7 Determination of Potential for Fire Hazard7.1 In addition to visible signs of fire, non-compliant test results for fire shall also include an evaluation for potential flammable concentrations of vapors during testing if there is the potential for combustible vapor concentration based upon the technology and design of the EESS. For detection of potential flammable concentrations that may be emitted during testing, a gas monitor suitable for detecting 25% of the lower flammability limit of the evolved gases being measured. A minimum of two sampling locations where concentrations may occur such as at vent openings or vent ducts shall be used for taking measurements.Exception: As an alternative to using gas detection measurement to determine if there are flammable concentrations, non-compliant tests results for fire may include an evaluation for potential flammable concentrations of vapors with the use of a minimum of two continuous spark sources. The continuous spark sources are to provide at least two sparks per second with sufficient energy to ignite natural gas and are to be located near anticipated sources of vapor such as vent openings or at the vent duct.7.2 Additional precautions shall be taken during tests requiring this analysis due to the potential for flammable gas concentrations that may occur within the test room or chamber.