Abrasive Wheels Training Certificate Angle Grinder Safety & PPE — Questions and Answers
Question 1: What PPE is mandatory when using an angle grinder?
- Safety goggles or face shield, hearing protection, dust/fume RPE (minimum FFP2), leather or cut-resistant gloves, and safety footwear; high-visibility clothing if near traffic (Correct answer)
- Safety spectacles only — goggles are not required for brief grinding tasks
- Hearing protection only — eye protection is optional if the guard is in place
- RPE is only required when grinding stainless steel
Correct answer: Safety goggles or face shield, hearing protection, dust/fume RPE (minimum FFP2), leather or cut-resistant gloves, and safety footwear; high-visibility clothing if near traffic
Angle grinder PPE must address all identified hazards: face shield or safety goggles (eye/face injury from sparks and fragments), hearing protection (95–110 dB(A)), RPE appropriate to the material being ground (minimum FFP2, P3 for toxic dusts), cut-resistant gloves, safety footwear. The guard does not eliminate the need for eye protection.
Question 2: Why should leather gloves be worn rather than standard work gloves when using an angle grinder?
- Leather provides protection against hot sparks, abrasion from the disc if accidental contact occurs, and vibration transmission reduction; synthetic gloves can be grabbed by the disc and drawn in (Correct answer)
- Cotton gloves are safer than leather as they do not conduct heat
- Gloves of any type are not recommended as they reduce dexterity
- Rubber gloves provide the best electrical insulation when using electrical power tools
Correct answer: Leather provides protection against hot sparks, abrasion from the disc if accidental contact occurs, and vibration transmission reduction; synthetic gloves can be grabbed by the disc and drawn in
Leather gloves resist hot sparks without melting onto the skin, provide some abrasion resistance if the disc contacts the hand (though cannot prevent serious injury), and slightly attenuate vibration. Synthetic or fabric gloves can melt from sparks or be caught by the disc, potentially drawing the hand into the grinding surface.
Question 3: What is 'kickback' on an angle grinder and how does it occur?
- Sudden violent rotation of the grinder opposite to the disc rotation direction when the disc binds, catches, or pinches in the workpiece — caused by cutting through thin sections or using worn discs (Correct answer)
- A slow backwards movement of the grinder when pressure is released
- A vibration pattern caused by an unbalanced disc
- A safety feature that stops the disc when excessive pressure is applied
Correct answer: Sudden violent rotation of the grinder opposite to the disc rotation direction when the disc binds, catches, or pinches in the workpiece — caused by cutting through thin sections or using worn discs
Kickback occurs when the grinding disc suddenly stops rotating due to pinching, binding, or catching in the workpiece. The disc's stored kinetic energy is violently transferred to the machine body, rotating it rapidly in the opposite direction (counter-rotation). The resulting sudden movement can cause severe hand, arm, or head injury.
Question 4: What is the safe technique for cutting with a thin cut-off disc to avoid disc breakage?
- Apply light, steady pressure; never twist or lever the disc sideways; allow the disc to cut freely in a straight line; use two hands on the machine (Correct answer)
- Press firmly into the cut to minimise the cutting time
- Rock the disc slightly from side to side to clear the cut
- Allow the disc to do the work by holding the grinder with one hand only
Correct answer: Apply light, steady pressure; never twist or lever the disc sideways; allow the disc to cut freely in a straight line; use two hands on the machine
Cut-off discs must only experience forces in the plane of rotation (forward cutting pressure). Any twisting, rocking, or lateral force causes flexural stress for which thin discs have almost no tolerance. The disc will crack and burst. Two-handed control, light steady pressure, and a straight cut line are the key technique points.
Question 5: What respiratory protective equipment (RPE) face piece is required when dry grinding stainless steel?
- A minimum of FFP3 disposable respirator or half-face P3 respirator, as stainless steel grinding produces hexavalent chromium — a confirmed carcinogen (Correct answer)
- FFP1 disposable is sufficient for all metalworking operations
- RPE is not required if local exhaust ventilation is provided
- A full-face air-purifying respirator with A2 organic vapour filter
Correct answer: A minimum of FFP3 disposable respirator or half-face P3 respirator, as stainless steel grinding produces hexavalent chromium — a confirmed carcinogen
Grinding stainless steel generates hexavalent chromium (Cr(VI)) fume — a Group 1 carcinogen with a very low WEL of 0.01 mg/m³. FFP3 or P3 filter class provides the highest particle filtration efficiency (>99%). LEV alone may not be sufficient in some positions, making high-efficiency RPE essential as an additional control.
Question 6: What is the safe procedure when an angle grinder disc jams or stalls during cutting?
- Release the trigger immediately, hold the machine firmly until the disc fully stops, then withdraw the stopped disc from the cut before investigating the jam (Correct answer)
- Increase motor power by pressing harder to free the jam
- Quickly twist the grinder sideways to free the disc
- Switch off and immediately pull the disc backwards out of the cut while it is still rotating
Correct answer: Release the trigger immediately, hold the machine firmly until the disc fully stops, then withdraw the stopped disc from the cut before investigating the jam
If the disc stalls: release the trigger, keep both hands on the machine to control any kickback, and hold the machine steady until the disc completely stops. Only then withdraw the disc from the cut. Pulling a spinning disc backwards out of a jam causes lateral forces that can snap the disc; twisting causes immediate breakage.
Abrasive Wheels Training Certificate Angle Grinder Safety & PPE
What PPE is mandatory when using an angle grinder?