Engineering Controls for Silica in Construction – Concrete Grinder. Concrete polisher grinder
Engineering Controls for Silica in Construction – Concrete Grinder
Construction workers who perform concrete grinding may breathe dust that contains respirable crystalline silica (RCS). A NIOSH [1] pdf icon study found that workers grinding concrete to smooth poured concrete surfaces were exposed to high levels of dust containing RCS, ranging from 35 to 55 times the NIOSH recommended exposure limit (REL). The Concrete Grinder without Engineering Controls video shows a worker performing a task with a concrete grinder while the overlay shows consistently high levels of respirable dust in the air.
Local exhaust ventilation systems (LEV) can be attached to concrete grinders to reduce RCS exposures. Researchers have found that levels of exposure to RCS were significantly lower when workers used a grinder equipped with an LEV system compared to a grinder used without LEV.
An LEV system consists of a grinder equipped with a ventilation shroud, a length of flexible hose, and a portable electric vacuum cleaner that acts as the fan and dust collector for the ventilation system. Some specifications for an LEV system for a concrete grinder are listed below.
Vacuum Cleaner
The vacuum should have the following features:
- Sufficient flow rate to capture the dust and transport it to the vacuum source.
- A high-efficiency particulate air (HEPA) filter to reduce the chances of releasing dust containing RCS from the vacuum into the worksite.
- A pre-filter or cyclone to increase the length of service of the HEPA filter.
- A filter replacement indicator.
- The ability to clean and replace filters and full collection bowls or bags without exposing the operators to dust.
- A motor that draws at least 10 amps.
Hose
The hose should have a diameter of 1.5- or 2-inches with a relatively smooth interior and a length of no more than 15 feet to provide adequate air flow.
Shroud
The type of shroud to be used depends on the preferences of the cement finisher and the employer, according to the task to be performed.After testing different types of shrouds, NIOSH determined that all were equally effective, reducing dust exposure by at least 90%.
The Concrete Grinder with Engineering Controls video shows a worker using a concrete grinder with a LEV system. The left bar of the graphic overlay of the video shows low amounts of respirable dust when compared to the initial video (above).
Dust controls in the form of local exhaust ventilation (LEV) systems offer several benefits. Those benefits include reducing worker exposure to hazardous dust, potentially allowing for use of less protective respiratory protection; reduced cleanup time; and reduced exposures during cleanup. The LEV dust control may greatly reduce worker exposures to hazardous dust. However, respirators are still necessary to reduce exposure to RCS below the NIOSH REL of 50µg/m 3.
Additional Information
For more information about dust controls for concrete grinders see:
- In-depth survey report of four sites: exposure to silica from hand tools in construction chipping, grinding, and hand demolition at Frank Messer and Sons Construction Company, Lexington and Newport KY; Columbus and Springfield, OH. NIOSH Report No. EPHB 247–15 (2001).
- Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding. [PDF – 280.05 KB] external iconJournal of Occupational and Environmental Hygiene:2010/ 7: 700-711.
- Crystalline silica dust and respirable particulate matter during indoor concrete grinding, wet grinding and ventilated grinding compared with uncontrolled conventional grinding. [PDF – 1.58 MB] external iconJournal of Occupational Environmental Hygiene: 2007 / 4:770–779.
- Protecting tuckpointing workers from silica dust: draft recommendations for a ventilated grinder. external iconThe Center to Protect Workers’ Rights, Silver Spring, MD (2005).
- The efficacy of local exhaust ventilation for controlling dust exposures during concrete surface grinding. pdf icon [PDF – 186.91 KB] external iconAnnals of Occupational Hygiene: 2004 / 48(6):509–518.
- Control of silica exposure from hand tools in construction: grinding concrete. [PDF – 341.43 KB] external iconApplied Occupational Environmental Hygiene: 2002 / 17(7):457–461.
- Respirable crystalline silica dust exposure during concrete finishing (grinding) using hand-held grinders in the construction industry. [PDF – 41.57 KB] external iconAnnals of Occupational Hygiene: 2002/ 46(3):341-346.
- Hazard Review: Health effects of occupational exposure to respirable crystalline silica.NIOSH Publication No. 2002–129.
- In-depth survey report of control of respirable dust and crystalline silica from grinding concrete at Messer Construction, Newport, Kentucky and Baker Concrete Construction, Dayton, Ohio [PDF – 331.84 KB]. pdf iconNIOSH Report No. EPHB 247–21 (2002).
