For Midterms Flashcards
✓The objective of this issuance is to protect every workingman against the dangers of injury,
Occupational safety and health standards (OSHS)
✓Purpose
“To help reduce the risk of injuries
and fatalities by providing practical
guidance on farm health and
safety…
”
OSHS
the primary goal of _______ is to
prevent accidents, injuries, and fatalities
that may occur during the use,
maintenance, or repair of industrial
machines.
Machine safety
refers to the practices, procedures, and
technologies implemented to ensure the
well-being of individuals and the safe
operation of machinery and equipment.
Machine Safety
It is
less likely to occur if the operator checks
the conditions of the machine seasonally
and again before each day’s work.
Improper Maintenance of Machinery
When human judgement (or error) forces a
machine beyond its designed capability
limits, a machine operator is in a
hazardous position, because the machine
does not function efficiently.
Improper Use of Machinery
A structure on a farm tractor or self-
propelled machine that limits most
equipment roll-overs to 90 degrees
and protects the operator within the
frame of safety if he/she is wearing
the seatbelt.
Roll-over Protective
Structure (ROPs):
A shaft that allows transmission of power
from a farm tractor to a piece of
equipment attached to it.
Power Take-off (PTO):
Example of Between rotating and tangentially
moving parts
belt drives.
Example of Rotating parts
operating alone
couplings.
Example of Running nips between
parts rotating in
opposite directions
gear wheels.
This must be used only where an
immediate hazard exists.
➢Danger Sign
shall be used only to
warn against potential hazards or to
caution against unsafe practices.
Caution sign
signs reminds
workers to follow safety
procedures and safety policies.
Safety Instruction Signs
Raise the arm vertically overhead, palm to the
front, and rotate in large horizontal circles.
COME TO ME.
Place palms at ear level facing head and move laterally
inward to indicate remaining distance to go.
THIS FAR TO GO.
To signal this, move arm in a circle at waist
level as though you were cranking an engine.
START THE ENGINE.
To signal this extend
arm horizontally at your side, palm down, and wave
arm downward (45 degrees minimum) several times,
keeping arm straight. Don’t move arm above
horizontal.
SLOW IT DOWN. DECREASE SPEED.
Face the desired direction of movement; hold the arm
extended to the rear; then swing it overhead and forward
in the direction of desired movement until it is horizontal,
palm down.
MOVE OUT-TAKE OFF.
Point toward person(s), vehicles(s), unit(s), beckon by holding
the arm horizontally to the front, palm up, and motioning
toward the body.
MOVE FOWARD ME-FOLLOW ME.
Raise the hand to the shoulder, fist closed, thrust the fist
upward to the full extent of the a
SPEED IT UP- INCREASE SPEED.
Raise hand upward to the full extent of the arm, palm to the
front. Hold that position until the signal is understood.
STOP.
Make circular motion with either
hand at neck level.
STOP THE ENGINE.
Make circular motion with either
hand at head level or pointing upward
RAISE EQUIPMENT.
Make circular motion with either hand pointing to the
ground.
LOWER EQUIPMENT.
“Safety is as simple as ABC
Always Be Careful”
ANSI
American National Standards Institute
OSHA
Occupational Safety and Health
Administration
are used to describe the
standard use of colors for safety purposes in
the workplace.
Safety Colors
How many Basic Color-Coding Requirements from
OSHA
4
What are the Basic Color-Coding Requirements from
OSHA
- Danger
- Warning
- Caution
- Biological Hazards
➢OSHA requires these signs to be red or predominantly
red.
Danger
signs are only used when there is an immediate
risk to the life and health of an employee
Danger
this category is for when there is a risk, but it is not as
severe or immediate as when danger is used.
Warning
This sign must use the color yellow.
Caution
This category is for alerting people to a
potential risk.
Caution
This sign must be color orange
Warning
the color to use is fluorescent orange or an
orange-red color.
Biological Hazards
Color used for hazards
related to striking, falling, slipping, tripping, pinch
points, and other similar hazards that are common
in many manufacturing or warehouse facilities
Yellow
this should be used when there is a
fire-related hazard in an area. What color
Red
This can also be
used to alert people to stop, which is essential for
indoor or outdoor driving and other situations. What color
Red
is a private nonprofit organization that
oversees the development of voluntary
consensus standards for products, services,
processes, systems, and personnel in the
United States.
ANSI
Color used to alert people of
dangerous parts on a machine or piece of
equipment. The danger could be from a
crush, cut, shock hazard, or any other
hazard that could physically harm people
or the facility.
Orange
Color used on any safety signs, labels,
or other objects to signify danger or to
alert people that they need to stop.
