Chapter 7: Concepts to Prevent Fires and Explosion Flashcards
Capacitance is defined as
The ability to store electrical charge
What is the recommended residence time in an enlarged section of pipe to reduce charge buildup during liquid transfer?
Half the relaxation time.
To reduce charge buildup during the transfer of a liquid into a vessel, it is recommended to
Install a dip pipe
The primary purpose of bonding and grounding in electrostatic hazard prevention is to
Reduce the potential difference between objects
When handling flammable powders, what is the most effective way to prevent electrostatic ignitions?
Inerting the atmosphere.
To prevent lightning-like discharges in a vessel, it is recommended to
Reduce the vessel volume
.An effective way to increase the conductivity of a nonconducting organic liquid is to
Introduce a polar solvent
The “twice the relaxation time” rule provides a safety factor of
Four
Which of the following is NOT a special design feature to prevent electrostatic ignitions?
Relaxation
What is the purpose of a dip pipe in a liquid transfer system?
To prevent siphoning
What is the primary purpose of an inert atmosphere when handling solids with flammable vapors?
To prevent the ignition of flammable vapors
Which type of containers are recommended for solids containing flammable solvents?
Conductive and grounded containers
What is the primary function of explosion-proof housings for electrical equipment in XP areas?
To withstand an internal explosion and prevent the spread of combustion
Which of the following is not a class designation for flammable materials in the National Electrical Code (NEC)?
Class IV
What is the purpose of ventilation in preventing fires and explosions in chemical plants?
To dilute explosive vapors with air to prevent ignition
. Which type of ventilation system is recommended for open-air plants?
Natural ventilation
What is the primary function of sprinkler systems in fire prevention?
To suppress fires by applying water
What is the primary purpose of deluge systems in vessel protection?
To keep the vessel walls cool and prevent metal failure
What is the main purpose of monitors in chemical plants?
To provide a water source for firefighting
Which of the following is not a design technique for preventing fires and explosions in chemical plants?
Increase in process temperature
The flow of electricity produced by transmitting electrons from one surface to another through a flowing fluid or solid
Streaming Current
In Spark Discharge, the electrons migrate to leave the charged object at a single point and enter the second object at a single point because both are
Conductive
What charge is created when electrons flow over a material interface
Positive or Negative
The number of charge accumulation processes exist in a chemical facility that are relevant to hazardous electrostatic discharges?
Four
