The "Sink Effect" in Public Spaces
- Sher
- 2 days ago
- 3 min read
The “sink effect” identified in research commissioned by the U.S. Access Board. Fragrance chemicals are documented to “adsorb to virtually all indoor surfaces,” where they are retained and re-emitted for months after a fragrance-emitting device is removed (NIBS, 2006).
Key Mechanisms of the Sink Effect
Adsorption: Volatile Organic Compounds (VOCs) and chemical vapors "stick" or adsorb to indoor surfaces.
Surface Roughness: Chemicals bond much more strongly to rough surfaces (like carpets, fabrics, and unfinished wood) than to smooth surfaces.
Desorption: The surfaces later re-emit these trapped chemical pollutants back into the indoor air.
Longevity: This cycle of trapping and re-releasing pollutants can persist for years, sometimes spanning the entire service life of a building.
The U.S. Access Board commissioned this research because the "sink effect" can trap elevated concentrations of airborne chemicals. This severely impacts people with chronic respiratory diseases, fragrance sensitivities, migraines, auto-immune diseases, Multiple Chemical Sensitivities (MCS), and many more, making indoor spaces inaccessible or hazardous for them.
US Access Board, Architectural Design Standards for buildings normally require high-quality non-porous materials like Stainless Steel, Quartz, and Ceramic Tile to ensure hygiene and help alleviate the sink affect for sensitive populations.
The standard is found in the "Building Products & Materials" section of the U.S. Access Board's Indoor Environmental Quality (IEQ) report.
The intentional aerosolization of fragrance compounds forces surfaces to function as chemical reservoirs. Remediation of these spaces after deployment requires active, costly efforts beyond simply discontinuing use, as the building materials themselves will continue to emit air pollution that renders the environment still inaccessible to sensitive populations.
You cannot remediate this harm simply by halting use; active intervention will be required, at additional cost, to restore accessibility.
The U.S. Access Board's IEQ report specifies that contaminated areas should be managed through continuous isolation, targeted exhaust, and specific ventilation protocols. Key recommendations include sealing return air openings in contaminated zones, exhausting air directly outdoors, and performing daily pre-occupancy air exchanges.
The ventilation, material selection, and air-quality protocols outlined by the U.S. Access Board benefit a wide range of individuals.
Vulnerable and Chronically Ill Populations
Asthma and Allergy Sufferers: Eliminating porous surfaces reduces dust mites, mold spores, pollen accumulation, and VOC absorption, while advanced ventilation removes acute respiratory triggers.
Immune-Compromised Individuals: Non-porous, easily sanitized materials prevent the harbor and growth of bacterial and fungal pathogens, protecting chemotherapy patients or transplant recipients.
People with COPD and Emphysema: High-efficiency air filtration and low-no-VOC environments reduce respiratory stress and lower the frequency of severe breathing flare-ups.
Individuals with Cardiovascular Disease: Studies show that cleaner indoor air with lower particulate matter (PM2.5) reduces systemic inflammation and minimizes the risk of acute cardiac events.
Pregnant Women and Developing Fetuses: Minimizing early exposure to developmental toxins and endocrine-disrupting chemicals found in standard building VOCs protects fetal health.
General Commercial Building Occupants
Office and Office Workers: Mitigating the "sink effect" eliminates Sick Building Syndrome (SBS), which causes general headaches, fatigue, and eye irritation among standard office staff.
Children and Students: Children breathe more air relative to their body weight than adults; cleaner indoor air improves concentration, test scores, and reduces school absenteeism.
Elderly Residents: Older adults spend significant time indoors and have naturally declining respiratory reserves, making them highly sensitive to subtle air pollution.
Maintenance and Janitorial Staff: Using non-porous materials that do not require harsh chemical finishes protects cleaning crews from chronic occupational chemical exposure.
Comments