MACHINE GUARDING
29 CFR 1910.211 to
1910.219
RULE OF THUMB
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Any machine part,
function, or process that
may cause injury must be
safeguarded.
REGULATORY
REQUIREMENTS
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Regulatory requirements found
in 29 CFR 1910, Subpart O
Applies to specific types of
equipment
Describes general requirements
WHERE MECHANICAL
HAZARDS OCCUR
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The point of operation
In the power
transmission apparatus
Other moving parts
REQUIREMENTS FOR
SAFEGUARDS
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Minimum general
requirements include:
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Prevent contact
Secure
Protect from falling objects
Create no new hazards
Create no interference
PREVENT CONTACT
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The safeguard must prevent hands, arms, and any
other part of an operator’s body from making contact
with dangerous moving parts.
The safeguarding system should eliminate the
possibility of the operator or another worker placing
parts of their bodies near hazardous moving parts.
SECURE
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Operators should not be able to easily
remove or tamper with safeguards
Guards should be made with a durable
material that will withstand normal wear
and tear.
Guards must be firmly secured to the
machine.
PROTECT FROM FALLING
PARTS
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Safeguard should ensure that no objects can
fall into moving parts.
A small tool dropped into a cycling machine
could become a projectile that would strike
and injure someone.
CREATE NO NEW
HAZARDS
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A safeguard defeats its own purpose if it
creates new hazards such as a jagged edge
or an unfinished surface that could cause a
laceration.
The edges of the guard, for example, should
be rolled or bolted so that sharp edges are
eliminated.
CREATE NO
INTERFERENCE
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A safeguard that impedes an operator from
performing the job quickly and comfortably
may be overridden or disregarded.
Proper safeguarding may actually enhance
efficiency since it relieves the operator’s
apprehensions about the injury.
TYPES OF GUARDS
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Fixed
Adjustable
Self-adjustable
FIXED GUARDS
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A permanent part of the machine
Not dependant on any other part to perform the
function
Usually made of sheet metal, screen bars or other
material which will withstand the anticipated impact
Considered the preferred type of guard
Simple and durable
ADJUSTABLE GUARDS
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Very flexible to accommodate various types of
stock
Manually adjusted
SELF-ADJUSTABLE
GUARDS
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The opening is determined by the movement of the
stock through the guard.
Does not always provide maximum protection.
MACHINES REQUIRING
GUARDING
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Bandsaws
Circular Saws
Grinders
Flat fillers
Transplanters
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Soil Mixers
Pot fillers
Fans
PTOs (Power Take Off)
BANDSAWS
CIRCULAR SAW
GRINDERS
FLAT FILLERS
FLAT FILLERS (CONT.)
TRANSPLANTERS
SOIL MIXERS
POT FILLERS
FANS
POWER TAKE OFF (PTO)
SHIELDS/GUARDS
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Every component of the
PTO should be shielded
for maximum protection.
For this reason,
engineers have
developed four different
types of shields:
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master shields
stub shaft shields
shaft shields
implement shields.
POWER TAKE OFF
SHIELDS/GUARDS (Cont.)
PRECAUTIONS WITH
PTO SHIELDS/GUARDS
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Never remove PTO shields.
Shield all PTOs completely by installing
shaft shields, master shields, and
implement shields.
Always replace bent or damaged guards.
Safety decals must be present on the
tractor and PTO driven equipment.
Do not perform maintenance on any
equipment until the engine is shut off and
the PTO and other machinery parts have
completely stopped moving.
EXAMPLES OF POWER
TAKE OFF GUARDING
WHEN IS EMPLOYEE
TRAINING REQUIRED?
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For new operators and maintenance or setup
personnel
When any new or altered safeguards are put
in service
When operators are assigned to a new
machine or operation
REQUIREMENTS FOR
EMPLOYEE TRAINING
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Description and identification
of hazards associated with
particular machines
The safeguards themselves,
how they provide protection,
and the hazards for which
they are intended
How to use the safeguards
and why
REQUIREMENTS FOR
EMPLOYEE TRAINING (Cont.)
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How and under what circumstances safeguards can
be removed, and by whom (in most cases, repair or
maintenance personnel only)
What to do if a safeguard is damaged, missing or
unable to provide adequate protection
SUMMARY
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Where mechanical hazards occur
Requirements for safeguards
Types of guards
Machines requiring guarding (pictures)
Employee training
REFERENCES FOR
MORE INFORMATION
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http://www.cdc.gov/nasd/menu/topic/machine
ry_guarding.html
http://ohioline.osu.edu/aex-fact/0994_2.html
http://www.osha.gov/SLTC/machineguarding/
index.html#eTools
LET’S SEE WHAT
YOU’VE LEARNED
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Quiz time!!!
QUESTION 1
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Mechanical hazards occur at the point of
operation, in the power transmission
apparatus, and ___________________.
Answer: Mechanical hazards occur at the
point of operation, in the power transmission
apparatus, and in any other moving parts.
QUESTION 2
Any moving part on a piece of
equipment that could injure an
employee should be guarded.
True or False
z Answer: True. All moving parts
that create a hazard should be
guarded.
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QUESTION 3
Employees should be trained when new
safeguards are put in service.
True or False
z Answer: True. Employees should be trained
when new or altered safeguards are put in
service.
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QUESTION 4
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The blades of a fan located less
than 7 feet from the ground shall be
guarded and the guard shall have
openings no larger than _______
inch(es).
Answer: The blades of a fan located
less than 7 feet from the ground
shall be guarded and the guard
shall have openings no larger than
one-half (1/2) inch.
QUESTION 5
As long as the guards remain in
place, operators should not be
trained on machine guarding.
True or False
z Answer: False. If operators work
with equipment containing
safeguards, they should be
adequately trained on how to use
them.
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QUESTION 6
Some guards may not prevent parts of the
worker’s body and clothing from making
contact with dangerous parts.
True or False
z Answer: False. All guards must prevent
contact.
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QUESTION 7
Fixed guards are a permanent part of the
machine.
True or False
z Answer: True. Fixed guards are a
permanent part of the machine and to deter
easy removal, a fixed guard must require the
aid of an appropriate tool to open, remove,
replace, perform maintenance or repair work.
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QUESTION 8
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Name one minimum general requirement for
safeguards.
Answers
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prevent contact
be secure
protect from falling parts
create no new hazards
create no interference
QUESTION 9
Keep any shielding on PTO’s in place or replace
immediately after servicing.
True or False
z Answer: True. If the removal of a guard is absolutely
necessary for maintenance or repair, replace the
guard immediately when finished.
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QUESTION 10
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List the types of guards common to our
industry.
Answer: Fixed, adjustable, and selfadjustable.
THE END