Louder Intrinsically Safe Alarm

3 years of waiting to finally upgrade the volume on our Instrically Safe products.  The 4 dB volume increase may not sound like much but keep in mind that the dB scale is logarithmic and every 3 dB represents a doubling of volume.  this upgrade applies to the IS-AB alarm box, the IS-T family of tank alarms, and   and the IS-D line of drum alarms.