1 / 33

Engineering Controls for Silica

Engineering Controls for Silica. Art Wickman, CIH Georgia Tech Safety & Health Consultation Program. Control Options. 1. Wet Methods 2. Ventilated Tools 3. Abrasive Blasting Controls: Alternate Media Alternate Methods. Engineering Controls: 1. Wet Methods. Water suppression of dust

liberty
Télécharger la présentation

Engineering Controls for Silica

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Engineering Controls for Silica • Art Wickman, CIH • Georgia Tech Safety & Health Consultation Program

  2. Control Options • 1. Wet Methods • 2. Ventilated Tools • 3. Abrasive Blasting Controls: • Alternate Media • Alternate Methods

  3. Engineering Controls:1. Wet Methods • Water suppression of dust • Very effective method • Requires planning for supply of water and clean up

  4. Note: Safety Glasses Required

  5. Wet Methods: Portable Saw

  6. Block Cutting: Dry Monitoring Data: • 8 X OSHA PEL • Time Weighted Average (TWA)

  7. Block Cutting--Dry

  8. Wet Methods: Block Cutting

  9. Wet Methods: Requires Pre-planning

  10. Wet Methods: Joint Cutting

  11. Wet Methods: Jack hammer, chipping hammer, etc.

  12. Double click photo for demo

  13. Wet Methods: Spray Systems for Bulk Materials

  14. Engineering Controls2. Ventilation • Portable tools with dust exhaust: • Surface Grinders • Disc Grinders (tuck pointing) • Crack chaser • Scarifier • Descaler • Power chipping tools • Retrofit Dust hoods (Dust Muzzle Video)

  15. Tuckpointing Note: Fall Protection Required

  16. Control by Ventilation: Tuckpointing

  17. Control by Ventilation: Tuckpointing

  18. Note: Safety Glasses Required • Control by Ventilation: Slab Cutting

  19. Control by Ventilation: Hand tools

  20. 3. Abrasive Blasting

  21. Engineering Controls:3. Substitute Abrasives • Coal slag (Low silica content, but may contain trace metals including arsenic) • Steel grit & steel shot • Aluminum oxide • Sodium Bicarbonate • (baking soda) • Dust Suppressed Sand • Frozen CO2 • Ag. Prod. (walnut shells, corn cobs)

  22. Substitute Abrasives: Blast and Recovery Systems • Permits multiple cycles of abrasive • Reduces cost of more expensive abrasives • Reduces fugitive emissions to Environment

  23. Alternate Abrasive Methods: Wet Blasting Similar to conventional air blasting • Water injected into air/abrasive stream, or • Water pressurized with abrasive • Work rate <50% of dry abrasive • Abrasive consumption <20% of dry • Better visibility, lower waste volume

  24. Alternative Blast Method: Enclosure

  25. Alternate Abrasive Methods: Water Jetting • 1. High Pressure • 10,000 – 25,000 psi • Removes most paint, rust, mill scale, chemical contaminants • 2. Ultra High Pressure • >25,000 psi • Removes all coatings • Processes can use vacuum shroud to retain/recycle water

  26. Alternate Abrasive Methods: Sponge Jet Blasting • Dry method, suppressed dust, minimal containment required • Light to heavy abrasion • Less aggressive cleaning • Eliminates the hazards of high pressure blasting

More Related