Red
Color used to alert people to the
presence of an emergency egress. This
provides directions for those needing to
escape areas during emergency events.
Green
Color Anywhere that caution needs
to be used,
Yellow
Color is used on signs and labels that provide information and suggestions
about a particular item or location. This information doesn’t necessarily have
to be safety related.
Blue
Color reserved for future use by ANSI.
Gray
Color reserved by ANSI for future use, but it has
become a de facto standard for radiation hazards through popular use.
Purple
used for guiding traffic or telling people which direction
to go. These colors can also be for housekeeping practices in the facility.
Black & White
Color for toxic and/or corrosive solutions.
Orange
Color used for any combustible liquids or gases.
Brown
Color used for flammable liquids or gases.
Yellow
Color used for compressed air.
Blue
used to label water pipes. Note that this can be
water used for coolant, waste, or other things, so it is not necessarily
potable.
Green
Color used for fire-quenching liquids or solutions.
Red
hard hats for carpenters and other
technical workers.
Blue
hard hats for construction
workers and laborers.
Yellow
hats for site managers,
engineers, or supervisors.
White
hard hat for crane operators.
Orange
hard hats for safety inspectors.
Green
hard hat for fire marshals.
Red
hard hat for welders and other workers
who are exposed to high heat applications .
Brown
hard hats for site visitors.
Grey
are any tools or machine powered by an
external source of energy, such as electricity
or compressed air.
➢ extremely hazardous when used
improperly.
Power Tools
…greatest hazards posed
by this tools result from misuse
and improper maintenance.
Hand Tools
➢are tools that are powered manually.
Hand Tools
tools that are usually operated
with gasoline. The most serious hazard
associated with the use of fuel-powered
tools comes from fuel vapors that can burn
or explode and give off dangerous exhaust
fumes.
Liquid Fuel Tools
➢are powered by compressed air and include
chippers, drills, hammers, and sanders.
Pneumatic Tools
tools that operate like a
loaded gun and must be treated with
extreme caution. In fact, they are so
dangerous that they must be operated
only by specially trained employees.
Powder-Actuated Tools
tools that use pressurized fluid to operate
Hydraulic Power Tools
coniferous trees
Softwood
deciduous trees
Hardwood
is a commonly used construction
material in many parts of the
world because of its reasonable
cost, ease of working, attractive
appearance and adequate life if
protected from moisture and
insects.
Wood
Properties of woods are in terms of
Mechanical and
✓Physical Property
hardwood vs softwood
This covers a large area of heartwood
Hardwood
hardwood vs softwood
This cover less heartwood
Softwood
hardwood vs softwood
Sapwood area is smaller
Hardwood
hardwood vs softwood
Sapwood area is larger
Softwood
hardwood vs softwood
Dark in color
Hardwood
hardwood vs softwood
Light in color
Softwood
hardwood vs softwood
Growth rings are close
Hardwood
hardwood vs softwood
Growth rings are far apart
Softwood
hardwood vs softwood
Poor fire resistance
Hardwood
hardwood vs softwood
Better fire resistance
Softwood
is also quite closely related to
density.
Strength
Not only is related to the
species, but also to moisture content
(MC) and defects.
Strength
in wood is its ability to resist breaking
when it is used in beams and columns.
Strength
What is Janka Method
Austrian-born American researcher
Gabriel Janka (1864–1932)
➢ 11.28-millimeter-diameter steel ball
halfway into a sample of wood.
➢ Sample size: 80mm × 150mm × 6-
8mm
➢ MC 12%
is the resistance to denting and
wear. While hardwoods are more
difficult to work, they are required
for tools, tool handles, flooring and
other applications subject to wear,
or where a high polish is desired.
Hardness
This wood will deflect considerably before
breaking. Even after fracturing, the
fibers tend to hang together and
resist separation. These are
resistant to shock loading.
Tough woods
resist deflection or bending when
loaded. These woods are not necessarily
very strong. They may resist bending
up to a point and then break
suddenly.
Woods that are stiff
is deformity in wood occurring
when the moisture content of
different parts of a piece of wood
changes unevenly.
Warping
is the twisting, bending or bowing
distortions shown by some
woods.
Warping
Nail-holding resistance is also known as
nail withdrawal
resistance
Pre-boring to 75% of the nail size avoids
splitting.
Nail-holding resistance
also known as nail withdrawal
resistance, is an important property of
wood, especially in construction
applications where nails are commonly
used to join pieces together
Nail-holding resistance
also known as wood durability,
refers to its ability to resist
degradation caused by fungi,
bacteria, and insects.
