As previously discussed, to reproduce the harsh conditions to which capacitors may be subjected when assembled in an external meter application, the following test conditions have been standardized: a humidity level of 85% rH, 85°C temperature, and 290 VAC for a duration of 1000 hours with a maximum capacitance drift of ±10%. In the diagram shown, the heavy duty demonstrates very stable performance compared to the standard series that after 100 hours started to show excessive degradation.