AG 4343 Ch. 11

What kind of welding hood is most efficient?

Double canopy hood

What is practical to design for a single welding booth?

Hood and exhaust system

What is practical design for a large number of booths or welders in one work area?

Exhaust the entire room

What kind of ventilation should be above a welding table?

Hood ventilation

Who can you consult about an air intake system?

Ventilation engineer

What gas must be removed from the lab?

Carbon monoxide

Where can exhaust gas removal systems be located?

Underground or overhead

What are the two types of underground tubes used in an exhaust gas removal system?

Concealed or non-concealed

Where are the underground concealed tubes for the exhaust gas removal system located?

Inside the duct under the floor

Where are the underground non-concealed tubes for the exhaust gas removal system located?

Positioned in the duct opening at floor level

What are the tubes used in an exhaust gas removal system made of?

Galvanized steel

Where are flexible tubes for the exhaust gas removal system located?

Suspended from the duct

Where can flexible tubes on the overhead exhaust gas removal system extend to?

Extend to the ceiling or wall

What can be used in welding booths?

Flexible drops

What is a significant hazard in the agricultural lab?

Dust

What is a result of some dust set ups?

Inflammatory process leading to lunch tissue changes

What kind of problem is dust and dirt?

Housekeeping problem

What are the four basic types of dust collectors?

* Mechanical (generally a centrifugal separator of low or high pressure)
* Fabric (cloth filter)
* Wet
* Electrical precipitator

What is this dust collection term: CFM?

Air voluntary in __cubic feet per minute__

What is this dust collection term: FPM?

Velocity of air in __feet per minute__

What is this dust collection term: SP?

__Static pressure__ expressed in inches water-gage

What are the most common types of dust collectors?

Centrifugal and fabric types

What is the best way to fight a fire?

Prevention

What are the 3 components required for a fire?

Fuel, heat, and air

Fire extinguishers must be approved by ___________.

Underwriters Laboratory, Inc. (UL) and/or Factory Mutual (FM)

How are fire extinguishers rated?

By their fire extinguishing potential

What are Class A fires?

Fires involving paper, wood, cloth, rubber, plastic, and similar materials

What are Class B fires?

Fires involving burning liquids such as gasoline, oils, grease, thinners, paints, cooking fats

What are Class C fires?

Fires involving electrical equipment such as motors, switches, appliances, and other components

What are Class D fires?

Involves burning metals such as magnesium, titanium, and sodium

How do you put out Class A fires?

Can be quenched by water or insulated by general purpose dry chemicals

How do you put out Class B fires?

Smothering action is efficient and/or practical

How do you put out Class C fires?

Nonconducting extinguisher agent is required

How do you put out Class A fires?

With specialized equipment and techniques

What are the types of fire extinguishers?

* Water
* Foam
* Carbon dioxide
* Dry chemical

What type of fires is a foam fire extinguisher recommended for?

Class A and B

What type of fires is a carbon dioxide fire extinguisher recommended for?

Class B and C

What type of fires is a dry chemical fire extinguisher recommended for?

Class B and C

How often should you check fire extinguishers?

At least once a year

Where should fire blankets be located in the lab?

Near the welding area

What types of fire extinguishers should be available for instruction areas away from the lab?

Portable fire extinguishers

What are schools required to have?

Fire drills

What is the proper criterion of shock intensity (instead of voltage)?

Current

What are the three parts of Ohm’s law?

* A (amperes)
* V (volts)
* R (ohms)

The number of amperes which flow in the circuit will be directly proportional to what?

Proportional to the pressure in voltage and inversely proportional to the resistance in ohms

Amperes (A) = ?

Voltage (V) ÷ Ohms Resistance (R)

What is the severity of shock dependent on?

Dependent on the rate of current flow, path and current flow, and length of time the body is in the circuit

What does the GFCI detect?

Detects an imbalance of current flow in a circuit and trips in the circuit

The National Electrical Code (NEC) requires the use of _______ in several circuits.

GFCI’s

What is required for extension cords?

GFCI unit

Protection cannot be guaranteed if __________________ of the wiring code has not been followed.

GFCI proper polarity

The amount of current flowing through the body is governed by what?

Governed by the resistance of the body

What does GFCI stand for?

Ground Fault Circuit Interrupter

What does a GFCI do?

Has a sensing device which detects the current flow to the electrical power tool, etc.

Are safety colors (more or less) standardized?

Yes

What is the purpose of safety colors?

To promote safety and reduce the number of accidents

What are the standard safety colors?

Red, orange, yellow, blue, and green

What is safety ORANGE used for?

Designating dangerous parts of machines or energized equipment

What is safety YELLOW used for?

Designating caution or any part that may need adjustment before using the machine

What color is a radiation hazard system?

Safety yellow and safety black

What is safety BLUE used for?

Informational signs

What is safety BLUE used for?

Designating safety

Where can you see safety BLUE?

* Medical first aid kits
* Gas masks
* Stretchers
* Safety deluge showers
* Safety bulletin boards

What is IVORY used for?

Spotlight color to improve visibility

What should be used for lane application?

Yellow vinyl tape

Where do piping sytems have color?

At their outlets

Lighting includes both _________ __and__ _________ sources.

__Natural__ and __artificial__ sources

What is influenced by color?

Emotional comfort

Safety colors influence student _________ __and__ _________.

Reaction and production

What kind of paint marks danger spots?

Luminescent paints

What should be color coded?

Shop tools and equipment