Natural-decay resistance
refers to how easily a particular type
of wood can be cut, shaped
Workability
Physical Property of wood
- Color
- Luster/Grain
- Texture
- Density
Mechanical Properties of woods
Strength
Hardness
Woods that are stiff
Tough woods
Warping
Nail-holding resistance
The workability
Natural-decay resistance
Paint-holding
also referred to as adhesion,
refers to how well paint adheres
to the surface of wood and resists
peeling, cracking, or flaking over
time.
Paint-holding
This is primarily
due to the presence of different
pigments and extractives within the
wood.
Color
This color can be soft or
hard.
Medium-colored woods (reddish-brown, yellowish-brown, and
even some grays)
The color of wood can be affected by
several factors these are the
➢age, exposure to sunlight, and the
presence of stains or dyes.
It describes how much light the
wood reflects, and how well it
showcases its natural beauty and
grain patterns.
Luster/Grain
Luster/Grain is sometimes referred to as
Sheen
refers to the reflectivity of light
from the wood’s surface.
Luster/Grain
It is influenced by factors like
wood density, grain pattern, and
growth characteristics.
Texture
refers to the surface feel of the
wood, which can be smooth,
rough, grainy, or even figured
(with unique patterns)
Texture
more textured and uneven feel
Wavy, curly, or interlocked grain
smoother and
more even texture
Straight grain
When density or specific gravity is =
0.36 wood is called
light.
When density or specific gravity is
<0.36 g/cm3 wood is called
very
light.
When density or specific gravity is >
0.5, wood is
heavy.
When density or specific gravity is
0.36 – 0.5, wood is
moderately
heavy.
is directly related to the
amount of wood substance packed
into a specific volume.
Density
Refers to the mass per unit volume
of wood.
Density
___ woods are
generally heavier, harder, and
more durable but also more
challenging to work with.
Denser
it’s a metal
created by combining two or more
elements.
Steel
is a specific alloy
Steel
is a general
category encompassing various
elements and their alloys exhibiting
certain characteristic properties.
Metal
the primary elements of steel are
iron and carbon.
The ferrous
metals which find their common
are:
- Cast
- Steel
are those metals
in which the chief constituent is
iron. Besides iron, other constituent
like carbon, Sulphur, manganese
and phosphorus etc.
Ferrous Metals
Ferrous Metals is made Besides iron, other constituent
like
carbon, Sulphur, manganese
and phosphorus etc.
The
important non-ferrous metals are
copper, lead, tin, zinc and
aluminum.
are those
which do not contain iron and are
widely in building industry.
Non-Ferrous Metals
It is
hard and brittle.
Cast Iron
Is a ferrous alloy which has more
than 2% carbon on it. Though it can
have any % of carbon between 2% to
6.67%, but practically it is in between
2% to 4% only.
Cast Iron
Increase hardenability, wear
resistance, corrosion and oxidation
resistance.
Chromium
Increase resistance to wear
and abrasions.
Manganese
it increases hot hardness and
hot strength.
Tungsten
Increases tensile strength
Nickel
increases hardenability and
electrical resistivity
Silicon
increase hardenability
Molybdenum
It reduces hardenability and
increases ductility, which results in increased
impact strength
Niobium
works as
deoxidizer in steel
Aluminum & Titanium
it reduces hardenability and resist
at elevated temperatures
Cobalt
Cast iron’s melting points is about
1200°C
steel that contains
carbon from 1.5%
Very hard steel
Steel that I contains
carbon from 0.15%
Very soft steel
The higher the percentage of the _____
the harder and the tougher the steel.
Carbon
carbon contents range from 0.6-1.5%
High carbon steel or hard steel
carbon contents
range from 0.3 – 0.6%
Low or medium carbon steel
having % of
carbon below 0.15%
Very low carbon steel
Four main kinds of fabrication
techniques:
- Casting
- Forming
- Machining
- Welding/Joining
works is a manufacturing process used
to create objects or shape by pouring in
liquid metal into a mold that holds the
required shape and letting harden the
metal without external pressure.
Casting
when:
(a) product is large and/or complex
shapes
(b) material is low in ductility
This fabrication technique is used
Metal casting
Types of Casting:
- Sand casting
- Investment casting
- Die casting
- Continuous casting
A metallic piece is subjected to external
pressures to induce deformation; thus,
material acquires a desired shape.
Forming
A process in which the desired size and
shape are obtained through the
deformation of metals plastically under
the action of externally applied forces.
Forming
Types of
forming:
➢ Rolling
➢ Extrusion
➢ Drawing
➢ Forging
➢ Bending
Two processes of
metal forming:
1) Cold forming
2) Hot forming
Types of machining:
- Turning
- Milling
- Drilling
- Grinding
- Electromachining (EDM)
➢ It plays a crucial role in various
industries, enabling the production of
diverse and intricate parts with high
precision and accuracy.
