Welding

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Welding
Fumes
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Welding Fumes

• What Are Welding Fumes ?
• Health Hazards
• MSHA Regulations
• Sampling Methods
• Controls

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Welding Fumes

• What Are Welding Fumes ?
• Health Hazards
• MSHA Regulations
• Sampling Methods
• Controls

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What Are Welding Fumes ?

• Welding Causes Solid Metal To Vaporize
• As Vaporized Metal Cools, It Condenses To Reform
  As Solid Particles - FUME
• Fumes Are Very Small Particles - - Usually Much
  Smaller Than Dust
• Dust Usually Larger Than 1 Micron
• Fumes Can Be As Small As 1/1,000 Micron
• Unless Captured And Removed, Fumes Remain
  Suspended In Air Indefinitely

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Composition of Welding Fumes

• Composition Varies Depending On
• Material Being Welded
• Welding Process, Rod, Electrode Type
• Coatings On Material, Rod, Electrode
• Typical Welding Fume Constituents
• Aluminum, Cadmium, Chromium, Iron, Moly
• Cobalt, Copper, Zinc, Manganese, Tin, Lead
• Nickel, Arsenic, Mercury, Vanadium,
• Beryllium, Magnesium, Titanium,
• May Be Metal or Oxide

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Welding Fumes

• What Are Welding Fumes ?
• Health Hazards
• MSHA Regulations
• Sampling Methods
• Controls

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Exposure Primarily By Inhalation

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Exposure Primarily By Inhalation Fumes Are 100
Respirable

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Exposure Primarily By Inhalation Fumes Are 100
Respirable What Does Respirable Mean ?

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Exposure Primarily By Inhalation Fumes Are 100
Respirable What Does Respirable Mean ?

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How Do You Know What You Are Being Exposed To ?
Hazards ?

• Supplier Or Equipment Manufacturer
• Material Safety Data Sheet (MSDS)
• Assume Paint Contains Lead
• Assume Corrosion Resistant Coatings Contain Zinc
  Or Cadmium
• Assume Wear Materials Contain Manganese
• Assume High Strength Steel Contains Chrome,
  Manganese, Moly, Nickel

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Welding Fume Toxicity

• Kidney Nervous Liver GI
  Lung
• Aluminum X
  X
• Beryllium
  X
• Cadmium X X
  X X
• Chromium X X X
  X
• Cobalt X
  X X
• Copper
  X X
• Iron X
  X X X
• Lead X X
  X
• Manganese X
  X
• Nickel X
  X
• Zinc
  X X

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Welding Fume Toxicity

• Acute Toxicity
• Exposure To High Concentration Over Relatively
  Short Time
• Symptoms Appear Relatively Quickly After Exposure
  
• Chronic Toxicity
• Exposure To Lower Concentration Over Long Time
  (Months, Years)
• Symptoms Appear Long After Initial Exposure

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Welding Fume Toxicity

• Exposure Usually Involves More Than One Metal
• Toxic Effects May Be Additive
• Examples
• Blood - Manganese and Lead
• CNS - Manganese and Lead
• Kidney - Lead and Cadmium
• Respiratory System - Magnesium, Manganese,
  Copper, and Zinc

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Welding Fume Toxicity

• Metal Fume Fever
• Symptoms Are Fever, Chills, Shaking
• Symptoms Appear 4-12 Hrs After Exp.
• Recovery Usually Within 1 Day
• Usually Associated With Brief High Inhalation
  Exposure To Zinc, But Magnesium Copper Also May
  Cause
• Daily Exposure May Confer Immunity
• Symptoms May Return If Exposure Interrupted
  (3-Day Weekend)

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Welding Fume Toxicity

• Welding Fumes Can Cause Cancer
• Arsenic (Lung, Lymphatic)
• Beryllium (Lung)
• Cadmium (Prostatic and Lung)
• Chromium (Lung)
• Nickel (Lung)
• Welders May Also Be Exposed To
• Silica, Asbestos, Ozone
• Thermal Decomposition of Paint, Flux, Electrode
  Coatings (CO, CO2, NO, NO2, HCN, COCl2, Fluoride
  Gases, Smoke, Etc.)

