Sandblasting often called abrasive blasting, is a surface finishing method that uses a powered machine, typically an air compressor and a sandblasting machine, to spray abrasive particles against a surface at high pressure.
Sandblasting gets its name from the process itself, which involves blasting the surface with sand.
As the sand particles hit the surface, they make it smoother and more even. This article will educate you on the specifics of the surface finishing procedure.
An Introduction to Sandblasting
Sandblasting uses the abrasive/roughness properties of sand to make surfaces that are smoother and have fewer physical flaws. Sand is obviously rough and gritty.
These characteristics allow it to remove surplus or undesired material from a surface through wear and tear.
For instance, sandpaper actually does have granules of sand. If you rub sand across a surface, it will smooth it out by removing some of the surface layer.
The only difference is that sandblasting uses sand that has been subjected to extremely high pressure rather than water.
The sand is poured into the machine, which is the initial stage in sandblasting. The sand is put into the sandblasting machine’s chamber, which is located at the very top. The sandblasting equipment is hooked up to a regular air compressor, which, when turned on, forces the sand out through a portable nozzle. The sand’s pressure can range from 50 to 130 psi, depending on the conditions (PSI).
The abrasive qualities of the sand allow it to “blast” through the surface, leaving behind a smoother finish. Sandblasting is commonly used on concrete.
Sandblasting is done after the concrete has been set and dried. The procedure makes the concrete smoother by removing part of the surplus material on its surface.
What is the difference between sandblasting and shot blasting?
It is important to note that sandblasting is only one of many blasting-style surface finishing methods. Shot blasting is another option for reducing surface roughness and rigidity.
Which is more effective, sandblasting or shot blasting?
In sandblasting, a surface is bombarded with sand at high velocity.
However, tiny metal balls or beads are used to impact a target when using shot blasting. Metals, including stainless steel, copper, aluminum, and zinc, are frequently used to make balls or beads.
All these metals are tougher than sand; thus, shot blasting works better than sandblasting.
The Safe Use of Abrasive Blasting Materials in the Workplace
To clean an object or surface, remove burrs, apply a texture, or prepare it for painting or coating, abrasive blasting uses a high-velocity jet of an abrasive material propelled by compressed air or water.
Companies are responsible for safeguarding their employees from exposure to potentially harmful dust levels and toxic metals that may be generated by the blasting material, as well as the underlying substrate and coatings.
Information on abrasive blasting material, health risks, and worker protection measures are included in this fact sheet.
Materials for Abrasive Blasting
Considerations such as budget, task requirements, safety regulations, and worker health must be made before settling on an abrasive substance.
Typical examples of abrasive substances:
- Crystalline Silica Sand;
- Coal Slag; Garnet Sand;
- Nickel Slag Materials such as copper slag,
- glass (crushed or in beads),
- steel shot,
- steel grit,
- specular hematite can be used in this process (iron ore).
- Ice, dry ice,
- plastic bead media,
- sodium bicarbonate (baking soda),
- ground walnut shells,
- ground corn cob, and other biodegradable materials are some non-hazardous blasting options.
PLEASE TAKE PRECAUTIONS
Noise pollution from abrasive blasting can be so severe that it permanently impairs one’s hearing. Put on some earplugs at all times. The OSHA Occupational Noise regulation mandates that businesses have hearing protection policies.
Dangers to Public Health
Noise and dust can be significant byproducts of abrasive blasting. The surface may be blasted, and the abrasive material may contain harmful toxins like lead paint or silica. Crystalline silica sand has been linked to silicosis, lung cancer, and other respiratory disorders among employees exposed to it.
There is evidence that coal slag, garnet sand, and silica sand can damage a person’s lungs (based on preliminary animal testing). The lungs can also be damaged by copper slag, nickel slag, and glass (crushed or in beads).
There is a reduced risk of lung harm from steel grit and gunfire. Arsenic, beryllium, and cadmium are three examples of dangerous metals that may be present in slags in extremely low concentrations.
What Precautions Should Be Taken to Keep Workers Safe From Abrasive Blasting Materials?
Different surfaces, coatings, blast material, and working conditions make each abrasive blasting job one-of-a-kind.
Before starting work, companies should assess the risk involved and appoint someone familiar with the hazards who has the authority to address them promptly.
Protect personnel engaged in abrasive blasting by implementing engineering and administrative controls, issuing PPE (including respiratory protection), and providing training.
Engineering controls, such as substitution, isolation, containment, and ventilation, are the principal means of minimizing or lessening exposures to airborne dangers during abrasive blasting activities.
Good work and personal hygiene practices are examples of administrative measures that can help lessen exposure. Respiratory protection is required by OSHA when exposures to hazardous chemicals exceed the limits set by engineering and administrative controls.
Use a less hazardous abrasive blasting substance, and switch to abrasives that may be given with water (slurry) to cut down on dust.
Isolation and confinement
In order to protect other workers from blasting debris, erecting barriers and curtain walls is recommended. The use of blast rooms or blast cabinets should be made mandatory for all but the smallest of blasting operations. Keep coworkers away from the blaster and only use it in designated places when it is not enclosed.
make use of exhaust ventilation systems in dust-collecting containment buildings.
Regular wet cleaning or HEPA-filtered vacuuming should be performed to reduce the buildup of harmful dust. Compressed air cleaners are not recommended because they release dust into the environment. Decontaminate the location and clean any equipment that may have been contaminated, such as tarps.
Avoid blasting when winds are strong so that hazardous chemicals do not blow away from the site, and plan to blast for times when there are fewer workers present.
Maintenance of Proper Hygiene
Blasting sites should be dry zones where no food or drink is allowed, and smoking is strictly forbidden. Ensure employees have access to regular hand washing stations and are encouraged to use them before engaging in potentially hazardous activities like eating, drinking, or smoking.
Shower and changing facilities should be provided at the end of the shift, including space for street clothes and protective gear. Do not bring dirty gear into the clean changing room.
The wearer of an abrasive-blasting respirator must have full protection against the abrasive, including the head, neck, and shoulders. In order to protect themselves from the dust created during abrasive-blasting operations, employees must use only NIOSH-approved respirators.
Blasting aircraft respirator with positive pressure blasting helmet, certified to CE standards by NIOSH. Cleanup and other associated support staff duties may need the use of respirators.
Personal Protective Equipment
Protective clothing and gear include earplugs, goggles, a face mask, a hard helmet, leather gloves that cover the forearm, an apron, and safety boots.
Worker Training and Hazard Communication
• Educate abrasive blasters and support staff on the dangers of blasting, the best ways to prevent them, how to maintain personal cleanliness on the job and how to utilize protective gear such as respirators.
OSHA’s Hazard Communication standard mandates that manufacturers publish health hazard information on safety data sheets (SDS) for blasting materials (29 CFR 1910.1200).
• Get a copy of the Safety Data Sheet (SDS) from the abrasive blasting material’s manufacturer and read it thoroughly for information on potential health risks.
What is sand blasting? Sand blasting is the process of removing rust dust, dirt, scales, and old marks from an old surface by using high-pressure compressed air and very fine particles of an abrasive material like sand (which was commonly used in the past), steel grit, copper slits, powdered abrasives, etc.
Sandblasting is often done to get a surface ready to be painted. It is often used to remove paint from metal and machinery, but it also has many other uses.