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Typical Industries Served

Factory/Plant, Process, Power, Water, Nuclear, Tunnel, Odor Control, Compressor Stations, Mines, Offshore Drilling & Production, Original Equipment Manufacturing


  • Rectangular & Round Dampers
  • Multi Blade & Single Blade Dampers
  • High Temperature Dampers
  • CO2 & Halon Containment Dampers
  • Nuclear Safety Class Dampers
  • Tunnel Dampers
  • Pressure Relief Dampers
  • Power Plant Dampers
  • Heavy Duty Industrial Dampers
  • Wafer Dampers
  • Radial Vane Dampers
  • Backdraft Dampers
  • Zero-Leak Isolation Dampers
  • Blast Protection Dampers for
    • Personnel
    • HVAC
  • Marine Dampers
    • Marine Fire Dampers
    • Air Volume Dampers
    • Balancing Dampers
    • BV, DNV, and Lloyds Certified Dampers
  • Military Dampers


Dampers can be used in any industrial, marine, utility, or power application where the control and/or isolation of air in an HVAC or process system is required.


What are isolation dampers?

There are many types of isolation dampers. The type you use will depend on the type of environment you want to isolate. If you want to contain fire and smoke within an area in order to put the fire out, you’ll need a certified fire isolation damper. In the case where you’d need to isolate an area that could become contaminated with noxious gasses, a zero-leakage man-safe isolation damper is what you’re looking for. This double damper system is set up so that fresh air is forced between two dampers, causing fresh air to leak into both spaces. This allows you to hold the toxic air in its place.

There’s not a one-size-fits-all isolation damper; as a result, it’s important to consult with a company who is familiar with the type of damper application to be certain you’ll get the performance you need.


What kinds of guarantees do your dampers come with?

If you order dampers that work within an Eldridge-designed system, the entire system comes with the Eldridge Guarantee that it will work the way it’s meant to.

Other guarantees will depend on the kind of damper. For example, if the damper is for fire control, it will have been tested by an independent certifying lab and will come with that lab’s certification. If it is custom built to meet a specific performance requirement, then it is guaranteed to meet that performance requirement.

There are few moving parts on a damper, so there’s not a lot that can go wrong with it once it’s been properly designed, engineered, built, and applied. Generally speaking, they can last for about 20 years or longer with minimal maintenance.


Do you supply dampers that can withstand extreme temperatures?

Yes, we have experience in many types of extreme performance dampers, including nuclear dampers and marine fire dampers. These dampers have special components to allow them to withstand extreme highs or lows. For example, high-temperature dampers require exotic metals and exterior insulation. For extreme cold, it can require heat tracing on blade edges and seals. It’s important to discuss temperature needs with your sales engineer.


I need dampers that offer blast protection, but if an accident should occur, how do the dampers get closed?

Don’t worry—you won’t need to manually close your blast-proof damper in an emergency situation!

Typical tornado dampers are held in the open position. They contain an inertial mechanism (usually a spring) that allows the damper to close as the pressure builds up when there is a tornado.

Blast protection dampers can be configured to be normally open or closed. When an open damper is shut in an emergency event, it is to keep an area safely isolated from a blast. In the case where the damper goes from closed to open in the event of a blast, this allows air to move through a system so that ductwork does not explode or implode.

After the event is over, because of their inertial component, the damper blades will go back to their original position. As another option, you can have it set to stay in its emergency position.


I’m not sure what size or kind of damper I need. How can I figure it out?

Often, two dampers can appear the same on the outside, but end up having completely different functions. For example, backdraft dampers and pressure-relief dampers may seem similar, but they offer very different solutions. A backdraft damper opens easily in the direction of airflow with minimal system backpressure. However, a pressure relief damper is designed to stay closed and then open only when the system pressure reaches a specific set point; thus, it imposes a backpressure on the system up to a specified pressure relief point.

It takes years of experience to understand which damper does what. We recommend consulting with a ventilation engineer to determine exactly the right damper for your application. We can supply the most basic rectangular dampers to the most challenging custom-shaped designs. Call us today to speak to a sales engineer or fill out our easy quote form to get more information.