How does the MRC work?


In the MRC’s open state, moisture and air from the exterior of the vessel pass into the opening, but note how the moisture adheres to the leading edge of the MRC Air-Foil. The moisture travels along the leading edge to the hook, where it collects and drains out of the MRC. Dry air now passes over the hook and into the vessel’s interior.


In the MRC’s closed state, any air or water flow into the vessel interior is stopped by the MRC Air-Foil hook.

For more information on the MRC, click here.

The Coast Guard proves why Zazz beats the competition!

On October 16, 2009, the U.S. Coast Guard released a document titled “Small Fire/Important Lessons", detailing the aftermath of a small engine room fire on board an 83-foot passenger ferry in the Northeast US. The fire was most likely caused by “a leaking pipe fitting attached to the fuel oil filter of the center engine. Fuel sprayed from the rear of the center engine to the port main engine exhaust piping and ignited”.

On board the vessel were “moisture eliminating filters”, which allowed for airflow into the engine room. The filter assemblies were constructed from PVC. The intense heat from the fire caused these PVC components to severely warp and melt.


The incident was investigated by the USCG, who found that the melting of the filter (pictured above) could have potentially caused the assembly to fall on or into the duct before the damper closed. This most likely would have “interfered with the damper operation and possibly have reduced the effectiveness” of the boat’s CO2 extinguishing system.

The USCG investigators went on to note that 46 CFR 116.610 (b) states that “a ventilation duct, and materials incidental to installation must be made of noncombustible material.” 46 CFR 116.610(c) states that “combustibles and other foreign materials are not allowed within ventilation ducts. However metal piping and electrical wiring installed in a metal protective enclosure may be installed within ventilation ducts, provided that the piping or wiring does not interfere with the operation of fire dampers.” The investigators also noted that “consideration needs to be given regarding the materials used should it be subjected to excessive heat carried by high temperature gases".

Zazz Engineering’s MRC vent system is solidly built in the USA from anodized aluminum and stainless steel. A highly versatile solution, the MRC acts as a moisture-rejecting engine room vent, a fire suppressant/containment device, and a weather closure. Our MRC completely complies with the regulations set by the US Coast Guard, unlike the PVC products sold by our competitors!

To read the Coast Guard’s full report on the incident, click here.