- Alert: Request for assistance in preventing silicosis and deaths in construction workers. NIOSH Publication No. 96–112.
- Control of Hazardous Dust When Grinding ConcreteDHHS (NIOSH) Publication Number 2009-115
- Control del polvo peligroso que se genera durante el pulido de concretoDHHS (NIOSH) publicación N.º 2009-115
Floor Grinder
Powered by only 110 V or 230 V single phase our grinder reaches the class of 3 phase machines with the weight of only 43 kg !
- Of course dust free due to an integrated dust port
- Handle bar removable and adjustable for height
- Within seconds small enough for a car boot
- Removable dust shroud
- Grinds up to the wall
- Replaceable diamond segments
- Flexible coupling
- Various Tools
ALPHA-S
The proven “ALPHA” grinder also available with the speed control.
OMEGA-230
The universal machine for concrete, asphalt, wood, steel and formwork. Outstandingly versatile, the OMEGA performs many different operations. OMEGA combines impressive high performance with low weight. Even grinding concrete is no problem. The simple design of the OMEGA ensures easy operation. The handlebar can be quickly adjusted for operator comfort and control. Noise and vibration levels are minimal during normal operation. The compact dimensions and low weight of the OMEGA llow it to pass through all doors and be transported to every floor level, even onto a balcony. Edging work need no longer be completed using an angle grinder. The OMEGA can grind within a few millimeters of a wall. Operating the OMEGA with a suitable vacuum unit ensures dust free operation.
- 230 V, 1 Phase motor
- Grinding of concrete, steel, asphalt and wood
- Removal of paint and coatings
- Edging work in buildings
- Cleaning and maintenance of formwork
- Cleaning of floors
- Preparation of concrete
OMEGA-400
The universal machine for concrete, asphalt, wood, steel and formwork. Outstandingly versatile, the OMEGA performs many different operations. OMEGA combines impressive high performance with low weight. Even grinding concrete is no problem. The simple design of the OMEGA ensures easy operation. The handlebar can be quickly adjusted for operator comfort and control. Noise and vibration levels are minimal during normal operation. The compact dimensions and low weight of the OMEGA llow it to pass through all doors and be transported to every floor level, even onto a balcony. Edging work need no longer be completed using an angle grinder. The OMEGA can grind within a few millimeters of a wall. Operating the OMEGA with a suitable vacuum unit ensures dust free operation.
- 400 V, 3 Phase motor
- Grinding of concrete, steel, asphalt and wood
- Removal of paint and coatings
- Edging work in buildings
- Cleaning and maintenance of formwork
- Cleaning of floors
- Preparation of concrete
OMEGA P
The proven OMEGA P power grinder with gasoline engine. Ideal for construction sites without electricity.
The wide range of grinding tools makes the OMEGA P grinders extremely versatile Superb results on most types of floors, including concrete, terazzo and asphalt.
The universal machine for concrete, asphalt, wood, steel and formwork. Outstandingly versatile, the OMEGA P performs many different operations. OMEGA P combines impressive high performance with low weight. Even grinding concrete is no problem. The simple design of the OMEGA P ensures easy operation.
The handlebar can be quickly adjusted for operator comfort and control. Noise and vibration levels are minimal during normal operation. The compact dimensions and low weight of the OMEGA P allow it to pass through all doors and be transported to every floor level, even onto a balcony. Edging work need no longer be completed using an angle grinder. The OMEGA can grind within a few millimeters of a wall. Operating the OMEGA P with a suitable vacuum unit ensures dust free operation.
- Grinding concrete, steel, asphalt and wood
- Removal of paints, coatings and adhesives
- Edging of building surfaces
- Cleaning and maintenance of formwork
- Roughening of concrete floors and screeds
- Cleaning of floors
OMEGA 450 /h2>
The “All-Rounder” of the CONTEC Grinders and one of the most powerful grinders according to its weight. The new shaped disc with a diameter of 450 mm gives the OMEGA 450 an enormous cutting speed and an unprecedented grinding performance!
Thanks to the unique speed control from 0 to 1500 r.p.m. The OMEGA 450 feels at home on all kinds of different floors. from aggressive grinding of concrete, screeds and asphalt to the electronic “soft-start” for gentle polishing of design screeds, natural stone and terrazzo. The various tools available ensure easy removal of coatings, adhesives and paint residues and hard sinter layers.
