Mechanical Hazard

Question 1

What are OSHA’s top 10 violations?

Answer 1

1. Fall protection
2. Scaffolding
3. Hazard communication
4. Respiratory protection
5. lockout/tagout
6. Electrical -wiring
7. Powered Industrial Trucks
8. Ladders
9. Electrical-general requirements
10. Machine Guarding -General requirements

Question 2

What are common mechanical injuries?

Answer 2

· cutting and tearing
· shearing
· crushing
· straining and spraining
· puncturing

Question 3

What is Point of operation?

Answer 3

The point where work is performed on the material (cutting, shaping, boring, or forming of stock must be guarded

Question 4

What is Power Transmission

Answer 4

-All components transmitting energy to the part of the machine performing the work

-flywheels, pulleys, belts, connecting rods, coupling cams, spindles, chains, cranks, gears etc.

Question 5

What are Rotating Hazards?

Answer 5

-collars, couplings, cams, clutches, flywheels, shaft ends, spindles, horizontal or verticle shafts
· drill bit is an example

Question 6

What are Nip Points?

Answer 6

1. Parts are rotating in opposite direction with parallel axes can cause nip points
2. Nip Points are cause between rotating and tangentially moving parts
3. Between rotating and fixed parts which create a shearing, crushing or abrasive action

on belt conveyers the most important danger points are the nip points

Question 7

What is Reciprocating?

Answer 7

· Hazards caused when a worker may be stuck or caught between a moving and stationary part during:
-back and forth motion
-up and down motion

Question 8

What is Transverse?

Answer 8

· Hazards caused when a worker may be stuck or caught in a pinch or shear point.
· Ex: conveyor type systems at saw mills, manufacturing assembly lines etc.

Question 9

How are the hazards of Punching, shearing, and Bending Actions called?

Answer 9

· When power is applied to a slide or knife for blanking, drawing, stamping, shearing, or forming metal or other materials
· Hazards exists at the point of operation when a sock is inserted, held, & withdrawn by hand

Question 10

Risk Reduction- Hierarchy of Control

Answer 10

1. Elimination of substitution
2. Engineering controls
3. Awareness Means
4. Training and Procedures
5. Personal Protective Equipment

Question 11

What are the 4 different types of safeguards?

Answer 11

• fixed guard
• interlock guards
• interlock grands
• adjustable guard

Question 12

What are safeguards?

Answer 12

“Barriers that prevent entry into the point of operation or other hazard area” -ANSI

Question 13

What are fixed guards?

Answer 13

Prevent and/or control access to hazard areas
· Around, under, through, over (AUTO)
· Selection of material
· safe distance
· color

-gotcha stick

Question 14

What is a gotcha stick? (fixed guards)

Answer 14

A gotcha stick measures the allowable barrier opening size based on distance from the point of operation

Question 15

What are interlocked guards?

Answer 15

· shuts off or disengages power and prevents starting of the machine when the guard is open

· Should require the machine to be stopped before the worker can reach into the danger area

Question 16

What is the issue with interlocked guards?

Answer 16

The problem with this guard is the safety feature can be bypassed by ‘fake’ closing guard with screw driver

Question 17

What are adjustable guards?

Answer 17

Provides a barrier which may be adjusted to facilitate a variety of production appearances

ex: blade guard

Question 18

What are 6 general requirements for safeguards?

Answer 18

1. Remain secure
2. Create no new hazards
3. Allow safe lubrication
4. create no interference
5. Protect from falling objects
6. Prevent contact

Question 19

What are some point-of-operation devices? (POD)

Answer 19

· photoelectric
· Radio frequency
· electromechanical · pullback
. restraint
. Safety trip
· two-hand controls

*there are others

Question 20

What is a photoelectric (optical presence, sensing) POD?

Answer 20

Photoelectric devices are optical devices that shut down the machine whenever the light field is broken

Question 21

What are the limitations with Photoelectric (optical presence, sensing) POD devices?

