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Construction is unique. Unlike other sectors, construction workplaces regularly involve multiple employers with a mix of trades that changes over the life of a project. Construction firms are predominantly small with the overwhelming number having less than 20 employees. Smaller contractors incur a disproportionate percentage of injuries and fatalities, which has led to construction consistently having the highest number of deaths of any sector. Most fatal construction injuries are caused by falls to a lower level, being struck by an object or a vehicle, contact with electric current, or being caught‐in or between objects or equipment. Health hazards are not given the prominence of safety hazards in construction because their effects may not be felt for decades and their causes may be unclear. Safety hazards are easier to identify. Seven percent of all OSHA construction inspections are for health hazards. Industrial hygienists should focus on task‐based personal monitoring, rather than time‐weighted averages, to better protect construction workers. Episodic exposures are more common in construction and can be quite elevated. Bystander exposures from nearby trades must also be considered as part of any hazard assessment. Dermal exposures are significant in construction because of the widespread use of cement, adhesive, solvents, abrasive cleaners, spray insulation, and paints. Engineering controls like local exhaust ventilation and wet methods can clearly reduce exposures to construction workers, if made available and maintained. New technological advances, like drones and nanomaterials, are appearing in construction. Industrial hygienists will be instrumental in navigating the benefits and risks of these technologies.

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While the critical task of evaluating the hazards of nanomaterials continues, exposure assessments can provide additional information to safeguard workers. The frequent exposure of construction workers to inhalation hazards underscores a pressing need to characterize and quantify nanomaterials in aerosols generated during construction activities. Research was conducted in partnership with affected building trades unions and in collaboration with NIOSH toxicologists to obtain occupationally relevant exposure data. Initial studies took place in a test chamber, in which a skilled tradesperson sprayed or sanded paints and coatings containing ZnO, TiO2, or Ag nanoparticles. The current study, conducted outdoors, investigated exposure to graphene nanoplatelets during cutting, grinding, and tuckpointing of cementitious composites. Personal breathing zone samples were analyzed for elemental carbon (EC) respirable mass concentration and by transmission electron microscopy (TEM) with energy-dispersive x-ray spectroscopy. Wet methods and local exhaust ventilation effectively reduced exposure to graphene; respirable EC was non-detectable when using exposure controls versus up to 3 mg m-3 without. A high proportion of graphene particles observed by TEM were free and not bound to the cement matrix. Compared to the unincorporated graphene, the dimensions of graphene particles observed in air samples were smaller, suggesting a potential physical transformation prior to release from the matrix. Given the dustiness of construction environments, analysis of filter loading prior to collection of TEM samples proved methodologically valuable. These results provide actionable information about exposure risks and controls and support further investigation of the extent to which graphene may alter the toxicity of cement dust.