Chemicals In Masonry Words: Zach EverettPhotos: Zach EverettMason contractors must deal with chemicals on the job site. One of the main ones comes in the form of dust. Another is acid. From high-rise commercial structures to residential facades, masonry work involves handling raw materials that require careful management, not just for structural integrity, but for the health and safety of every worker on the job site. The primary hazards in our field stem from mixing products, cutting masonry, and masonry-cleaning acids, which have an acid-base reaction. Effectively mitigating these risks is not just a regulatory compliance requirement; it is a professional responsibility to safeguard the long-term well-being of your crew. 1. Handling Dry Masonry Cement Products: The foundation of any masonry project is the mortar. Whether you are using Portland cement, hydrated lime, or pre-blended masonry cements, the dust generated during mixing is a source of respirable crystalline silica. Most of the sand used in mortar is coarse sand, rather than free crystalline silica that can become airborne and respirable. It is always best to do monitoring by an Industrial Hygienist to confirm your workers are under the Permissible Exposure Limit. Crystalline silica is a basic component of soil, sand, granite, and many other minerals. When masonry products are cut, ground, or mixed, this silica can be released into the air as fine dust. Inhaling these tiny particles can lead to silicosis, a progressive, disabling, and potentially fatal lung disease. Best Practices for MixingEstablish a Dedicated Mixing Station: Locate your mixing area downwind from other workers and the main traffic flow of the job site. Use Dust-Suppressing Equipment: Whenever possible, use mixers and/or silos with built-in dust shrouds. PPE Requirements: Again, use an Industrial Hygienist to ensure that you are under the Permissible Exposure Limit. If not, ensure that all workers involved in mixing are fitted for N95 or P100 respirators, receive a medical evaluation for ability to wear a respirator, and receive training on wearing a respirator. You will also need a site-specific safety plan. Housekeeping: Avoid dry sweeping or using compressed air to clean up dust. Use a vacuum equipped with a HEPA filter or wet sweeping methods to keep the site clean without aerosolizing fine particles. 2. Handling Wet Mortar and Cement: While dry mixing presents a respiratory hazard, wet mortar poses a different, more immediate risk: chemical burns. Portland cement and masonry cements are highly alkaline (caustic). When wet cement comes into contact with the skin, it can draw moisture out of the tissue, leading to severe dermatitis, skin sensitization, and, in prolonged contact cases, chemical burns that can require medical intervention. Preventive MeasuresBarrier Protection: Require all employees to wear chemical-resistant gloves. Ensure that pants cover the tops of the boots or that boot covers are used to prevent wet mortar from settling against the skin. Immediate Hygiene: If wet mortar makes contact with skin, wash the area immediately with clean water. Never let wet cement dry on clothing. Training: Ensure your team knows that the 'wet' stage of cement is not 'safe' simply because it isn't airborne. The caustic nature of wet mortar is just as hazardous as the dust is to the lungs. 3. Washing Down Masonry with Acid Products: Cleaning masonry is often the final touch on a project, using masonry-cleaning acids to remove mortar smears and efflorescence. This process introduces corrosive hazards that require strict chemical management. Safety Protocols for Acid WashingDilution Logic: Always add acid to water, never water to acid. Adding water to acid can trigger a rapid heat-producing reaction, causing concentrated acid to splash and potentially injure the user. Ventilation and PPE: Acid vapors can be highly irritating to the eyes and respiratory system. Review the manufacturer’s recommendations for PPE. Ensure the work area is well-ventilated or use an organic vapor respirator if working in confined spaces. Neutralization and Disposal: Have a neutralization agent (such as baking soda or lime) readily available on-site for immediate spill management. A pH measuring kit, available from most swimming pool supply retailers, can be used to check the caustic level of the wash water. Never pour acid wash water into storm drains without neutralization; follow local environmental regulations for proper containment and disposal.Building a Safety CultureSafety in masonry is not just about following rules; it is about culture. And culture is what becomes a normal lifestyle. By creating an environment where workers are trained to recognize the hazards of dry dust, wet alkalinity, and cleaning acids, you protect your most valuable asset: your people. Make safety briefings a standard part of every morning meeting, and ensure that the right PPE is always available, clean, and in good working order. Professional masonry is about building structures that last; protecting the health of the workers who build them is just as vital.About: Safety Library
