OVERVIEW COMBUSTIBLE DUST QUIZ: Management Level Produced under OSHA Susan Harwood Grant SH-19509-09.

OVERVIEW COMBUSTIBLE DUST QUIZ: Management Level

Produced under OSHA Susan Harwood GrantSH-19509-09

• What SIZE of dust is Combustible?

• ANSWER: What is Dust less than 420 microns in size. (passing a #40 sieve).

HAZARD ASSESSMENTSHAZARD ASSESSMENTS

• What is the BEST WAY to prevent, Fire Hazards, Deflagration, or Explosion?

• ANSWER: What is a Self-Assessment, Self-Scoring, INSPECTION CHECKLIST?


• What is the NFPA Code that serves as the GO-NO GO DECISION POINT for the Inspection Checklist?

• ANSWER: What is NFPA 91 & 654? IF ONLY non-combustible particulate solids are present, the “checklist” does not apply!


• What are the things OSHA looks for while on a Combustible Dust inspection?

• ANSWER: What is dust presence and accumulation? Dust that is present at greater than 5% of surface area, 1/32 of an inch accumulation, and accumulation on overhead surfaces will get you cited!


• What is a SECONDARY EXPLOSION?

• ANSWER: What is an explosion of dust that gets shaken loose from overhead accumulations because of the primary explosion?


• What’s a passive way to prevent dust accumulation on walls?

• ANSWER: What are OUTWARDLY SLOPING WALLS? They’re designed with a curve away from walls so that dust slides off.

PRACTICAL HOUSEKEEPING & IGNITION SOURCE CONTROL


• What are the benefits of FREQUENT dust clean-up?

• ANSWER: What is preventing dust accumulation.



• Name as many sources of mechanical friction that can generate heat very quickly?

• ANSWER: What are Conveyor Belts, or Metal on Metal or failing Bearings?



• Name as many small and portable IGNITION SOURCES as you can remember…

• ANSWER: What is open flame from matches, lighters, space heaters, heat guns, and welding equipment?



• Name as many ELECTRICAL sources of ignition as you can you remember…

• ANSWER: What are exposed electrical wires, damaged electrical equipment and wires, static electricity, or open breaker panels?



• What is the National Fire Protection Association?

• ANSWER: What is an Association that researches and publish standards based on industry experience and best practices?

NFPA ENGINEERING CONTROLS, BUILDING DESIGN, EXPLOSION PROTECTION


• Under NFPA, must engineering controls for Deflagration prevention be “Acceptance Tested”?

• ANSWER: What is YES



• Should controls be on a periodic inspection and maintenance schedule?

• ANSWER: What is YES.



• MUST engineering controls be checked against NFPA requirements for Operation, Maintenance, and Safety Requirements?

• ANSWER: What is YES

NFPA ENGINEERING CONTROLS, BUILDING DESIGN, EXPLOSION PROTECTIOn

NFPA ENGINEERING CONTROLS, BUILDING DESIGN, EXPLOSION PROTECTIOn

• Name some types of deflagration engineering controls or components listed in the NFPA codes…

• ANSWER: What is 1-Oxidant reduction concentration (which prevents combustion), 2-Passive Isolation System (isolates system problems), Pre-Deflagration detection system , 4-Deflagration Suppression and Explosion venting.



• What is a Deflagration Condition Assessment?

• ANSWER: What is analyzing conditions to see if you have a potential for a deflagration or dust explosion.



• What MUST you do IF you are a wood processing location and you’re NOT SURE if you meet NFPA Code requirements relating to wood dust hazard controls?

• ANSWER: What is REVIEW NFPA CODES in detail, and DEVELOP A PLAN of ACTION to prevent hazards.



• Name some NFPA Standards BY NUMBER and purpose...

• ANSWER What is NFPA:• 68 – Explosion Protection by Deflagration Venting• 69 – Explosion Prevention Systems• 70 – National Electrical Code • 77 – Recommended Practice on Static Electricity• 79 – Electrical Standard for Industrial Machinery• 499 – Combustible Dusts-Classified Locations-Chemical Process Areas• 654 – Prevention of Fire & Dust Explosions, Handling of Combustible

Solids• 664 – Prevention of Fires & Explosions in Wood Processing and Wood

Working Facilities.



• What are some PRACTICAL WAYS to control Deflagrations?

• ANSWER What are ENGINEERED SYSTEMS that ISOLATE, REDIRECT, CONTAIN, or EXTINGUISH deflagrations within enclosed process equipment?



• What is the MOST CRITICAL component for ANY engineered system?

• ANSWER: What is OPERATOR TRAINING! Employees who control and interpret the information from engineering controls MUST know how to properly operate the system for start-up, operation, shut-down, and ANY other condition!



• What is a THERMOGRAPHIC IMAGER?

• ANSWER: What is an Infrared Camera. (Remember that the detection of infrared radiation is converted to visual images with a temperature scale. This analytical method allows you to detect sources of ignition using visual means).

DETECTING HAZARDOUS CONDITIONS with THERMOGRAPHIC IMAGERY


• What is the AUTO-IGNITION temperature of WOOD DUST?

• ANSWER: What is 399 *F to 500 *F. (Remember, contact with wood dust at this temperature will cause it to ignite)!



• What is the surface temperature range of a Metal Halide Lamp?

• ANSWER: What is 400 *F to 700 *F. Also, failure of this type of light source is “catastrophic”, it can shatter and explode.



• A Halogen lamp is uncovered and wood dust is suspended in air. Using TI, the lamp’s surface temperature was determined to be at 552 degrees Fahrenheit – Is this ABOVE or BELOW the auto-ignition temperature of wood dust?

• ANSWER: What is ABOVE it? The auto-ignition temperature for wood dust is 399 to 500 degrees Fahrenheit, and this is an IGNITION SOURCE. With dust suspended in air, DEFLAGRATION CONDITIONS exist.



• Wood dust has accumulated next to an electrical panel, and a Thermographic Image of the panel shows a surface temperature of 700 degrees Fahrenheit. Is it a cause for concern?

• ANSWER: What is YES! In this case, the surface temperature alone is enough to auto-ignite the dust! You have FIRE TRIANGLE conditions at this point, and will have a deflagration hazard if dust becomes suspended in air.



OVERVIEW COMBUSTIBLE DUST QUIZ: Management Level Produced under OSHA Susan Harwood Grant SH-19509-09.

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