Machining
manufacturing process used to create
desired shapes and features on a
workpiece by removing material in a
controlled manner.
Machining
Types of welding:
➢ Arc Welding
➢ Oxyfuel gas welding
➢ Laser beam welding
➢ Resistance welding
It’s a versatile and widely used technique
across various industries, enabling the creation
of strong and durable structures.
Welding
a fabrication process that joins materials,
typically metals or thermoplastics, by using
heat to melt the parts together and allowing
them to cool and solidify, forming a
permanent bond
Welding
Utilizes a combination of oxygen and a fuel gas (like acetylene) to produce a
flame that melts the metal.
Oxyfuel gas Welding
Uses an electric arc generated between
an electrode and the workpiece to create
intense heat for melting.
Arc Welding
Employs a highly concentrated laser beam to melt the metal precisely.
Laser Beam Welding
refers to the ability of a material to be joined using a welding
process.
Weldability
Uses electrical resistance to generate
heat at the joint between the metals
being joined.
Resistance Welding
The word ‘Polymer’ is coined from two Greek words what is this?
poly means many and mer means unit or part.
are the high molecular weight compounds obtained by
repeated union of simple molecules
Polymers
The repeating structural units are derived from some
simple and reactive molecules known as ____
and are linked to each other by covalent bonds.
monomers
is defined as very large molecules having high
molecular mass (macromolecules) which are formed by
joining of repeating structural units on a large scale.
Polymer
This process of formation of polymers from respective
monomers is called _____.
polymerization
[1] by Source
[2] by Backbone of the chain
[3] by Structure
[4] by Composition
[5] by Mode of Polymerization
[6] by Molecular force
Classification of polymers based on some special considerations. The
following are some of the common classifications of polymers:
[1] by Source
[2] by Backbone of the chain
[3] by Structure
[4] by Composition
[5] by Mode of Polymerization
[6] by Molecular force
3 polymers based on source
Natural Polymers:
Synthetic Polymers
Semi-synthetic Polymers
are man-made materials
created through chemical reactions. They are
typically non-biodegradable and derived from
fossil fuels.
Synthetic Polymers
These polymers are found in
plants and animals.
Natural Polymers:
are derived from
natural polymers that have been chemically
modified to enhance certain properties. They
bridge the gap between natural and synthetic
Polymers
Semi-synthetic Polymers
Polymers Based on Molecular Force:
- Elastomers
- Fibers
- Liquid Resins
- Plastics
- Thermoplastic
- Thermosetting plastic
possess weak intermolecular forces
between their chains.
Elastomers (Rubbery Polymers):
Types of elastomers (rubbery polymers)
➢ Natural rubber (polyisoprene)
➢ Styrene-butadiene rubber (SBR)
➢ Nitrile rubber (NBR)
Elastomers (Rubbery Polymers) possess weak intermolecular forces
between their chains. These forces may
include _____ and ____
van der Waals interactions and
dipole-dipole interactions.
2 types of plastic
Thermoplastics and Thermosets
soften when heated and harden on cooling
(totally reversible)
Thermoplastics
exhibit intermolecular forces of intermediate
strength typically van der Waals interactions and
some hydrogen bonding in specific cases.
Thermoplastics
The number is
a ______
developed by the Society of the Plastics
Industry to identify what materials/chemicals
are in each plastic item, how biodegradable it is,
the level of leaching, and for sorting purposes
.
resin identification code
The number is
a resin identification code
developed by the _____ to identify what materials/chemicals
are in each plastic item, how biodegradable it is,
the level of leaching, and for sorting purposes
.
Society of the Plastics
Industry
is mainly used in
applications of packaging and textile
production.
Polyethylene Terephthalate (PETE or PET)
Polyethylene Terephthalate (PETE or PET)
is a polymer produced through the
polymerization of ___ & ____
ethylene glycol and
terephthalic acid.
resists a wide range of chemicals,
making it suitable for various
applications.
High-density Polyethylene (HDPE)
is a thermoplastic polymer made
from petroleum. It is one of the most
versatile plastic materials.
High-density Polyethylene (HDPE)
is
one of the most widely produced
synthetic polymers globally. It’s
valued for its versatility,
affordability, and a range of useful
properties.
Polyvinyl Chloride
➢ often abbreviated as PVC or vinyl,
is noted for its low
temperature flexibility, toughness,
and corrosion resistance.
➢ It is not suited for applications where
stiffness, high temperature resistance
and structural strength are required.
Low-density Polyethylene (LDPE)
