Glass IndustryGlass Industry

GLASS, CERAMICS AND GLASS, CERAMICS AND RELATED MATERIALSRELATED MATERIALS          

glass glass

synthetic vitreous fibres synthetic vitreous fibres

pottery pottery

ceramic tile ceramic tile

industrial ceramicsindustrial ceramics

brick and tile brick and tile

refractories refractories

synthetic gems synthetic gems

optical fibres.optical fibres.

Common Processes and Common Processes and HazardsHazards

Batch raw material processesBatch raw material processes Firing or melting processesFiring or melting processes Material handling in production, Material handling in production,

fabrication, packaging and fabrication, packaging and warehousingwarehousing

Rebuilds and reconstruction Rebuilds and reconstruction activitiesactivities

DefinitionDefinition

an inorganic product of fusion that has an inorganic product of fusion that has cooled to a rigid condition without cooled to a rigid condition without crystallizing crystallizing

When glass is cooled from the hot molten When glass is cooled from the hot molten state, it gradually increases in viscosity state, it gradually increases in viscosity without crystallization over a wide without crystallization over a wide temperature range, until it assumes its temperature range, until it assumes its characteristic hard, brittle form. Cooling characteristic hard, brittle form. Cooling is controlled to prevent crystallization, or is controlled to prevent crystallization, or high strain.high strain.

Glass, chemically, is actually more like Glass, chemically, is actually more like a liquid, but at room temperature it is a liquid, but at room temperature it is so viscous or 'sticky' it looks and feels so viscous or 'sticky' it looks and feels like a solid. At higher temperatures like a solid. At higher temperatures glass gradually becomes softer and glass gradually becomes softer and more like a liquid. It is this latter more like a liquid. It is this latter property which allows glass to be property which allows glass to be poured, blown, pressed and moulded poured, blown, pressed and moulded into such a variety of shapes.into such a variety of shapes.

HistoryHistory Glass technology has evolved for 6,000 yearsGlass technology has evolved for 6,000 years A most important development in glass A most important development in glass

technology was the use of a blow pipe technology was the use of a blow pipe The first glass was coloured because of the The first glass was coloured because of the

presence of various impurities such as oxides presence of various impurities such as oxides of iron and chromium. Virtually colourless of iron and chromium. Virtually colourless glass was first made some 1,500 years ago.glass was first made some 1,500 years ago.

Today many products of glass are made in Today many products of glass are made in fully automatic processing lines fully automatic processing lines

Although glass is one of the oldest materials, Although glass is one of the oldest materials, its properties are unique and not yet fully its properties are unique and not yet fully understood.understood.

ApplicationsApplications

ChemistryChemistry PharmacyPharmacy Electrical and electronics industries Electrical and electronics industries Optics industriesOptics industries Construction and lighting industriesConstruction and lighting industries

Major constituentsMajor constituents Silica sandSilica sand Soda ashSoda ash Lime stoneLime stone DolomiteDolomite Feldspathic materials Feldspathic materials Lead oxideLead oxide Boric acidBoric acid Crushed glassCrushed glass

Minor constituentsMinor constituents

The remainder of the batch consists of The remainder of the batch consists of several additional ingredients, chosen several additional ingredients, chosen from a group of some 15 to 20 materials from a group of some 15 to 20 materials commonly referred to as minor commonly referred to as minor ingredients. ingredients.

These latter additions are added with a These latter additions are added with a view to providing some specific function view to providing some specific function or quality, such as colour, which is to be or quality, such as colour, which is to be realized during the glass preparation realized during the glass preparation process.process.

Common glassesCommon glasses

Soda-lime-silica glass (commercial Soda-lime-silica glass (commercial glass)glass)

Lead-potash-silica glassLead-potash-silica glass Borosilicate glassBorosilicate glass

Soda-lime-silica glassSoda-lime-silica glass

SiO2 (silica) 70%SiO2 (silica) 70% Na2O (sodium oxide)12% Na2O (sodium oxide)12% CaO (calcium oxide) 8% CaO (calcium oxide) 8% MgO (magnesium oxide) 3% MgO (magnesium oxide) 3% Al2O3 (aluminium oxide) Al2O3 (aluminium oxide) 1%1%

Commercial glass is Commercial glass is colourlesscolourless

Additional chemicals have to be added Additional chemicals have to be added to produce different colours of glass to produce different colours of glass such as green, blue or brown glass. such as green, blue or brown glass.

