apparent source. Concentrations of acetic acid and cyclohexane were below the NIOSH RELs of 25 and 1,050 mg/m3, respectively. Formaldehyde concentrations were 0.023, 0.024, and exceeding the NIOSH REL of0.02 mg/m3. The most likely source of the formaldehyde was the CCP records located throughout the center.
Thompson 1996. Thompson [1996] reported measurements of indoor air quality in an unpublished U.S. study of 75 workers who continuously handled CCP in the finance and accounting building of a university. This building had a history of indoor air quality problems and medical complaints from workers dating from 1992. The relative humidity, temperature, and mold and fungus counts were within the American Society of Heating, Refrigerating, and Air-Conditioning (ASHRAE) limits of 40% to 60% relative humidity, 74 to 78 °F temperature, and low indoor spore counts (relative to outside counts for mold and fungus) [ASHRAE 1981]. The carbon dioxide concentration was 1,000 ppm, which exceeded the
ASHRAE standard [ASHRAE 1989]. Corrective actions to the ventilation system included repair of the heating, ventilating, and air-conditioning system, increased outside fresh air supply, earlier air-handling startup times, and increased air circulation (which decreased carbon dioxide concentrations to 400 to 700 ppm).
Area air samples were collected in two locations of the CCP building and compared with an air sample from another building that had 60 occupants, no history of medical complaints, and minimal use of CCP. GC/MS standards were prepared from the CCP forms (all three sheets, top sheets alone, and bottom sheets alone) and a sample of SurSol 290 (a solvent carrier for dyes used in the production of the microcapsules). Table 3-4 lists the con- centrations of chemicals found in these samples. The sample from the comparison building showed concentrations that were about three orders of magnitude less than those found in the CCP building. Of the chemicals for which
| Area air samples | |||||||
|---|---|---|---|---|---|---|---|
| CCP samples | CCP building | ||||||
| Chemical measured | Top sheet | Bottom sheet | Three sheets | SurSol 290 solvent | Sample 1 | Sample 2 | Comparison building |
| Decane | 13.2 | 0.001 | 7.9 | — | 1.0 | 1.1 | 0 |
| Undecane | 0.02 | <0.001 | 12.7 | — | 0.3 | 0.3 | 0.004 |
| Dodecane | 2.6 | <0.001 | 4.8 | 0.027 | 0.6 | 0.6 | 0.006 |
| meta-, para- Xylene | 0.1 | 0 | 0 | 6.2 | 1.2 | 0.6 | 0 |
| ortho-Xylene | 0.0 | 0 | 0 | — | 0.4 | 0.2 | 0 |
| Toluene | 2.9 | 0.3 | 0.1 | — | 1.3 | 0.5 | <0.001 |
| Ethyl benzene | 0.4 | 0 | 0 | 8.9 | 0.5 | 0.3 | 0 |
Adapted from Thompson [1996].
