The following PDF is the NFPA Code for the above ground storage tank (AST) installation.
On page 4, Section 188.8.131.52.3, letter C the code states the following:
Means shall be provided to prevent overfilling by sounding an alarm when the liquid level in the tank reaches 90 percent of capacity and by automatically stopping the delivery of liquid to the tank when the liquid level in the tank reaches 95 percent of capacity. In no case shall these provisions restrict or interfere with the proper functioning of the normal vent or the emergency vent
Our Overfill alarms, when mounted to our standard liquid level gauge (Therma Gauge), provide a 110 DB alarm to warn that the tank is reaching capacity. The following documents provide testing results and ordering info:
- 90% Overfill Gauge Ordering
- Intrinsically Safe Documentation on the gauge alarm
- Recommended Maintenance and Installation Procedure on liquid level tank gauges
In cases where liquids are flammable and fire protection is paramount, adding the Glass Calibration and the Aluminum Lock Nut to the gauge should eliminate the plastic from the gauge and provide a glass and metal barrier between the inside of the tank and the outside. For additional protection, upgrade the Aluminum Nut to the Gauge Guard.
Already have a Krueger Gauge and want to get it up to code. If the gauge is fully functional, just order our upgraded Fire Protection Gauge Repair Kit and an overfill alarm. In the case of the kit, we will need to know what gauge type you have. Example part number is (-”gauge type”-Kit-GLC-ALN). Both the kit and the alarm are easily retrofitted to existing Krueger Tank Gauges.