Lead-potash-silica glassLead-potash-silica glass It is made by using lead oxide It is made by using lead oxide

instead of calcium oxide, and instead of calcium oxide, and potassium oxide instead of all potassium oxide instead of all or most of the sodium oxide or most of the sodium oxide

High refractive index High refractive index Relatively soft surfaceRelatively soft surface High electrical resistivity High electrical resistivity Radiation protection (hRadiation protection (higher igher

lead oxide contents typically lead oxide contents typically 65%absorb gamma rays and other 65%absorb gamma rays and other forms of harmful radiation) forms of harmful radiation)

Borosilicate glassBorosilicate glass

silica (70-80%) and silica (70-80%) and boric oxide (7-13%) boric oxide (7-13%) with smaller with smaller amounts of the amounts of the alkalis (sodium and alkalis (sodium and potassium oxides) potassium oxides) and aluminium and aluminium oxide. oxide.

ovenware and other ovenware and other heat-resisting ware heat-resisting ware (Pyrex)(Pyrex)

Types of special glass Types of special glass include :include :

Vitreous silicaVitreous silica Aluminosilicate glass Aluminosilicate glass Alkali-barium silicate glassAlkali-barium silicate glass Technical glass Technical glass Glass ceramics Glass ceramics Opical glass Opical glass Sealing glass Sealing glass

Glass makingGlass making

Pot processPot process Tank processTank process

Pot ProcessPot Process

The manufactured of high quality glass The manufactured of high quality glass such as optical and mirror glass & such as optical and mirror glass & small quantities of specialty glasssmall quantities of specialty glass

Hazard of hand shoveling & filling of Hazard of hand shoveling & filling of the potsthe pots

Optical and specialty glasses contain Optical and specialty glasses contain heavy metals (lead, barium and heavy metals (lead, barium and manganese)manganese)

Pot FurnacePot Furnace

Tank ProcessTank Process

Permits enclosed &continuous feeding Permits enclosed &continuous feeding of bath ingredient (reduced dust of bath ingredient (reduced dust exposure)exposure)

Refractory blocks and bricks used in Refractory blocks and bricks used in the construction of the furnaces and the construction of the furnaces and tanks contain free silica.tanks contain free silica.

Tank FurnaceTank Furnace

Glass objects formed by:Glass objects formed by:

BlowingBlowing PressingPressing CastingCasting RollingRolling DrawingDrawing FloatingFloating

The blow pipeThe blow pipe

Pressing & Blowing Pressing & Blowing

Continuous float processContinuous float process

  Ribbon of float glass exiting from Ribbon of float glass exiting from lehr after being annealedlehr after being annealed

Glass additiveGlass additive

Accelerate meltingAccelerate melting StabilizerStabilizer Improved optical propertiesImproved optical properties Remove bubblesRemove bubbles ColorColor

Accelerate melting Accelerate melting

FluorineFluorine Calcium fluorideCalcium fluoride Sodium silicafluorideSodium silicafluoride

StabilizersStabilizers

Increased resistanceIncreased resistance Barium , Lead , Ca , Mg ,Zn oxidesBarium , Lead , Ca , Mg ,Zn oxides

Improved optical Improved optical propertiesproperties

Rare earth metalsRare earth metals ThoriumThorium

Remove bubblesRemove bubbles

Salts of arsenicSalts of arsenic

antimonyantimony

ColorColor

Salts of chromium ( green –yellow)Salts of chromium ( green –yellow)

cobalt (red – blue )cobalt (red – blue )

cadmium (yellow)cadmium (yellow)

manganese manganese

nickel (black)nickel (black)

selenium ( red)selenium ( red)

