ASTM 1959
Standard Test Method for Determining the Arc Rating of Materials for Clothing
This is the test method used to calculate quantitative results for fabrics relating to how they perform in an electric arc environment.
5.1 This test method is intended for the determination of the arc rating of a material, or a combination of materials.
5.1.1 Because of the variability of the arc exposure, different heat transmission values may be observed at individual sensors. Evaluate the results of each sensor in accordance with Section 12.
5.2 This test method maintains the specimen in a static, vertical position and does not involve movement except that resulting from the exposure.
5.3 This test method specifies a standard set of exposure conditions. Different exposure conditions may produce different results. In addition to the standard set of exposure conditions, other conditions representative of the expected hazard may be used and shall be documented in the reporting of the testing results.
•The purpose of this test method is to determine how much heat a certain fabric (or system of fabrics) will block from an electric arc before the onset of second degree burns for the wearer.
•The amount of energy blocked by the fabric is reported as Arc Thermal Performance Value (commonly abbreviated as ATPV). The value is reported as Breakopen Threshold Energy (Ebt) if the fabric breaks open before the onset of second degree burns is reached.
•Heat Attenuation Factor (the percentage of total heat blocked by the fabric from reaching the sensor) is also determined.
•Test results from ASTM F1959 must be reported for all garments that meet ASTM F1506.
| Risk Category | Clothing Description | Required ATPV of the Garment System (cal/cm2) |
| 0 | Non-melting, flammable materials (i.e. untreated cotton, wool, rayon or silk, or blends of these materials). | N/A |
| 1 | • Arc rated FR shirt + FR trousers or arc rated FR coverall | 4 |
| 2 | • Non FR undergarment • Arc rated FR shirt + FR trousers or arc rated FR coverall.8 | 8 |
| 3 | • Non FR undergarment • Arc rated FR shirt + FR trousers or arc rated FR coverall • Arc flash coverall selected so that the system garment arc rating meets the required minimum. | 25 |
| 4 | • Non FR undergarment • Arc rated FR shirt + FR trousers or arc rated FR coverall • Arc flash coverall selected so that the system garment arc rating meets the required minimum. | 40 |