DELTA II
The most advanced two speed grinders available. The wide range of grinding tools and operating options make the DELTA II grinders extremely versatile. They can grind most types of floors including concrete, terazzo and asphalt. The DELTA II grinders are ideal for surface preparation prior to the application of epoxy and similar coatings. They will effectively remove rubber deposits, adhesives, bituminous coatings and impacted dirt from factory floors. The DELTA II grinders are incredibly easy to operate and can be used with an industrial vacuum for a dust free working environment. Vibration and noise levels have been reduced to a minimum for the operator’s safety and convenience. The unique triangular shape of the grinding tools increases the performance and the overlap created helps prevent the “rings” normally associated with twin headed grinders. With no gap between the discs it is now possible to walk forward with the machine. The finish achieved with DELTA II grinders is extremely fine and swirl free, requiring only a minimum of coating to cover.
DELTA II-S
The DELTA II-S is the same as DELTA II but has one constant speed.
- The most advanced two speed grinders available.
- Wide range of grinding Tools make the DELTA II and DELTA II-S grinders extremely versatile
- Grind most types of floors including concrete, terazzo and asphalt.
- DELTA II grinders are ideal for surface preparation prior to the application of epoxy and similar coatings.
- Effectively remove rubber deposits, adhesives, bituminous coatings and impacted dirt from factory floors.
- DELTA II grinders are incredibly easy to operate and can be used with an industrial vacuum for a dust free working environment.
- Vibration and noise levels have been reduced to a minimum for the operator’s safety and convenience.
- The unique triangular shape of the grinding tools increases the performance and the overlap created helps prevent the “rings” normally associated with twin headed grinders. With no gap between the discs it is now possible to walk forward with the machine.
- The finish achieved with DELTA II grinders is extremely fine and swirl free, requiring only a minimum of coating to cover.
DELTA II-P
The proven power Grinder DELTA II with gazoline engine. Ideal for construction sites without power supply.
The most advanced two speed grinders available.
- Wide range of grinding Tools make the DELTA II grinders extremely versatile
- Grind most types of floors including concrete, terazzo and asphalt.
- DELTA II grinders are ideal for surface preparation prior to the application of epoxy and similar coatings.
- Effectively remove rubber deposits, adhesives, bituminous coatings and impacted dirt from factory floors.
- DELTA II grinders are incredibly easy to operate and can be used with an industrial vacuum for a dust free working environment.
- Vibration and noise levels have been reduced to a minimum for the operator’s safety and convenience.
- The unique triangular shape of the grinding tools increases the performance and the overlap created helps prevent the “rings” normally associated with twin headed grinders. With no gap between the discs it is now possible to walk forward with the machine.
- The finish achieved with DELTA II grinders is extremely fine and swirl free, requiring only a minimum of coating to cover.
ORBITER 450
ORBITER 450 is perfect for grinding and smoothing old, painted and damaged wood flooring as well as new ones, and works equally well when grinding plank flooring and parquet floors.
ORBITER 450 thanks to its size, is a very smooth machine that easily grinds close up to the wall. The adjustable speed allows you to adjust your speed according to the type of surface when grinding. Adjustable speed is often crucial when sanding wooden floors.
There are a large number of tools and sandpapers in different grits that can easily be mounted on the machine with velcro holders or our custom made discs.
The discs enable easy and quick handling when changing or assembling tools. With a simple touch the tools are fitted in custom cuts and with a light push they are in place.
For smooth and simple transport the ORBITER 450 is easy to separate into two parts.
ORBITER 500 i
ORBITER 500 i is a highly effective and powerful machine in contrary to its compact size. The machine has a high reliability and it is easy to get started with and simple to operate and maneuver.
It is a robust and strong machine for use when grinding concrete and stone. You can also use it for renovating, removing coatings and remove impurities from the surface.
For the ORBITER 500 i there is a large variety of grind-, polish-, scratch tools and sandpapers for different surfaces and conditions.
The ORBITER 500 i features 100% steel construction, along with our patented flex head system for reduced vibration and smooth operation on rough surfaces.
This construction gives a reliable machine with minimal maintenance.
ORBITER 500 PD
A new range of grinding machines. The ORBITER 500 PD is an efficient, strong machine for use when grinding concrete, stone and terrazzo. ORBITER 500 PD comes with a built-in water tank for wet grinding. This takes away the problem with external water supply. Superb handling in renovating, removing coatings and remove impurities from the surface.
