Common use of Relative Humidity Clause in Contracts

Relative Humidity. Relative humidity was measured using an aspirated Climatronics 102425 lithium chloride sensor. The manufacturer-reported accuracy is less than ±3% RH in the range 10-90% RH. A DRI site audit in October 2002 included collocation of a continuously measuring Vaisala HMP35C sensor. Figure 5-1d shows the collocated hourly data. A reduced major axis regression yielded: Audit = (0.98 ± 0.02)× Site + (0.8 ±1.1 %RH ) The regression slope is statistically indistinguishable from unity and the intercept is statistically indistinguishable from zero (95% CL). Collocated precision was 1.1% RH (1.8% relative precision) for the 63 hours of collocated data, meeting the manufacturer-reported accuracy of less than ±3% RH. Wind speed was measured using a Climatronics 102083-G0-H0 (Wind Mark III series) anemometer at 10m. The manufacturer-reported accuracy is ±0.11 m/s or 1.5% with starting threshold less than 0.45 m/s. A DRI site audit in October 2002 included an evaluation of the sensor’s starting threshold using a torque wheel at a torque of 0.3 g/cm. The sensor shaft was turned at five constant speeds (0-1000 RPM) and the site sensor speed was regressed on the torque wheel speed using an ordinary linear least squares regression yielding (R2 = 1.000): Site = (0.99)× Audit + (0.09 mph) An additional check was performed by comparing the hourly-average wind speeds between the Supersite in East St. Louis and an IEPA site in Edwardsville, IL (both measurements at 10m). Data was screened to focus on advective conditions with 1,418 hours at Edwardsville exceeding 4 m/s for the period 5/8/2001-6/30/2002. A reduced major axis regression yielded (R2 = 0.693): WSEdwardsville = (1.00 ± 0.03)×WSSupersite + (0.1± 0.1 m / s) For advective conditions, there is excellent agreement between the 10m wind speeds measured at these two sites separated by ~30 km.

Relative Humidity. Relative humidity was measured using an aspirated Climatronics 102425 lithium chloride sensor. The manufacturer-reported accuracy is less than ±3% RH in the range 10-90% RH. A DRI site audit in October 2002 included collocation of a continuously measuring Vaisala HMP35C sensor. Figure 5-1d shows the collocated hourly data. A reduced major axis regression yielded: Audit = (0.98 ± 0.02)× Site + (0.8 ±1.1 ± 1.1 %RH ) The regression slope is statistically indistinguishable from unity and the intercept is statistically indistinguishable from zero (95% CL). Collocated precision was 1.1% RH (1.8% relative precision) for the 63 hours of collocated data, meeting the manufacturer-reported accuracy of less than ±3% RH. Wind speed was measured using a Climatronics 102083-G0-H0 (Wind Mark III series) anemometer at 10m. The manufacturer-reported accuracy is ±0.11 m/s or 1.5% with starting threshold less than 0.45 m/s. A DRI site audit in October 2002 included an evaluation of the sensor’s starting threshold using a torque wheel at a torque of 0.3 g/cm. The sensor shaft was turned at five constant speeds (0-1000 RPM) and the site sensor speed was regressed on the torque wheel speed using an ordinary linear least squares regression yielding (R2 = 1.000): Site = (0.99)× Audit + (0.09 mph) An additional check was performed by comparing the hourly-average wind speeds between the Supersite in East St. Louis and an IEPA site in Edwardsville, IL (both measurements at 10m). Data was screened to focus on advective conditions with 1,418 hours at Edwardsville exceeding 4 m/s for the period 5/8/2001-6/30/2002. A reduced major axis regression yielded (R2 = 0.693): WSEdwardsville = (1.00 ± 0.03)×WSSupersite + (0.1± 0.1 m / s) For advective conditions, there is excellent agreement between the 10m wind speeds measured at these two sites separated by ~30 km.