Solvent Adhesive in a Summer School Corridor
An 1,800 sq ft middle-school corridor is being re-floored during summer break with a solvent-based contact adhesive. The corridor has one 36-in. exterior door, two open classroom doors, and no operating HVAC. Outdoor temperature is 90 degrees F; indoor is 88 degrees F and rising. The adhesive pail is marked flammable, flash point 12 degrees C, VOC 250 g/L. Five workers are applying adhesive with 9-in. rollers. A pail is open near the door. Two box fans are set at the exterior door blowing air into the corridor. After 45 minutes, one worker reports dizziness and headache; another says the odor is strong but normal. The GC wants the crew to finish the remaining 600 sq ft before lunch so the school can reopen. No gas monitor is on site. The SDS is in the office trailer.
1. What immediate actions should be taken, and should the remaining 600 sq ft be completed before lunch?
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Stop work and clear the corridor. Move the dizzy worker to fresh air, call for medical evaluation, and do not let them drive. Eliminate ignition sources: no smoking, open flames, switches, or non-explosion-proof equipment. Open the exterior door and use mechanical exhaust, not supply fans, to remove vapors. Notify the GC and school safety officer, read the SDS, and do not re-enter without a calibrated combustible-gas meter and proper PPE. The remaining 600 sq ft is not a reason to continue; dizziness is a symptom of overexposure.
2. Evaluate the ventilation setup. What is wrong with the two box fans, and what controls are needed before work restarts?
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The two box fans are wrong. Blowing into the door pressurizes the corridor and pushes solvent vapor into classrooms and occupied areas; the fans are also not rated explosion-proof. Use explosion-proof exhaust fans at low level near the work area, with make-up air from a clean source, and monitor LEL continuously. Reduce the open pail area and use only the adhesive needed. Evaluate a water-based or low-VOC adhesive approved for the substrate; if solvent adhesive is required, establish a written ventilation plan, rotate crews, and use respiratory protection per the SDS and a hazard assessment. Keep the SDS at the work area.
3. What should be documented and communicated before the school reopens?
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Record the incident, meter readings, ventilation setup, product lot, and corrective actions. Give the owner a re-entry plan with clearance criteria, such as LEL below 10 percent and no odor or irritation, and a schedule for the remaining work. Update the safety plan and toolbox talk. Because the school may reopen, provide the GC with the SDS and notification that solvent adhesive was used.