Potential health and Potential health and safety hazards found safety hazards found

during during manufacturing of manufacturing of glass, ceramic and glass, ceramic and related materialsrelated materials

Ergonomic stressors; Ergonomic stressors; biomechanical hazards biomechanical hazards

Uses or sources of Uses or sources of exposureexposureto hazard to hazard

Potential effects Potential effects (physical hazards(physical hazardsor health effects) or health effects)

Precautions or Precautions or control strategies control strategies

Overexertion Overexertion from manual from manual material-material-handling handling practices , poor practices , poor posture, high posture, high frequency/duratifrequency/duration of tasks on of tasks involving lifting, involving lifting, pushing or pushing or pulling pulling

Strains and Strains and sprains in sprains in skeletal muscular skeletal muscular damage to back, damage to back, upper and lower upper and lower extremitiesextremitiesExcessive Excessive physical and physical and mental fatigue mental fatigue can cause errors can cause errors leading to leading to secondary secondary incidents incidents

· Physical · Physical demands demands assessments of assessments of suspect job taskssuspect job tasks

· Use of material-· Use of material-handling devices handling devices including lift including lift assists, powered assists, powered vehiclesvehicles· Process · Process automation or automation or semi automationsemi automation· Education on · Education on proper techniques proper techniques

  Vacuum lift assist being used to Vacuum lift assist being used to handle 20 to 30 kg packages of handle 20 to 30 kg packages of

textile glasstextile glass..

Physical hazardsPhysical hazardsUses or sources Uses or sources of exposureof exposureto hazardto hazard

Potential effects Potential effects (physical hazards(physical hazardsor health effects)or health effects)

Precautions or Precautions or control strategiescontrol strategies

Caught in or Caught in or struck by or struck by or against fixed or against fixed or mobile mobile equipmentequipmentSlips, trips and Slips, trips and falls on walking falls on walking and working and working surfaces, hoses surfaces, hoses and other and other equipment, equipment, tools or tools or materials materials

Abrasions, cuts, Abrasions, cuts, contusions, contusions, lacerations,lacerations,punctures, punctures, fractures, fractures, amputations amputations

· Safe work · Safe work proceduresprocedures· Good · Good housekeeping housekeeping practicepractice· Equipment design · Equipment design and layoutand layout· Job design and · Job design and structurestructure· Anti-slip surfaces · Anti-slip surfaces

Walking and working surfaces Walking and working surfaces should be free from trip and should be free from trip and

slip hazardsslip hazards

Robotics used in plate-glass Robotics used in plate-glass handling reduces ergonomic and handling reduces ergonomic and

laceration hazardslaceration hazards

  Machine guarding protects Machine guarding protects operators from rotating shafts, operators from rotating shafts,

belts or drive chainsbelts or drive chains

NoiseNoiseUses or sources of Uses or sources of exposureexposureto hazardto hazard

Potential Potential effects effects (physical (physical hazardshazardsor health or health effects)effects)

Precautions or control Precautions or control strategiesstrategies

Pneumatic Pneumatic vibrators, vibrators, compressors, compressors, mixing drive mixing drive motors, blowers motors, blowers and dust and dust collectors, collectors, conveyors, conveyors, packaging packaging equipment, etc.equipment, etc.

Occupational Occupational hearing loss, hearing loss, communication communication difficulty and difficulty and stress stress

· Isolation, · Isolation, enclosure, reflective enclosure, reflective barriers or sound barriers or sound absorption materialsabsorption materials· Innovative design · Innovative design of machine guarding of machine guarding

· Specifying lower-· Specifying lower-noise motors or noise motors or equipmentequipment· Use of hearing · Use of hearing protection and a protection and a hearing conservation hearing conservation programmerprogrammer

Radiant heat, high-temperature Radiant heat, high-temperature work environmentwork environment

Uses or sources Uses or sources of exposureof exposureto hazardto hazard

Potential Potential effects effects (physical (physical hazardshazardsor health or health effects)effects)

