Concrete construction frequently requires cutting into cured concrete. This is a specialised job that requires quality equipment and well-trained workers. As with many skills in the construction industry, concrete cutting has a lot of specialised safety considerations. Here’s a brief overview:
How concrete gets cut?
Concrete cutting is a significant part of construction work in both commercial and residential applications. It’s also commonly required in civil engineering projects and road work.
Cutting concrete is a job for heavy-duty power tools. Hand-held concrete cut-off saws exist, but the most common tool for significant cutting jobs is a walk-behind saw. Today, most concrete saws use diamond blades, although abrasive wheels are a less-common option.
Concrete sawing can be done either “dry” or “wet,” with wet sawing making up the majority of the work. Water helps to cool the saw blade and reduces the impact of dust created by cutting (see below).
Basics About Equipment
Matching the cutting gear to the job is extremely important if work is to be done safely and efficiently. Manufacturer’s recommendations provided by both the makers of the saw and the makers of the blade should be followed at all times.
Different blades are made for different materials, and also for different cutting depths. The composition of the concrete to be cut – aggregate fill, reinforcement, and density – must be ascertained before picking the right blade to do the job. As covered in greater depth below, it’s important to ensure that the saw’s blade is in good working order before starting to cut. This is a skill that’s essential for any trained concrete cutter.
Appropriate clothing must be worn by all workers using a concrete saw. Exposed skin must be avoided if at all possible. Eye protection is a must, as is hearing protection. (Concrete saws are extremely noisy while operating.) For road work, a high-visibility vest is an essential part of the concrete cutter’s working outfit. As with all power tools, concrete saws should only be operated in properly-posted environments with adequate first aid supplies within easy access.
Every concrete saw has a full start-up checklist to run through prior to cutting. It’s important for concrete cutters to be thoroughly familiar with the exact equipment they’re using and to make each appropriate check before starting operations.
For all concrete saws, verifying the condition of the diamond blade is a must. Cutters must check for any cracks, missing blade segments or other signs of wear and remove blades that are in any way damaged. Experienced cutters also know how to look for signs of discoloration (commonly blue-black) that can indicate heat stress and a possibly weakened blade.
Patience and certainty are very valuable traits for concrete cutters. Despite their amazing cutting power, diamond saw blades are surprisingly fragile. Forcing them beyond their normal operating conditions can easily result in damage or injury.
In most concrete cutting jobs, cuts should be laid out with a string or chalk line in advance and lined out for the cutter with a clearly-visible wooden board. It should be easy for him to follow a straight line in order to minimise blade wear due to twisting and turning.
“Pilot” cuts are frequently employed to make concrete cutting easier; these are shallow (usually quarter-inch) cuts laid out at the start of a job to identify where deeper cuts are needed. When cutting begins in earnest, cutters will let the tool do the work. The blade should be allowed to settle to the proper cutting depth on its own and then moved at its own pace.
Aside from the threat of physical injury, the most important safety concern in concrete cutting is probably dust control. Most concrete contains plenty of crystalline silica, and the act of cutting it creates respirable crystalline silica, commonly known as RCS.
RCS is a severe irritant and can be so fine as to be almost invisible. Water-assisted concrete cutting reduces the production of dust but does not eliminate it. Most concrete saws except the smallest hand-held models have an on-board ventilation system to further reduce the creation of airborne RCS dust. Concrete cutters (both saw operators and assistants) should wear respirators at all times.
While concrete cutting is a complex, skilled job with a lot of potential dangers, it’s not hard for properly-trained cutters to stay safe while they work. As in many professions, a level-headed concrete cutter is one who always keeps safety in mind. With that mindful attitude, cutters can easily get their jobs done without putting themselves or their co-workers at risk.