Working Safely with  混凝土

混凝土 is easy to work with, versatile, durable, and economoicl. By taking a few basic precautions, it is also one of the safest building materials known.  Relatively few people involved in mixing, handling, and finishing concrete have experienced injury. 

Outlined below are some simple suggestions-protection, 预防, common sense precautions-useful to anyone working with portland 水泥 and concrete.  Workers should also consult the last information from the U.S. Department of Labor at www.osha.政府.

Protect Your Head and Eyes 

Construction equipment and tools represent constant potential hazards to busy construction  personnel. That's why hard hats are required on construction projects. It is therefore recommended that some sort of head protection, such as a hard hat or safety hat, be worn when working any construction job, 大或小.

Proper eye protection is essential when working with 水泥 or concrete. Eyes are particularly vulnerable to blowing dust, splattering concrete, and other foreign objects. On some jobs it may be advisable to wear full-cover goggles or safety glasses with side shields. Sight is precious. Protect the head and 眼睛 by using proper safety equipment and remaining alert.

Protect Your Back

man_diggingAll materials used to make concrete—portland 水泥, coarse aggregate, 沙子, and water—are quite heavy even in small quantities. When lifting heavy materials, your back should be straight, 腿弯曲, and the weight between your legs as close to the body as possible. Do not twist at the waist while lifting or carrying these items. Rather than straining your back with a heavy load, get help. Remember to use your head, not your back.

Let mechanical equipment work to your advantage by placing concrete as close as possible to its final position. After the concrete is deposited in the desired area by chute, 泵, 或手推车, it should be pushed—not lifted—into final position with a shovel. 一个short-handled, square-end shovel is an effective tool for spreading concrete, but special concrete rakes or come-alongs also can be used. Excessive horizontal movement of the concrete not only requires extra effort, but may also lead to segregation of the concrete ingredients.

Protect Your Skin

pouring_水泥When working with fresh concrete, care should be taken to avoid skin irritation or chemical burns. Prolonged contact between fresh concrete and skin surfaces, 眼睛, and clothing may result in burns that are quite severe, including third-degree burns. If irritation persists consult a physician. For deep burns or large affected skin areas, seek medical attention immediately.

The A-B-Cs of fresh concrete's effect on skin are: 

Abrasive Sand contained in fresh concrete is abrasive to bare skin.
Basic & portland 水泥 is alkaline in nature, so wet
Caustic concrete and other 水泥 mixtures are strongly basic (pH of 12 to 13). Strong bases-like strong acids-are harmful, or caustic to skin.
Drying portland 水泥 is hygroscopic-it absorbs water. In fact, portland 水泥 needs water to harden. It will draw water away from any material it contacts-including skin.

Clothing worn as protection from fresh concrete should not be allowed to become saturated with moisture from fresh concrete because saturated clothing can transmit alkaline or hygroscopic effects to the skin.

Waterproof gloves, a long-sleeved shirt, and long pants should be worn. If you must stand in fresh concrete while it is being placed, 冗长的, 或提出, wear rubber boots high enough to prevent concrete from getting into them.

The best way to avoid skin irritation is to wash frequently with pH neutral soap and clean water.

Placing and Finishing

Waterproof pads should be used between fresh concrete surfaces and knees, elbows, hands, etc., to protect the body during finishing operations. Eyes and skin that come in contact with fresh concrete should be flushed thoroughly with clean water. Clothing that becomes saturated from contact with fresh concrete should be rinsed out promptly with clear water to prevent continued contact with skin surfaces. For persistent or severe discomfort, consult a physician.

Additional Information

For a complete listing of publications, 录像带, and further information on concrete safety for contractors, contact the American Society for 混凝土 Construction (ASCC) at 1.800.877.2753, or 38800 Country Club Drive, Farmington Hills, MI 48331-3411. Two useful publications are the ASCC Safety Manual, an extensive safety guide for concrete contractors, and the ASCC Employee Safety Handbook. For more information on 水泥, consult the manufacturer's material safety data sheet.