Note: For information on AZ’s measurement services for reflectance, emittance and SRI toward LEED certification, see Optical Measurement Services.
AZ Technology’s newly released SRI 1000 Portable Emissometer/Reflectometer and Solar Reflectometer, is compact,
lightweight, rugged, and ergonomically engineered for ease of use in the field, the laboratory, or on the manufacturing line, to determine ambient temperature total thermal emittance and solar absorptance (at air mass 1.5) of test surfaces for terrestrial applications. These two measurements allow the calculation of the Solar Reflectance Index (SRI) as defined for environmental certifications such as Cool Roofs and LEED.
The SRI 1000 can be conveniently used in a laboratory or manufacturing
setting (top right image) where samples can be sat atop the instrument and right while repeated measurements are being taken.
The SRI 1000 provides in a single unit:
1) A portable emissometer/reflectometer that performs optically integrated total hemispherical reflectance measurements from approximately 3 to 35 micrometers wavelength, yielding total hemispherical thermal emittance measurements.
2) A portable solar reflectometer that performs optically integrated total hemispherical reflectance measurements at air mass 1.5.
These two measurements can be used as per ASTM E1980 to calculate the Solar Reflectance Index (SRI).
The instrument includes a rolling carrying case, 2 rechargeable batteries, battery charger, instrument inspection head, display unit, and an operator satchel for portable use.
The table below lists specifications for the SRI 1000.
| Emittance wavelength range | 3um to 35um |
| Solar reflectance wavelength range | 250 to 2500 nm |
| Measurement accuracy | Within 1 to 3 percent of full scale depending upon the material.* |
| Repeatability | ± 1% of full scale or better |
| Material type | Virtually any opaque material** |
| Sample size and geometry | -Greater than 0.5 inches (1.25 cm) diameter -Flat or a moderate amount of curvature |
| Sample temperature | Room Temperature, Ambient |
| Readouts | -Digital LCD display -Internal data storage, downloadable as .csv file. |
| Dimensions | -Optical Head: 5″ diameter x 8″ long -Control and Display Unit: 7.5 x 5.5 x 3 inches -Battery Box:6 x 3 0.75 inches |
| Warranty | 1 year parts and labor |
*Most natural and common materials are measured within ±2 percent.
**Materials that transmit light in the wavelengths of interest can be handled in some cases (instructions provided).