Prof. Dr. Hülya YAVUZ ERSAN CHEMICAL SAFETY-I Prof. Dr. Hülya YAVUZ ERSAN

Chemicals Each year millions of workers are exposed to chemical hazards in worldwide. Chemical exposure may cause or contribute to many serious health effects such as heart ailments, central nervous system damage, kidney and lung damage, cancer, burns, and even death. With proper handling, even highly toxic chemicals can be used safely Less toxic chemicals can be extremely hazardous if handled improperly.

Chemical Hazard Chemicals have the ability to react when exposed to other chemicals or certain physical conditions. When chemical reactions are not properly managed, they can have harmful, or even catastrophic consequences, such as toxic fumes, fires, and explosions. These reactions may result in death and injury to people, damage to physical property, and severe effects on the environment.

Physical Hazards Associated to Chemicals Flammable - catches fire easily and burns rapidly Combustible - will burn under most conditions Explosive - will explode / detonate releasing hot gases Oxidizer - yields oxygen to enhance combustion, may cause ignition of combustibles with no external source of ignition Organic peroxide - uniquely hazardous, potentially explosive Unstable - tends to decompose during normal handling and storage Water reactive - reacts with water to release flammable gas, causes fire or presents a health hazard

Physical Hazards Associated to Chemicals Carcinogen - cause cancer or suspected to cause cancer Toxic Agent - poisonous / cause acute or chronic effects Reproductive toxin (teratogen) - could have harmful effect on male or female reproductive system or on developing fetus Irritant - can cause inflammation of skin or eyes Corrosive - cause irreversible damage to living tissue Sensitizer - cause exposed person to develop allergies to the substance Target organ-specific agents - hazardous to specific organs in body (e.g., dust/lungs, chloroform/liver, Pb/circulatory system, carbontetrachloride/kidneys, toluene/nervous system)

Route of entry Inhalation / breathing - most common route, gases / vapors can pass to blood, solid particles inhaled into lungs Absorption through the skin - many solids, liquids, vapors and gases can be absorbed through the skin Ingestion / swallowing - while not intentional, failure to wash hands, eating in contaminated lab, etc. Injection – accidental and inprope handling of glass and sharp objects, etc. Eye Contact - either physical damage or absorption The route of entry dictates selection of protective equipment

Working Safely with Chemicals To ensure that employers and employees know about work hazards and how to protect themselves so that the incidence of illnesses and injuries due to hazardous chemicals is reduced.

Working Safely with Chemicals Hazard recognition Risk Analysis Risk elimination/reduction General control Personal control

Working Safely with Chemicals List of chemicals Material Safety Data Sheet (MSDS) Labelling Training

Chemical Labelling Toxic Material Each container of hazardous chemical entering the workplace must be labeled or marked with: Identity of the chemical Appropriate hazard warnings Name of the responsible party

Chemical Labelling Labels should contain three types of hazard: Hazards related to pysico-chemical properties Hazards related to human health Hazards related to environment

Old and New Labeling System Old System New system (CLP / GHS)

Material Safety Data Sheets -MSDS Should include: Physical hazards, such as fire and explosion Health hazards, such as signs of exposure Routes of exposure Precautions for safe handling and use Emergency and first-aid procedures Control measures Must be readily accessible to employees in their work area

Regulation on the Health and Safety Precautions for working with chemicals (12.08.2013) Threshold Limit Values: (Mesleki Maruziyet Sınır Değerleri) TWA: Time weighted average (8 hr) STEL: Short term exposure limit (15 min)

Training Training is required for employees who are exposed to hazardous chemicals in their work area

Control Measures Replacement with less or non toxic one Isolation Ventilation (general/local) Engineering control Administrative control Personal protection equipment Health inspection

General/Local Ventilation Removes gaseous contaminants Should be designed properly

Safe Chemical Storage Dry Chemical Storage Keep organics and inorganics separated Liquid Chemical Storage According to the specifications given in MSDS forms hazardous chemicals should be stored saparately i.e. flammables separate from oxidizers, acids separate from bases Proper storage conditions must be provided

Safe Storage of Specific Chemicals Flammable Liquids Corrosive Materials Reactive (Oxidizers and Reducers) Cryogenics Gas Cylinders

Flammable Liquid Storage No smoking Use approved safety cans Store flammable liquids in an approved storage cabinet

Corrosive Material Storage DO NOT store acids and bases together Material should be stored in cabinets Store heavy containers on lower shelves Store on shelves with raised edges Do not store liquids above eye level

Reactive Chemicals Oxidizer: Chemicals that react with other substances; can result in fire or explosion Oxidizers supply oxygen to a fire Water-Reactive: Chemicals that react with water, water vapor or moist air Produces a flammable or toxic gas Sodium/phosphorus & aqueous material - fire Acid with cyanide compounds - toxic gas Chlorine & ammonia - toxic chloramines Pyrophoric: Chemicals that ignite on contact with air Flame may often be invisible

Reactive Chemical Storage Segregate: Acids from Bases Acids and bases from flammables Pyrophoric compounds from flammables Perchloric acid from reducing agents Water from water reactive chemicals Store thermally unstable materials in approved refrigerator

Cryogenic Chemicals Cold vapors (e.g. N2 at -196oC) can rapidly freeze human tissue Produces large volumes of gas that can displace breathable oxygen Materials can be embrittled Boiling/splashing occurs when filling a warm container Suitable personal protective equipment such as face shields, cryogenic gloves and long pants w/o cuffs should be used during transfer.

Personal Protective Equipment- PPE Good lab practices should be applied and suitable PPE should be used as necessary Mask Eye protection Nose-covered shoes, Lab coat, Long pants Gloves

Gas Cylinders Chain or strap cylinder to wall/bench Always use a cart & safety chain when transporting cylinder Store flammable gas bottles in flammable storage cabinet Keep non-compatible gases separate

First Aid and Safety Equipment Fire extiguisher Fist aid kit Emergency swover Eye wash station Spill kit Personal Protective Equipment