waste Chemical DisposalRequires:

Proper storage– same rules apply – make sure waste chemicals are compatibleProper labeling – Containers containing hazardous waste must be labeled with the words HAZARDOUS WASTE

Pre-planning – know what waste you’re creating prior to carrying out experimentsRecord-keeping – of all waste chemicals on hand and those already picked up for disposal

• 1- Give the names of the two chemical hazards.• 2. What name is given to a chemical which will

burst into flame when contacted by air?• 3. What is a health hazard?• 4. Which kind of health hazard destroys skin on

contact?• 5. Chemicals that cause sterility, fetal death, and

birth defects are called ____________.• 6. What is a carcinogen?• 7. Give the three states in which a chemical can

exist.• 8.What is an MSDS?• 9.What kind of information is found on the MSDS?

top related