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1. Angle Grinders
2. Angle Grinders Angle grinders, or side grinders, are handheld power tools that can be used for multiple purposes:
Cutting
Grinding
Polishing
3. Angle Grinders Discs are available for diverse uses:
Diamond and metal discs for cutting materials
Abrasive discs and stone wheels for grinding surfaces
Wire brush wheels and polishing pads for polishing surfaces
4. History The first hand held grinder, the M-6, was invented by Germans Hermann Ackermann and Hermann Schmitt in 1922.
In the late 1920s they created the first angle grinder.
In 1935 they began producing a low speed angle grinder and in 1954 they built a high speed angle grinder, known as the DL-9.
Today, angle grinders are produced by a myriad of firms, ranging from DeWalt to Norton.
5. Safety Concerns There are an abundance of hazards to consider when operating angle grinders.
Kick-back
The angle grinder may jump off of the
material it is being used on, possibly
causing lacerations to the individual
using it.
Disintegration
The disc may shatter while in
use, resulting in a flying hazard.
6. Safety Concerns (cont.) There are an abundance of hazards to consider when operating angle grinders.
Fire/Explosion
Sparks created by the grinder while in
operation can create a fire or explosion
if they come into contact with flammable
materials.
Electrical
Grinding surfaces that are charged or
coming into contact with power cords
can result in electrocution of the
individual using the grinder.
7. Safety Concerns (cont.) There are an abundance of hazards to consider when operating angle grinders.
Cuts & Abrasions
The grinding disc itself can cause
severe physical harm if it comes
into contact with the body.
Particulates
Dust and shavings from the work
surface can be cast into the air
while working with angle grinders.
These can cause problems ranging
from breathing issues to explosions.
8. Statistics Statistics were extracted from the OSHA Accident Investigation Data from 1990 to 2007.
There were 11 total fatalities involving angle grinders.
The causes are displayed in the following pie chart:
9. Statistics (cont.) Examples of incidents include:
Electrocution
Individual was killed when the surface he was hand grinding came into contact with a 7,200 volt power line.
Fall
Individual was using an angle grinder to remove an overhead pipe. The pipe fell when cut and knocked the individual off his stepladder. He died upon hitting the floor.
Fire/Explosion
Individual was grinding metal ductwork which contained sodium azide. This caused an explosion, killing the individual and hospitalizing six others.
10. Statistics (cont.) Examples of incidents include:
Laceration
Individual was using an angle grinder when the blade disintegrated and lodged in his neck, severing his carotid artery.
11. OSHA Regulations Subpart I Tools Hand and Power
CFR 1926.303: Abrasive Wheels and Tools
B. Guarding
1. Grinding machines shall be equipped with safety
guards.
C. Use of Abrasive Wheels
4. Portable abrasive wheels used for internal grinding shall be provided with safety flanges unless:
The wheels are 2 inches or less in diameter.
Wheels are entirely within the work being ground while in use.
12. OSHA (cont.) Subpart I Tools Hand and Power
CFR 1926.303: Abrasive Wheels and Tools
C. Use of Abrasive Wheels
7. All abrasive wheels shall be closely inspected and ring-tested to ensure that they are free from cracks or defects.
8.Grinding wheels shall fit freely on the spindle and shall not be forced on. The spindle nut shall be tightened only enough to hold the wheel in place.
9. All employees using abrasive wheels shall be protected by eye protection equipment.
13. Best Practices Proper P.P.E. to wear when operating an angle grinder includes:
Hard Hat
Face Shield
Gloves
Flame-resistant Clothing
Long-sleeve Shirt
Jeans
Boots
Hearing Protection
Knee Pads (if kneeling)
14. Best Practices (cont.) Consider a short checklist before beginning work:
Is grinding necessary?
Is an angle grinder the proper tool?
Is the correct disc being used for the task at hand?
Is the disc the proper size for the angle grinder?
Is the disc designed to operate at the grinders rotational speed?
Is the disc properly attached and secured?
Is the safety guard cover attached?
Is there a deadman switch on the grinder?
If the answer to any of these is no, do not use the grinder.
15. Best Practices (cont.) Other safe practices include:
Make sure other workers are a safe distance away.
Be sure there are no flammable materials nearby.
This includes the work surface itself as well as any gases or fumes.
Use two hands to operate the grinder.
Hold the grinder at a perpendicular angle to your body when using.
Check that the power cord and extension cord are properly sheathed and do not have exposed wires.
Make sure that the cord is routed so that the angle grinder cannot come into contact with it and so that it is not a hazard to other employees.
16. Best Practices (cont.) Other safe practices include:
Run up the grinder before applying it to the work surface.
Do not allow the grinder to bounce around or bump other surfaces.
Never place the grinder down until the disc has stopped rotating.
Remove the plug before changing discs out.
Disconnect the power and place the grinder face up when done.
17. Think Safety Work Safely