Concrete Safety: Hazard Recognition and PPE for Flatwork

Why Concrete Safety Matters

Concrete flatwork looks straightforward — mix, pour, screed, finish. But the jobsite risks are real and can cause permanent injury or death. Wet concrete contains portland cement, a caustic material with a pH between 12 and 13. Cutting or grinding hardened concrete releases respirable crystalline silica. Ready-mix trucks weigh tens of thousands of pounds. Cold or hot weather changes how concrete behaves and how your body responds. Knowing each hazard and the right control before work begins is your first line of defense.

Chemical Burns: Skin and Eye Hazards

Wet concrete is highly alkaline. Prolonged skin contact causes chemical burns that may not appear for hours — by the time you feel pain, damage is already done. "Cement burns" can be severe enough to require skin grafts. Eyes are even more vulnerable; a splash of concrete slurry or mixing water can cause permanent damage.

Controls:

• Wear waterproof, alkali-resistant rubber or nitrile gloves. Note that standard nitrile gloves slow penetration but thick rubber gloves give the best protection for extended contact.
• Wear rubber boots that extend above the ankle — never low-top sneakers on a pour.
• Wear safety glasses at minimum; a face shield is required when mixing, pouring from a truck chute, or using a pump hose.
• Change out of concrete-saturated clothing immediately.
• If concrete contacts skin, flush thoroughly with clean water. If it contacts eyes, irrigate with clean water for at least 15 minutes and seek medical attention.
• Wear knee pads with a waterproof outer shell when kneeling on fresh concrete during finishing.

Respirable Crystalline Silica

Silica is a mineral found in sand and stone — and therefore in concrete. When concrete is cut, cored, ground, or jackhammered, it generates dust particles small enough to reach deep lung tissue. Long-term exposure causes silicosis, an incurable and potentially fatal lung disease. It also increases the risk of lung cancer and kidney disease.

OSHA's Respirable Crystalline Silica standard for construction (29 CFR 1926.1153) requires employers to limit worker exposure. For most common concrete tasks, Table 1 of that standard lists specific engineering and work-practice controls that, when followed correctly, satisfy the exposure limit without individual air monitoring.

Key controls for flatwork tasks:

• Wet cutting with a handheld angle grinder or walk-behind saw: use a continuous-flow water delivery system to suppress dust at the blade. A half-face respirator with appropriate filters is also required when wet methods alone may not provide adequate control, depending on the specific tool and Table 1 entry.
• Vacuum-equipped grinders and sanders: use a tool-mounted shroud connected to an industrial vacuum with a HEPA filter.
• Jackhammering or chipping: wet methods or vacuums plus a half-face respirator rated at APF 10 (an N95 or P100 half-face piece respirator).
• An N95 respirator is the minimum respirator used for silica tasks where Table 1 requires one; a half-face elastomeric respirator with P100 cartridges provides higher protection.
• Never use compressed air to blow dust off surfaces or clothing.
• Restrict access to dusty areas; rotate workers to reduce exposure time when engineering controls alone are insufficient.

Struck-By and Caught-Under Hazards During Concrete Delivery

Ready-mix trucks and concrete pump trucks are large vehicles operating in tight spaces. Struck-by incidents occur when workers stand in the swing path of a truck chute or near reversing vehicles. Caught-under incidents can occur if a concrete form or shoring system collapses while workers are near it.

Controls:

• Designate a spotter when any vehicle reverses on the site.
• Establish and enforce exclusion zones around the truck chute during discharge.
• Never stand under or behind a chute that is being repositioned.
• Inspect formwork and shoring before the pour; verify bracing is adequate for the weight of wet concrete.
• Wear high-visibility vests when working near moving vehicles.
• Hard hats are required on all active construction sites.

Hot and Cold Weather Risks

In hot weather, workers face heat exhaustion and heat stroke. Strenuous finishing work raises core temperature quickly, and concrete work often occurs on reflective, sun-heated surfaces. Drink water regularly — do not wait until you are thirsty. Take rest breaks in shade. Know the signs of heat illness: heavy sweating, weakness, nausea, confusion.

In cold weather, hypothermia risk rises, especially when hands and knees are wet from contact with concrete. Cold also affects how concrete sets — accelerators or heating measures may be used, which can create additional chemical or fire hazards depending on the method. Wear insulating, waterproof layers; keep dry.

Job Hazard Analysis (JHA)

A JHA is a written document that breaks a job into steps, identifies the hazard in each step, and records the control measure. For a flatwork pour, a complete JHA would include at minimum: receiving the ready-mix truck, placing and screeding, power troweling, cutting control joints, finishing and curing, and cleanup. For each step you list who or what could be harmed, and how you will prevent it. A JHA completed before work begins is one of the most effective safety planning tools in construction.