Answer 21

· Do not protect against mechanical failure
· Require frequent calibration
· can be used only with machines that can be stopped
· Do not protect workers from parts that may fly out of the point of operation area
· Only used on machines that can be stopped before a worker can reach the danger area

Question 22

What is blanked related to photoelectric devices and other devices?

Answer 22

· Means bypassing a portion of the sensing field of a presence-sensing device

· Different types of blanking are available for different types of operations

Question 23

What is enabling devices?

Answer 23

-Provides the margin of safety during troubleshooting, set up programming or servicing, or robotic, or automated machinery, with no other safeguarding means, are possible or practical

-Test have shown that human reaction to an emergency may be to release an object or to hold on tighter

-Not a substitute for a guard

Question 24

What are pull back devices (POD)?

Answer 24

-Pull the operator’s hands out of the danger zone when the machine starts to cycle

-They limit operator movement, must be adjusted for each individual operator and require close supervision

Question 25

What are restraint devices? (POD)

Answer 25

-Hold the operator back from the danger zone- with little risk of mechanical failure -They also limit the operator movement, must be adjusted for each individual operator, and require close supervision. -can only reach so fast so hands don’t get injured by equipment

Question 26

What are safety trip devices? (POD)

Answer 26

-Safety trip devices include tripwires, trip rods, and body bars, which stops the machine went tripped. -Devices located around the perimeter of or near the danger area -Operator must be able to reach the cable to stop the machine

Question 27

What are two hand controls? (POD)

Answer 27

-Require the operator to use both hands concurrently to activate -Ensures that hands cannot strain the danger zone -Some can be tampered with and made operable using only one hand

Question 28

What are safety floor mats? (POD)

Answer 28

-Pressure sensitive electric switches (shuts equipment down) -A stop signal is initiated when an object is sensed in the danger area

Question 29

What is distance in relation to POD?

Answer 29

-Makes it impossible to contact moving parts -Separates operators from the equipment -Limited by the available workspace

Question 30

What are issues with safety floor mats? (POD)

Answer 30

-Can step over -Expensive -easily damaged by things that fall on the floor -Surface beneath must be flat, (if not short it out)

Question 31

What are the hazards associated with robot safeguards?

Answer 31

-entrapment of worker between a robot and solid surface -Impact with a moving robot arm -Impact with objects ejected or dropped by the robot

Question 32

What is the best safety option for robot safeguards?

Answer 32

-a physical barrier around the entire perimeter of a robots work envelope (best option) -various types of shutdown guards can also be used

Question 33

What are sone facts/rules about emergency stops?

Answer 33

· shall remain unguarded · shall be prominent & accessible from all operator position · colored red · suitably marked · Require manual reset before restarting · Not to be used for normal stopping · Not to be relied upon for isolation · Not an alternative to guarding

Question 34

What do you do when conducting periodic audits?

Answer 34

· Compare with previous assessment report · machine location or uses may have charged · Location and proper use of guards · Modify guarding (if needed) to accommodate process or usage changes · check machines made prior to 1971 · check machines made overseas (ISO)

Question 35

What is abrasive wheel machinery? (1910.215)

Answer 35

· Commonly used machinery · Guarding of abrasive wheel · Mounting

Question 36

What are safety precautions when using abrasive

Answer 36

- eye shields vs goggles -loose clothes/accessories -Work rest -tongue guard -"Ring test” by tapping a chel with the nonmetallic handle of a screwdriver

Question 37

What is the ring test for abrasive wheels?

Answer 37

-All abrasive wheels must be closely inspected and ring tested. -you tap and listen for ring tone

Question 38

What is the gist of mechanizal hazards?

Answer 38

Where there is a risk of exposure to dangerous parts during: · operation · examinative · lubrication · adjustment · maintenance that risk must be eliminated, or, where it cannot be eliminated, minimized