ASTM F1930

Standard Test Method for Evaluation of Flame-Resistant Clothing
for Protection Against Fire Simulations Using an Instrumented Manikin

Test method used to measure flame resistance of a material, garment or clothing ensemble/systems when exposed to a specified fire. This test method is commonly referred to as the 'manikin test'.
It is important to note that the ASTM F1930 standard outlines a test method and does not include benchmarks or performance requirements. These can be found within other standards. Instead, the aim is to ensure results from different testing laboratories are comparable.

The ASTM F1930 test method predicts the potential human skin burn injury possible for a single-layered garment or clothing ensemble. The test is conducted under laboratory conditions, with a manikin wearing the garment or clothing ensemble. Layered shirt combinations could also be tested using this method.
The measurements gathered using the ASTM F1930 test method can only apply to the specific sample tested for the heat flux, flame distribution and duration specifications set during the test. Standards that refer to and use this test method stipulate these specifications and benchmark results. Standards to refer to and incorporate the ASTM F1930 include NFPA 2733 Standard Specifications for Flame-Resistant Rainwear for Protection Against Flame Hazards and NFPA 2112:2018 Standard on Flame-Resistant Clothing for Protection of Industrial Personnel Against Short Duration Thermal Exposures for Fire. Therefore, when the ASTM F1930:2018 test is conducted, it is done using the specifications outlined within the above standards.
To perform the ASTM F1930 test method, a manikin, propane burners and a coverall constructed out of the test fabric is required. To simulate a flash fire eight propane burners surround the manikin at approximately equal distances. The test manikin is installed with over 100 thermocouples or heat sensors distributed uniformly around its surface. During the simulation flash fire exposure, these thermocouples will measure the depth or intensity of the heat that travels through the fabric.
The manikin is wearing a coverall constructed out of the test fabric. The testing fabric is to be sewn using the coverall pattern dictated by the ASTM F1930 standard. Some standards like NFPA 2112:2018 stipulate this is to be a pattern for a size 42 regular. Underneath the coverall is a 100% cotton T-shirt and briefs. Char marks on these inner garments will be examined and noted to assist in evaluating the body burn average.
During a flash fire simulation, eight propane burners expose the manikin to flames of 84 kW/m2 (2 cal/s cm2) with a typical duration of 3 seconds but can also reach 20 seconds, dependent on the benchmarks from other standards, like those mentioned above.
Upon completing a simulation, the data from the thermocouples and physical assessment from the flash fire simulation are analysed alongside the theoretical skin burn model. This model is derived from predictions made using data from experiments in which human test subjects were exposed to elevated levels of thermal conditions on their forearms. The rate of forearm burning was then applied to the entire body (except the hands and feet) to predict the likelihood of burns.

A calculation is made to predict the extent, severity and location of second and third-degree body burns; the result a percentage. This percentage represents the area of the body that would burn if an arc flash event of such conditions occurred. It is commonly referred to as the 'body burn percentage' and is visualised as a body burn silhouette, seen below. A body burn percentage of 50% or less is required for compliance to NFPA 2112:2016.
ASTM F1930 test reports may also include a record of optical and physical changes to the test samples. This information aids in the overall understanding of the garment's performance in protecting the human skin from burn injuries. These observations indicate the properties of the garment. For example, the absence of char from the inner garments may indicate the test garments ability to provide insulation from the flash fire hazard. This example would otherwise be evident in a low body burn percentage, where other observations may not.

Other observations include:

  • Afterflame: the garment supports combustion with the presence of flames after the flash fire blast
  • Garment degradation: broken or busted seams
  • Carbonization: occurs when the garment is orange peeled, sometimes, the garment also gets darker
  • Shrinkage: Some garments may acquire vertical and/or radial shrinkage
  • Dye sublimation: where the garment has changed colour from blue dyes to pink