CMAXX Inline Deflagration Arrester: Explained and Compared

May 9, 2022

The CMAXX Inline Deflagration Arrester (IDA) is a proprietary filter design of Imperial Systems. Each collector with IDA filter technology displays a special IDA seal affirming the unit is a certified IDA collector. This certification is in effect as long as replacement collector filters are always Imperial Systems IDA filter elements. Let’s explore the details of our IDA filter technology and its advantages over what other dust collector suppliers offer.

CMAXX as an Inline Deflagration Arrester 

It’s important to understand that IDA certification is for CMAXX as a whole system with specific features and configuration. It’s been third-party tested to withstand an explosion of 185 Kst. If a deflagration occurs in the collector, it will completely stop a flame from passing beyond the filter section.

Four still frames from video of deflagration test of CMAXX Inline Deflagration Arrester

IDA FiltersDeltaMAXX IDA (Inline Deflagration Arrestor) filter is specially designed to withstand an explosion

 To begin with, these are not ordinary cartridge filters. We use a proprietary IDA version of our DeltaMAXX Prime filter. It has a second layer of reinforcement that makes it stronger to withstand high Kst explosions. With IDA DeltaMAXX filters in CMAXX, the explosion force will pass through, but the fireball won’t.

The filters will burn eventually if there’s a fire in the dust collector. The filter media itself is flame resistant and with the initial explosion they won’t burn up. If there’s a flame that continues to burn in the collector after the explosion, the filter media may eventually burn away. A standard filter with standard cellulose media would burn up and a fireball would go right through it.

Electric Eye

The IDA package includes a photoelectric sensor. The system installer will put this into the ductwork downstream of the collector. This sensor acts as a broken bag detector to monitor for any compromised IDA filters in normal operation. The sensor will send a signal to a warning device. It may otherwise shut the system down if it detects particulate bypassing the filter section. This is an important feature of the IDA system. That’s because a damaged filter will allow the flame to get through in a deflagration event. If the sensor detects something passing through, the indication is that there’s a problem with a filter. Maintenance personnel will need to replace it. 

What Competitors Do

Other manufacturers will offer a second bank of filters. This is to perform the same function as Imperial Systems’ tested and proven IDA filters. There are ramifications of this to consider.

First of all, enlarged collector housings accommodating two sets of filters take up more space. Some companies build another complete filter section on top of their collector to retain the footprint. But this results in a tall collector that decreases headroom for indoor installations. This increased filter housing will also add a considerable amount of extra cost to the collector. However, CMAXX IDA technology does not require this.

Furthermore, secondary filters can prematurely blind since they’re not self-cleaning. This can result in high pressure drop. Plus, there’s an initial extra cost of the larger housing with a second filter set. Further, its replacement costs are more frequent than the primary filters.

No Diverter Valve or Abort Gate Needed

The National Fire Protection Association (NFPA) says that you have to block off all your egress from your collector. So, the ductwork coming into the collector has to have an explosion isolation valve/damper in the ductwork. If the outlet’s clean air is going back into the plant, it must have a diverter valve. 

Our CMAXX Inline Deflagration Arrester actually negates the need for that diverter valve or abort gate on the collector’s outlet. That’s because our filters will stop that flame from passing through the filter section.

No Secondary Filter Bank Needed

Our IDA DeltaMAXX filters alone do what competitors do with two sets of filters to stop a flame front. Changes of one set of our primary filters are easy and safe with the patented lift rails in the CMAXX. The safety pentagon built into each CMAXX collector prevents the doors from closing if rails are not locked in the proper upright position, ensuring filter sealing. No secondary filter bank means no added risk of filter bypass allowing a flame to travel through.

Dust and Fume Applications

When can you use, or not use, the CMAXX IDA technology? As we learned earlier, it’s been tested and certified to withstand dust explosions at 185 Kst. So, we need to know or determine what that rating is for your dust and/or fume application. 

This infographic identifies Kst values for several dust types. Sugar and cornstarch are highly explosive, yet the CMAXX IDA will stop a flame front from their ignition. Cornstarch was actually used in the deflagration test. Most metals have Kst values much higher than 185, so they’re not good candidates. Just about any dust that’s 185 Kst or below would be an excellent choice.

Installation Location Flexibility

We have customers who have no other option than to locate their dust collectors inside of their plants. With explosive dust, they can place the collectors next to an outside wall so the explosion can vent outside. 

Alternatively, they can equip a flameless vent explosion suppressor onto the collector’s explosion vent. Normally, the exhausted air would also need to vent outside. Alternatively, you can equip the collector with a costly chemically suppression system and high-speed isolation gates. But with our IDA, they can keep the collector inside and not worry about venting the air outside. It can discharge right into the plant because there’s no flame that’s going to come by. This opens up many options for CMAXX IDA installation locations.


Summing Up the CMAXX Inline Deflagration Arrester for Fire or Explosion

Official logo certifying that CMAXX Dust Collector is an IDA (Inline Deflagration Arrester)

  • The CMAXX Inline Deflagration Arrester has been independently tested and proven to meet NFPA standards for stopping a flame front from fire or explosion. 
  • It eliminates the requirement for a diverter valve or abort gate at a collector’s discharge. 
  • It eliminates the need for a secondary bank of filters designed to stop a flame front. 
  • Unlike secondary filters used by others, CMAXX consistently cleans the IDA DeltaMAXX primary filters during operation. 
  • The CMAXX IDA is the best choice for explosive dust with a rating of 185 Kst or lower.

Learn more about the CMAXX Inline Deflagration Arrestor.