Always call your local utility companies to make sure there aren't any underground utilities beneath the concrete. Hire a professional if there are. Digging above a utility line like gas or electric can be very dangerous. Concrete removal creates hazardous dust and sharp fragments, so protect yourself and your coworkers with safety goggles, dust masks or respirators, steel toe or other heavy boots, thick gloves, and thick clothing that covers your arms and legs. If you're going to be using power tools, especially a jackhammer, use ear protection. Be careful when using plastic sheets, as they can sometimes create a slipping or tripping hazard. However, sheeting can be worthwhile if you're breaking up concrete near fragile items or structures.  If you're breaking up concrete in a wide open area away from structures and other breakables, it's unlikely you'll need sheeting. Fragments of concrete can be launched great distances by the force of your hammer and tools. When in doubt, use a cover to protect the surrounding area. If you don't use plastic sheeting, protect any nearby windows and breakable objects with plywood sheets to protect the glass from concrete fragments. Whether you're using a sledgehammer or jackhammer, you'll likely need to pry apart the pieces of concrete as you break them apart. Concrete removal generally goes quickest if you have one person breaking apart the concrete and another following along and prying the pieces apart. If your concrete is 4 in (10 cm) thick or less, try using a sledgehammer. Start at any existing cracks or at a corner or edge, and keep in mind that thick concrete will be easiest to break closer to its outer edges.  Don’t try to swing the sledgehammer or lift it above your head; hold it at shoulder-height and let it fall onto the concrete, instead. Use the pry bar to pull apart the chunks of concrete after you break them apart. Then, move them out of the way to eliminate trip hazards. If after 10 minutes you've failed to make significant cracks or you are exhausted, you...

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Write a summary of the previous text in Vietnamese:
Gọi điện cho các công ty dịch vụ tiện ích. Sử dụng thiết bị an toàn. Sử dụng bạt nhựa phủ lên tấm bê tông để bảo vệ các vật dễ vỡ. Tìm một cây xà beng lớn. Sử dụng búa tạ để phá tấm bê tông mỏng. Đào bên dưới tấm sàn nếu bê tông quá cứng. Sử dụng máy đục bê tông. Xử lý lưới thép hay cốt thép trong bê tông. Sử dụng cuốc kéo rời các miếng bê tông bị kẹt.