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Welding Fumes

• What Are Welding Fumes ?
• Health Hazards
• MSHA Regulations
• Sampling Methods
• Controls

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MSHA Regulations

• 56/57.5001 Exposure Limits
• 56/57.5002 Monitoring
• 56/57.5005 Controls
• 56/57.14213(b) Ventilation
• 56/57.20011 Barricades, Warnings
• Part 46 and Part 48 Training

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MSHA Regulations

• 56/57.5001 Establishes Exposure Limits For
  Airborne Contaminants
• TWA8 And Ceiling Limits Listed In 1973 ACGIH
  Booklet of Threshold Limit Values (TLVs)
• TWA8 Time Weighted Average For 8 Hrs
• Ceiling Limits Cannot Be Exceeded For Any Length
  Of Time
• ACGIH 1973 TLV Booklet References 1968 PA Rules
  For Short Term Limits

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MSHA Regulations

• 56/57.5002 Dust, Gas, Mist, And Fume Surveys
  Shall Be Conducted As Frequently As Necessary To
  Determine The Adequacy Of Control Measures
• 56/57.5005 Control of Harmful Airborne
  Contaminants Shall Be, Insofar As Feasible, By
  Engineering Controls
• Respirators Permitted Under Certain Circumstances

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MSHA Regulations

• 56/57.14213(b) All Welding Operations Shall Be
  Well Ventilated
• 56/57.20011 Areas Where Health or Safety
  Hazards Exist That Are Not Immediately Obvious
  Shall Be Barricaded Or Warning Signs
  Posted
• Part 46 and Part 48 Training

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Welding Fumes

• What Are Welding Fumes ?
• Health Hazards
• MSHA Regulations
• Sampling Methods
• Controls

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Sampling Methods

• For Compliance With 56/57.5001 And 56/57.5002
• Full Shift Or Short Term

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Sampling Methods

• For Compliance With 56/57.5001 And 56/57.5002
• Full Shift Or Short Term
• Sample Pump, Pump Calibrator, Filters

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Sampling Methods

• For Compliance With 56/57.5001 And 56/57.5002
• Full Shift Or Short Term
• Sample Pump, Pump Calibrator, Filters
  
• Place Filter In Breathing Zone Under Hood

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Sampling Methods

• For Compliance With 56/57.5001 And 56/57.5002
• Full Shift Or Short Term
• Sample Pump, Pump Calibrator, Filters
  
• Place Filter In Breathing Zone Under Hood
• Pump Draws Air Over Filter Contaminants Captured
  On Filter

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Sampling Methods

• Analytic Lab Determines Weights Of Individual
  Contaminants On Filter
• Weights Converted To Concentrations

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Sampling Methods

• Analytic Lab Determines Weights Of Individual
  Contaminants On Filter
• Weights Converted To Concentrations
• Measured Concentration Compared To Established
  Exposure Limit
• Measured Less Than Limit - - No Action Reqd
• Measured Over Limit - - Implement Controls

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Welding Fumes

• What Are Welding Fumes ?
• Health Hazards
• MSHA Regulations
• Sampling Methods
• Controls

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Controls (56/57.5005)

• Feasible Engineering Controls
• Personal Protective Equipment (PPE)
• PPE Allowed As Means Of Compliance Only In
  Limited Situations
• Where Feasible Engineering Controls Do Not Exist
• While Installing Engr. Controls
• Occasional Entry Into Hazardous Atmosphere For
  Maintenance

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Engineering Controls

• General Ventilation
• Natural or Mechanically Induced (Fans) Airflow
  pushed Or Pulled Over Work Area That Dilutes and
  Carries Away Contaminants

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General Ventilation

• Outdoors - Wind
• Indoors
• Open Shop Doors/Windows
• Fans Fixed - Roof, Walls, Windows
• Fans Portable
• Blow Fresh Air Into Work Area, But Dont Blow
  Fumes Into Welders Breathing Zone
• Need Provision For Make Up Air

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Engineering Controls

• Local Exhaust Ventilation
• Captures and Removes Airborne Contaminants Before
  They Escape Into Workplace Air
• Local Exhaust Always Preferred For Toxic Airborne
  Contaminants

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Local Exhaust Ventilation

• Capture Hood Fixed Duct System

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Local Exhaust Ventilation

• Portable Fume Eliminator

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Local Exhaust Ventilation

• Down Draft Table

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1350 fpm
100 fpm
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Respiratory Protection

• Air Purifying Or Supplied Air
• May Be Integral With Welding Hood
• NIOSH Part 84 Approved For Fumes

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Welders Powered Air Purifying Respirator (PAPR)
Half-Mask Cartridge Respirator
Supplied-Air Respirator
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Respiratory Protection

• Air Purifying Or Supplied Air
• May Be Integral With Welding Hood
• NIOSH Part 84 Approved For Fumes
• Respirator Use Must Include Implementation of
  Respiratory Protection Program (See ANSI
  Z88.2-1969)
• Written Procedures on Selection and Use
• Respirator Training and Fit Testing
• Respirator Inspection, Cleaning, Storage
• Workplace Surveillance
• Medical Evaluation Recommended

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Thank You