Precautions or control Precautions or control strategiesstrategies

Heating or Heating or melting melting processes processes during during maintenance or maintenance or emergency emergency response response activitiesactivities

Heat Heat stressstressor or thermal thermal burns ,burns ,

heat heat cataracts cataracts

· Shielding ,barriers, · Shielding ,barriers, reflective surfaces, reflective surfaces, insulationinsulation· Water-cooled · Water-cooled equipment equipment · Air-conditioned control · Air-conditioned control rooms rooms

· Heat-protective · Heat-protective clothing and glovesclothing and gloves

· Acclimatization to hot · Acclimatization to hot working environments, working environments, intake of water and intake of water and electrolyte beverages, electrolyte beverages, controlled work-rest controlled work-rest regimensregimens

  Quality-control technician taking glass samples from Quality-control technician taking glass samples from furnace and  wearing personal heat protective equipment furnace and  wearing personal heat protective equipment

and IR shielding glassesand IR shielding glasses

Inhalation of airborne from raw materialInhalation of airborne from raw material(crystalline silica, clay, lime, iron oxide, (crystalline silica, clay, lime, iron oxide,

nuisance dusts )nuisance dusts )Uses or sources of Uses or sources of exposure to hazardexposure to hazard

Potential effects Potential effects (physical hazards(physical hazardsor health effects)or health effects)

Precautions or control Precautions or control strategiesstrategies

Handling, Handling, Exposures during Exposures during routine routine maintenance maintenance activities, rebuildsactivities, rebuilds

non-ventilated non-ventilated equipment or equipment or mixing equipmentmixing equipmentRaw materials are Raw materials are extremely extremely

abrasive, causing abrasive, causing deterioration of deterioration of transfer or storage transfer or storage system in system in manufacturing manufacturing processes processes

Range from Range from irritation to irritation to chemical chemical burns to burns to chronic chronic effects such effects such as decreased as decreased pulmonary pulmonary function, function, lung disease, lung disease, pneumoconiopneumoconiosis silicosissis silicosis

·Equipment exhaust ·Equipment exhaust ventilation ventilation

· Proper material · Proper material handlinghandling

· Isolation of operators · Isolation of operators

·PPE·PPE

· Active leak detection · Active leak detection and repairs and repairs

. Periodic medical . Periodic medical screening, surveillance screening, surveillance and early intervention and early intervention based on exposure based on exposure

Heavy metals particulates or fumes (lead, Heavy metals particulates or fumes (lead, cadmium, chromium, arsenic, copper, nickel, cadmium, chromium, arsenic, copper, nickel,

cobalt, manganese or tin)cobalt, manganese or tin) Uses or sources of Uses or sources of exposureexposureto hazardto hazard

Potential Potential effects effects (physical (physical hazard or hazard or health health effect)effect)

Precautions or control Precautions or control strategiesstrategies

As raw materials or As raw materials or impurities in glazes, impurities in glazes, coloring agentscoloring agentsMaintenance and Maintenance and construction activities construction activities involving soldering, involving soldering, cutting, welding cutting, welding Grinding, cutting, Grinding, cutting, drilling structural drilling structural members or machinery members or machinery

Heavy Heavy metal metal toxicittoxicity y

· · Engineering controlsEngineering controls

· HEPA-ventilated · HEPA-ventilated portable power toolsportable power tools· Use of ventilated booths · Use of ventilated booths for spray painting & for spray painting & coating activities coating activities · Good work practices to · Good work practices to reduce airborne reduce airborne particulates( wet method)particulates( wet method)· Personal hygiene, · Personal hygiene, segregated laundering of segregated laundering of contaminated work contaminated work clothesclothes· Respiratory protection · Respiratory protection and protective clothingand protective clothing· Medical surveillance and · Medical surveillance and biological monitoring biological monitoring

Bases (sodium hydroxide) or Bases (sodium hydroxide) or acids (HCL, sulphuric acid, HF)acids (HCL, sulphuric acid, HF)

