MIL MIL-PRF-39003N covers the general requirements for established reliability, insulated tantalum, electrolytic (solid electrolyte), fixed capacitors, hermetically sealed 1/ in metal cases (see 6.1). Rated voltages range from 6 to 100 volts dc with surge voltages of 8 to 130 volts dc, respectively (see 4.7.19). These capacitors are designed for full rated voltage operation between -55° and +85°C, derated linearly between +85°C and +125°C to the value shown in table I. A part per million (PPM) quality system is used for documenting and reporting the average outgoing quality of capacitors supplied to this specification. Statistical Process Control (SPC) techniques are required in the manufacturing process to minimize variation in production of capacitors supplied to the requirements of this specification. These capacitors have reliability ratings established on the basis of life tests performed at specified voltage at +85°C for Failure Rate Levels (FRL's) ranging from:

• 1.0 percent per 1,000 hours to 0.001 percent per 1,000 hours in accordance with MIL-STD-690. These FR levels are established at a 60-percent confidence level and are maintained at a 10-percent producer's risk (Exponential distribution).
• 0.1 percent per 1,000 hours to 0.001 percent per 1,000 hours at a 90-percent confidence level (Weibull distribution).