ORBITER 500 PD has a large variety of grinding, polishing and scratching tools sandpapers for different surfaces and conditions. ORBITER 500 PD is made of 100% steel construction, along with our ‘Flex-Head’ system for reduced vibration and smooth operation on rough surfaces. ORBITER 500 PD. a superbly reliable machine with minimal maintenance. ORBITER 500 PD. equipped with adjustable speed, this makes the machine work very well on all types of surfaces, such as concrete, stone and terrazzo.
Optional extra weight available.
ORBITER 650
The ORBITER 650 is a robust and stable machine made of steel, designed for both residential and commercial projects with its grinding width of 650mm. The ORBITER 650 uses a patented planetary system to drive its three heads. This patented system uses a double-sided cog belt. The components are carefully chosen to ensure a safe dependable operation and high quality
ORBITER 650 is extremely durable and easy to maintain. The design helps to reduce the torque and stress on the operator. With the ORBITER 650 there is also the option for wet grinding by using the simple water connection.
Mechanical Concrete Preparation. Profiling With a Grinder
ORBITER 800
The ORBITER 800 contra rotating floor grinder was designed with a FOCUS on the operator. This is demonstrated by the ergonomic handle design, ease of use, and advanced features that provide real time feedback to the operator. The machine features cast alloy components along with a floating shroud, designed for years of durability and dust free operation. The ORBITER 800 is equipped with a new toolhead for better balance and tool support and a new electrical cabinet with an improved cooling system that is sealed which protects the electrical components from heat and dust. The 370 mm wheels and the quick release makes it easy to operate and maneuver the machine manually.
From allowing the operator to be more productive on the job site to reduced down time for repairs and maintenance, The ORBITER 800 will help your business run faster – this is grinding in the fast lane for real.
The ORBITER 800 is also available in RC – remote controlled.
Grinders and Polishers
We have a wide range of concrete, floor grinders, floor polishers and floor grinder rentals. We rent, and service the best machines on the market. Our experienced sales staff and personnel can help you pick the right grinder or polisher for you job. We also offer hand grinders designed to make you job easier including Metabo, Bosch, Makita brands plus many more angle grinders, sander and polishers.
MultiQuip WHITEMAN Polishing TROWEL HYDROSTATIC RIDER
STX6H 10ft. Retrofitted with Revolution Rotary System ride-on trowel for polishing. This original and unique retrofit design will allow teams to cut polishing time dramatically. 70-HP Hatz tier turbo diesel Revolution Rotary pad system for maximum efficiency

DIAMATIC-1727 PROPANE BURNISHES-27 INCH Polisher
30/40-60/80 METALS RASINS The new BMG-535PRO-R is an ideal machine for preparing surfaces prior to new coatings. Perfect for to smoothing or flattening concrete slabs including curled expansion joints, or to just simply remove unsightly surface imperfections.
For decorative concrete applications, it is an ideal system for polishing concrete to a high shine or restoring old slabs for newer architectural finishes.
DIAMATIC – 1330 VACUUM DBP DUST COLLECTOR SYSTEM
The Diamatic BDC-1330 has been designed for the tough conditions of concrete dust collection and built for multi-purpose use,from hand grinders and crack chasers, to small and medium grinding and polishing machines. Its superior filter system reduces airborne dust and particulate to provide a cleaner work environment.

Diamatic – Single Phase 535 ProR Planetary Grinder / Polisher
30/40-60/80 METALS RASINS The new BMG-535PRO-R is an ideal machine for preparing surfaces prior to new coatings. Perfect for to smoothing or flattening concrete slabs including curled expansion joints, or to just simply remove unsightly surface imperfections.
For decorative concrete applications, it is an ideal system for polishing concrete to a high shine or restoring old slabs for newer architectural finishes.
Diamatic – Single Phase 535 ProR Planetary Grinder / Polisher
The new BMG-535PRO-R is an ideal machine for preparing surfaces prior to new coatings. Perfect for to smoothing or flattening concrete slabs including curled expansion joints, or to just simply remove unsightly surface imperfections.
For decorative concrete applications, it is an ideal system for polishing concrete to a high shine or restoring old slabs for newer architectural finishes.
HW-G8 CONCRETE GRINDER POLISHER
Planetary counter rotation for excellent grinding surfaces.
Special design of disc available for different kinds of abrasive.
Well designed sealing system for gear box.
Recommended dust extractor: SP-D3.
Understanding Silica In Construction
Recommended generator: 33kw.