Uses or sources Uses or sources of exposureof exposureto hazardto hazard

Potential effectsPotential effects

(physical hazards or health (physical hazards or health effects)effects)

Precautions or Precautions or control strategiescontrol strategies

wastewater wastewater treatment and treatment and pH controlpH controlAcid cleaning Acid cleaning or etching or etching processes processes with HF with HF

.Corrosive to skin .Corrosive to skin or eyesor eyesRespiratory tract Respiratory tract and mucous and mucous membrane irritantmembrane irritant.HF causes severe .HF causes severe skin burns that skin burns that can go undetected can go undetected for hours for hours

· Process isolation· Process isolation· Safe handling · Safe handling practicespractices· PPE use-· PPE use-respiratory respiratory protection, rubber protection, rubber gloves, faceshield gloves, faceshield with eye with eye protection, protection, eyewash/safety eyewash/safety showershower· Exhaust · Exhaust ventilation to ventilation to control acid control acid vapours or vapours or aerosols aerosols

Propane, natural gas, gasoline, Propane, natural gas, gasoline, fuel oilfuel oil

Uses or Uses or sources of sources of exposureexposureto hazardto hazard

Potential effects Potential effects (physical (physical hazards or hazards or health effects)health effects)

Precautions or control Precautions or control strategiesstrategies

Fuels for Fuels for process process heat & heat & powered powered industrial industrial trucks trucks

Fire and Fire and explosion explosion hazards,hazards,Exposure Exposure to CO or to CO or other other products products of of incompletincomplete e combustiocombustion n

· · Proper design and Proper design and inspections of storage and inspections of storage and distribution system, and distribution system, and combustion process combustion process controlscontrols· Safe unloading, filling and · Safe unloading, filling and handling practicehandling practice· Routine testing and · Routine testing and control of combustion control of combustion processes processes

Inhalation of bioaerosolsInhalation of bioaerosolsUses or sources of Uses or sources of exposureexposureto hazardto hazard

Potential effects Potential effects (physical hazards (physical hazards or health effects)or health effects)

Precautions or control Precautions or control strategiesstrategies

Aerosol Aerosol containing containing bacteria, moulds bacteria, moulds or fungus or fungus generated from generated from spraying process spraying process or cooling water or cooling water in humidification in humidification processes, processes, ventilation ventilation systemssystems

.Waterborne .Waterborne illness with illness with systemic systemic non specific non specific flu-like flu-like symptoms, .fsymptoms, .fatigueatigue.Potential .Potential for for dermatitis dermatitis

· Process design and · Process design and mist reductionmist reduction· Process and · Process and cooling water cooling water treatment with treatment with biocidesbiocides· Routine cleaning · Routine cleaning and sanitizationand sanitization· Elimination · Elimination nutrient source in nutrient source in water systemwater system· Respiratory · Respiratory protectionprotection· PPE, gloves and · PPE, gloves and good personal good personal hygiene hygiene

Aerosols of reused waste water Aerosols of reused waste water that is not treated can cause that is not treated can cause

waterborne illnesswaterborne illness

Demographics of injuries Demographics of injuries and illness cases and illness cases

  Nature of occupational injuries Nature of occupational injuries and illnesses lost workday cases and illnesses lost workday cases

19941994

  Nature of occupational injuries Nature of occupational injuries and illnesses lost workday and illnesses lost workday

cases1994cases1994

Body part affected in lost workday Body part affected in lost workday injury or illness cases1994injury or illness cases1994

RefrencesRefrences

Recognition of Health Hazard in Recognition of Health Hazard in Industry; William A.BurgessIndustry; William A.Burgess

Glass, Ceramics and Related Glass, Ceramics and Related Materials; Materials; Jonathan P.HellersteinJonathan P.Hellerstein

Technical Approach to Technical Approach to Glass ;M.B.Volf     Glass ;M.B.Volf    

Sources of occupational Sources of occupational injuries and illnesses lost injuries and illnesses lost

workday casesworkday cases