Grounding & Bonding Flashcards
What does the standard for competence of responders to hazardous materials/weapons of mass destruction recommend grounding and bonding procedures for?
The transfer of flammable and combustible products from tank cars, highway, cargo tanks, and other products they can give a flammable gases in vapors when heated or contaminated
Category, 1 or 2 flammable will liquids, or category 3 flammable liquids with the flashpoint below 100°F (37.8°C) shall not be dispensed in the containers unless nozzle and container electrically interconnected. True or false.
True
Volts
The pressure that forces the flow of electrons from one point to another
Electricity
The flow of electrons
Amperes
The amount of current through a point in one second
Ohms
The amount of resistance to the flow of the current. Calculated using ohms law. Resistance equals volts/current.
Static electricity
Electricity present on the surface of a non-conductive body were the electricity is trapped, or prevented from escaping
Static transfer is equalization of electrical charges. What are the two types?
Conductive where the objects are touching each other.
- inductive, where the objects are not touching each other, and there’s a spark, jumping from one object to the other.
What is the definition of a flammable liquid?
A liquid having a flashpoint of less than 140°F (DOT) or 100°F (NFPA & OSHA)
What is the definition of a combustible liquid?
A liquid having a flashpoint of greater than 140°F (DOT) or 100°F (NFPA & OSHA)
What is the definition of grounding?
The connection of the object to the earth
Conductor
An object or substance in which electricity can freely move through such as metals
Insulator or nonconductor
Is a material the electricity has difficulty flowing through
What is the definition of bonding?
The connection of two or more conductive objects together by the means of a conductor (wire cable)
What is the grounding and bonding system?
The connection of the conductive objects together, and each separately connected to the earth
What is the relaxation time?
The amount of time it takes an object to discharge the static, build up after grounding and bonding.
It depends on volume and chemical properties. Rule of thumb. Allow 15 minutes relaxation time.
Equipotential plane
Conductive parts are bonded together, they effectively illuminate the difference of voltage potential that may exist between the individual conductive parts in that reduces static hazard
How does weather affect ground effect
Approximately 20 times more static is generated when humidity is 33% then when it is 65%
Proximately 300 times more static if humidity is only 20%
How does soil type affect ground field?
Resistance varies , on composition of moisture content
-Mostly clay resistance should be low
-if mostly sand grounding may be difficult
-rule of thumb: the dryer, the soil, the more resistance it has
How does temperature affect grounding?
As temperature goes up, the resistance, lowers
What conditions need to happen for ignition from static electricity?
- Generation of static electricity.
- Accumulation of static charge with no means to discharge.
- Spark discharge of adequate energy.
- Spark discharge in an ignitable atmosphere
And all bonding operations involving appliances where is the first connection made?
The damaged unit
P379
When doing a liquid transfer from damaged truck, some liquid will remain in the bottom of the container since the pump can only remove liquid to the bottom of the reduction or dip tube. What is the product remaining refer to as?
The heel
P381
Up to what pressure vacuum trucks designed to operate?
- Psi.
P382
