1. This Presentation is provided to you by: WPSAmerica.com Industry Standard Welding Procedures Software for AWS and ASME Codes

2. Welding fume Management

3. In what units is fume generation measured? What units apply to particulate TLV’s? A FCAW welder produces how much fumes per year?

4. Fume emission level versus shielding atmosphere 100 0 0 20 0 80 10 5 85 5 5 90 0 8 92 0 1,5 98,5 200 400 600 800 1.000 740 470 350 290 190 150 Fumes (mg/min.) CO2 O2 Ar Wire ER 70S3 dia.: 1,2mm 280 - 300 A 28 - 30 V

5. Ar + 18% CO2 Ar + 13% CO2 + 5% He Ar + 10% CO2 Ar + 6% CO2 + 2% O2 Ar + 5% CO2 + 4,5% O2 Ar + 3,5% O2 Influence of CO2 content in the shielding gas on CO emissions 0 50 100 150 200 160 130 120 80 40 0 CO content (ppm) Ar + 3,5% O2 Wire ER 70S3 1,2mm Wire = 10 m/min I = 280 / 300 A U= 32 / 34 V I

7. Airborne particulates Typical size range Atmospheric dust Very fine (10E-8 cm) Fine (10E-4 cm) Coarse (1 cm ) Welding fume and dust Tobacco smoke Coal dust Cement dust Respirable particles

8. Factors affecting fume generation rate t Type of shielding gas if applicable to the process t Welding current t Welding voltage t Arc length t Polarity t Current density t Humidity t Base plate t Electrode angle t Electrode type t Formulation of the electrode and wire

9. Fume emission testing device Filters weighed before and after test Welding time known 30 seconds/1 min exhaust fume emission rate calculated: average of five readings measurements in mg/minute Air exhaust fan Filters Conical column Rotating table FCAW gun mount Observation window AWS F 1.2-92( Laboratory method for measuring fume generation rates and total fume emission for Welding and Allied Processes) 20mm plate, 20 inch dia, 4 inch efffective, 120 lbs.

10. Typical fume generation Rates ProcessRange g/min SMAW0.2 - 1.2 FCAW0.5 - 3.5 GMAW0.1 - 0.5 GMAW(AL)0.1 - 1.5

11. The filter is about the size of a medium PIZZA! Clean and used filter, after 30 seconds!

12. Welding fumes composition

14. Potential Health Effects

15. Hexavalent Chromium t Hexavalent chromium is a known lung carcinogen t SMAW stainless steel electrodes produce high level of Cr VI ( 50% - 70% of total chromium) t Lithium compounds reduce Cr VI significantly t FCAW stainless steel electrodes produce high level of Cr VI ( 30% - 60% of total Chromium) t GMAW of stainless steel produces very little Cr VI ( < 10% of total Chromium) t ANSI/AWS F3.1 - 89 : Guide for Welding Fume Control

19. Welding fumes Welding amperage fume generation g/min ?

20. Influence of the shielding gas and parameter set up on fume emission level in GMAW Influence of the shielding gas and parameter set up on fume emission level in GMAW (Wire: ER 70S3) Ar + 3% CO2 + 1% O2 Ar + 10% CO2Ar + 18% CO2 Tension (V) 152025303540 0 200 400 600 800 1.000 170 A Fumes (mg/min) 300 A 350 A 100 A

21. 3-D representation of fume generation for non pulsed GMAW For a given wire feed speed or amperage: –Low fume generation in short circuit range –As voltage is increased, transfer transits through globular range causing a first maxima –Fine tuning of spray transfer gives a minima –As voltage increased beyond the optimum, fume generation rate increases

22. Fume Concentration Fume concentration is measured in Milligrams per cubic meter (mg/m3)

23. Some terms used in the welding fume legislation OSHA: Occupational Health and Safety Administration PEL: Permissible Exposure Limit (8 hours) TWA: Time weighted average (8 hour exposure) NIOSH: National Institute of Occupational Safety and Health ACGIH: American Conference of Governmental Industrial Hygienists OEL: Occupational Exposure Limits (8 hours) TLV: Thresh hold Limit Value (8 hours) TWAEV: Time Weighted Average Exposure Value (8 hours) STEL: Short Term Exposure Limit ( TLV-STEL : 15 minutes) C: Ceiling value ( TLV-C : instanteneous max value not to be exceeded) General ventilation must move 2,000 cu feet per minute Each welder should have 10,000 cu feet of barrier free work space Serious violation : $ 7,000 per violation Repeat violation: $ 70,000 per violation

25. Air Sampling Meter

26. Daily variation of Fume Concentration 08:00 12:00 16:00 Fume concentration mg/m3 Exposure limit Time weighted Average Actual Exposure

27. Fume generation rates FCAW & SMAW

28. GMAW values Typical fume generation rates at 260 amps

29. MCAW values Typical fume generation rates at 260 amps

30. FCAW values Typical fume generation rates at 260 amps

31. Fume weight per welder per year ? Fume generation rate of 1g/minute 2000 hours/yr at 20% duty cycle = 400 hours welding time 400 hours X 1 g/minute X 60 = 24,000 grams = 52.8 pounds Equal to the weight of one coil of wire per year!

32. NOTE: 200,000 hours of arc time at 18% duty cycle translates to approximately 556 welders. FUME GENERATION – 1.6 mm FCAW : 200,000 HOURS OF ARC TIME NOTE: 200,000 hours of arc time at 18% duty cycle translates to approximately 556 welders.

33. Through choice of gas and wire fumes reduced Annually by 4.75 MT!!

34. Influence of pulsed current on fume emission level ER 70S3 1,2mm / ARCAL14 100170240300350 0 200 400 600 800 Amperage (A) Fumes (mg/min) Arcal 14 Arcal 14 pulsed

35. FUME EMISSION LEVEL Parameter set up : I = 250 A U = 26 V 0 0,2 0,4 0,6 0,8 1 1,2 Fume emission level (g/min) SD206 ATAL 5 SD207 ARCAL 22 1,05 0,52 Metal Cored Wire Rutile FCW for all positions GREEN 101 ARCAL 22 0 0,2 0,4 0,6 0,8 1 1,2 0,57 0,37 SD100 ATAL 5 Fume emission level (g/min)

36. Source capture

37. Applications?

38. Source capture?

39. Fume extracting gun

40. Test results of air quality Sample LocationSampling time in minutes Volume sampled in liters Lab results (micro grams per sample) Concentration (mg/m 3 ) 99V001Welder under general exhaust fume hood, fume hood switched OFF 61122.1342428.0 99V002Welder under general exhaust, fume hood switched ON 61122.1196916.1 99V003Welder under fume hood, with a smoke extracting gun 62122.41711.38 Ontario Ministry of Labour, TWAEV for welding fumes5.00

41. Welding Fume management Questions?