HW-G8 220V 380V CONCRETE GRINDER POLISHER
30 inches grinding width with 748lbs is suited for large size floor surfaces. It is mostly applied in three phrase; IP67 industrial plugs are waterproof and dust proof. Planet disc plates rotate conversely, creating a finer, denser, and more exquisite floor.
Honway gears are made by world top gear processing equipment Reishauer which guarantees that the gears are made solid, still keeps flexibility, but not elastic. Gears’ accuracy and solidity make sure that gears drives precise like a Rolex watch.
HW-G8 concrete grinder polisher is large size among the planetary gear structure series, the grinding width 750mm with 3 pieces of grinding disc, 15hp motor, 18.5hp inverter (220V), variable motor speed 300-1800rpm.
Compared to non planetary concrete grinder, the planetary grinder is more powerful and effective, maximizing overall production hours and minimizing maintenance time.
APPLICATION
Removing surface imperfections and contaminants.
Provides ideal preparation for thin film coating.
Grinding and Polishing Concrete, Terrazzo, natural and artificial stone.
TECHNICAL SPECIFICATION
Model | HW-G8A | HW-G8B |
Voltage | 380-440 V 3~ | 220-240 V 1~ |
Motorpower | 11kw(15hp) | 11kw(15hp) |
Frequency | 50/60HZ | 50/60HZ |
Inverter | 11kw(15hp) | 15kw(20hp) |
Current | 22A | 39A |
Grinding disc speed | 0-900rpm | 0-900rpm |
Grinding disc | 3×250 mm / 3×10″ | 3×250 mm / 3×10″ |
Grinding width | 650mm(25.5″) | 650mm(25.5″) |
No.of diamond | 9pcs | 9pcs |
Extra weight | 25kg(55lbs) | 25kg(55lbs) |
Water tank | 20L | 20L |
Weight | 340kg(748lbs) | 340kg(748lbs) |
LWH | 10007501050mm | 10007501050mm |
ADVANTAGES
Forward and reverse switch: change the motor direction has two benefits: to prevent uneven wear of the grinding disc and achieve a smoother floor finish.
Precise and strong gearbox: allows the machine on any rough surface without worry about belt loose.
Polyurethane rear wheels: heavy duty, for affords over 1000kg weight
Double oil seal: one is inside and one is outside the gear box, easy to replace, no need to open the gear box
Easy to maintain: all spare parts are assembled like building block. It is easy to enter into the machine heart.
Brand electrical parts: all electrical parts, including the buttons and cable, all from brand manufacturer, with CE and VDE certs.
Q: DOES YOUR FACTORY ACCEPT CUSTOM-MADE?
A: Yes, we can provide OEM and ODM service to customer. Including different color, motor, inverter etc. We also can mark your own logo and brand on the machine. You just need send us the drawing or sample, we will produce the according to them. And we will not sell this kind of products to other customers only if we get your permission.
Q: HOW TO KNOW YOUR MACHINES’ QUALITY BEFORE WE ORDER THE PRODUCT?
A: Firstly, we have the manufacture base of our own, CNC manufacture processing and QC check procedures. and more people in the world to use Chinese brand product because of the high quality and very good competitive price. we are specialized in producing floor grinding machines since 2006.
Secondly, we have sold our products to 100 countries around the world, we are developing and expanding distributors around the world, and also you can visit our factory at any time.
Thirdly, the warranty of motor, inverter and other main parts are ONE year.
We promise to help maintenance our machine forever. If exceed guarantee time, spare parts broken due to long time using, we will always have the spare parts in stock, you just need pay the cost price and Express fee of the parts, and we will send you steps or video to help you repair. Our after-sale service is open to you at any time, even during our holidays.
All in all, we welcome sample orders or come visit our factory to test the quality.
Q:WHAT SHALL I DO TO START CONCRETE FLOOR POLISH?
A: We recommend using a complete surface treatment system including: concrete grinder polisher machines, industrial vacuum cleaners (dustless)with Hepa filters, diamond tools, chemicals (thickeners, sealants, dyes-optional).
Of course it is also important to receive proper training to ensure that your project is completed in a professional, timely and cost-effective manner.
Q: ARE YOU REAL MANUFACTURER ?HOW CAN I VISIT YOUR FACTORY?
A: Yes of course, we are the manufacturer! We warmly welcome clients to visit our factory to inspect our factory at any time. Our factory is located in Changsha city (Well known Capital of Construction Machinery in China).