Welding Safety & Health. Understanding Weld Fume

Transcription

1 Welding Safety & Health Understanding Weld Fume

2 Disclaimer Every welding environment is unique with physical and health concerns and needs to be evaluated by a qualified Safety Professional or Certified Industrial Hygienist to determine the appropriate course of action for regulatory compliance and risk reduction in fume control. This presentation is intended for awareness and educational purposes of fume management methods and solutions only and should not be used to replace professional consultation or complete review of the owner s manual.

3 Weld Fume: Key Findings

4 Welding Fumes Overview Welding fumes consist of metallic oxides generated by the heating of the metal being welded, the welding consumables, or any coatings present on the base metal during arc or oxy-acetylene welding. Particle Size Up to 95% of weld fume is between micron 0.3 micron (μm) is most common size of weld fume particle

5 Potential Elements Aluminum: steel additive, electrode coatings Beryllium: hardening agent in copper, magnesium, aluminum alloys Cadmium: stainless steel, plated metals Copper: copper metals, electrodes Hexavalent Chromium: stainless steel, high alloy steels, electrodes, plated metals Iron Oxide: iron or steel processes Lead: solder, brass and bronze alloys, coating on steels Manganese: electrodes, high tensile steels Nickel: stainless steel, high alloy steels, electrodes, plated metals Zinc Oxide: galvanized, painted materials

6 Regulation/Enforcement Creates and enforces regulatory standards to ensure safe and healthful working conditions Regulations: PEL (Permissible Exposure Limits) The purpose of the Mine Safety and Health Administration is to prevent death, disease, and injury from mining and to promote safe and healthful workplaces for the Nation's miners.

7 Organizations Impacting Regulations American Conference of Governmental Industrial Hygienists Standards : TLV (Threshold Limit Values) National Institute for Occupational Safety and Health conducts scientific research, develops guidance and authoritative recommendations Standards: REL (Recommended Exposure Limits) The American Industrial Hygiene Association (AIHA) is a member-based association of occupational and environmental health and safety professionals.

8 Fume Regulations: OSHA & ACGIH Contaminant Prevalent In OSHA ACGIH Permissible Exposure Limit (PEL) Threshold Limit Values (TLV) Hexavalent Chromium Stainless, High Alloy Steels 5.0 micrograms, 5.0 µg/m 3 TWA 2.5 µg/m 3 TWA Action Level 0.05 milligrams, 0.05 mg/m 3 TWA Zinc (Zinc Oxide) Galvanized metal coatings 5.0 milligrams, 5.0 mg/m 3 TWA 2.0 milligrams, 2.0 mg/m 3 TWA Manganese Most welding fumes; electrodes & steels 5.0 milligrams Ceiling 0.02 milligram, 0.02 mg/m 3 TWA Aluminum Steel additive, electrode coatings 5.0 milligrams, 5.0 mg/m 3 TWA 1.0 milligram, 1.0 mg/m 3 TWA Nickel Stainless, Nickel Alloys 1.0 milligram, 1.0 mg/m 3 TWA 0.2 milligrams, 0.2 mg/m 3 TWA Iron (Iron Oxide) Most welding fumes 10.0 milligrams, 10.0 mg/m 3 TWA 5.0 milligrams, 5.0 mg/m 3 TWA Copper Copper metals, electrodes 0.1 milligrams, 0.1 mg/m 3 TWA 0.2 milligrams, 0.2 mg/m 3 TWA Cadmium Coatings of electrodes 0.1 milligrams, 0.1 mg/m 3 TWA 0.3 mg/m 3 Ceiling 0.1 milligrams, 0.1 mg/m 3 TWA 8

9 CHROME VI changes Cancer risk from Cr (VI) at new PEL is higher than asbestos and benzene risk at their PELs Asbestos: 6.7 deaths per 1000 workers Benzene: 10 deaths per 1000 workers Chrome VI: excess lung cancer deaths per 1000 workers for 45 years of exposure at new PEL of 5 ug/m 3

10 MANGANESE changes Most end users feel they are well below OSHA PEL s, but above the new ACGIH guidelines 0.1~0.5 Typical Heavy Equipment Manufacturing Weld Cell Respirable Mn in mg/m 3 (8-hr time-weighted average) Old ACGIH TLV Current NIOSH REL New ACGIH TLV (most Canadian provinces) Current OSHA Standard (Enforced - US)

11 Managing Weld Fume

12 Best Practice Plan Prevent Protect

13 Fume Identification Air Sampling

14 Process Modification/Substitution Modify Welding Process Process, Parameters Automation Change Materials Base Materials, Filler metals, Gases

15 Work Practice Controls Proper Training Follow proper weld procedures Eliminate overwelding Body & Equipment Positioning Keeping head out of the plume Position equipment arms Routine Preventive Maintenance

16 Engineering Controls Local Exhaust Ventilation/Source Capture Bernard Fume Guns Portable Industrial Systems Mobile and Stationary (Wall or Column Mounted) Systems Extended Source Capture

17 Filtair Capture 5 ZoneFlow Technology Value Proposition: Improve welder efficiency via largest capture area and reduced welder interaction Increased welder protection from a greater distance

18 ZoneFlow Technology

19 Personal Protective Equipment - Respirators Air Purifying Disposable, Half Mask and Powered Air Purifying Respirators Atmosphere Supplying Supplied Air Respirators

20 Miller Weld Fume Respirators N95 Disposable Respirators LPR-100 Half Mask Respirators Powered Air-Purifying Respirators (PAPR)

21 Respirators Required Must establish a program (ANSI Z ) Selection Training Use and limitations Cleaning and maintenance Fit Test MSHA does not accept respiratory protection in lieu of feasible engineering controls

22 Choosing the Right Respirator Calculate Maximum Use Concentration (MUC) Find the MSHA TLV for a given substance Multiply TLV by APF of respirator Example: PAPR with loose fitting head seal is APF mg/m³ * APF 25 = 1.25 mg/m³ (MUC) Example Facility: Hexavalent Chromium sample result of 1 mg/m³ MUC of PAPR with Hexavalent Chromium: 6.25 mg/m³ MUC of Half Mask with Hexavalent Chromium: 0.5 mg/m³ In this example, a PAPR would provide adequate protection.

23 Respirator Filters HEPA Filters: at least 99.97% efficient in removing monodisperse particles of 0.3 micrometers in diameter. Used with PAPR systems N, R, or P Filters: Indicate resistance to oil 95%, 99% and 100% Efficiencies Used with Non-Powered Particulate Respirators

24 ITW s Weld Fume Portfolio

25 Questions? Thank You!