Salt Fog Chambers are a critical testing device for monitoring the effects of humidity, moisture and salt on metals. Fluoramics has constructed several inexpensive chambers and taken them to trade shows where they have been well received.

The chambers allow for quick on-site testing. They are scalable, flexible and they parallel the ASTM B117 testing standards.

Background

The basic elements for meeting the ASTM B117 standards are: 1) a controlled temperature of 100 degree F; 2) a 5% salt solution; and 3) a condensing fog environment.

Bill of Materials

• A lidded, semi-sealable or sealable plastic container.

• Any high-quality, lidded container from a local hardware
supply or a food-grade serving container.

• An internal mounting frame to hold the test pieces.

• Customize the frames for your test samples.

• Stainless steel, pvc tubing, polycarbonate sheet stock all work.

• A programmable temperature controller with thermocouple feed-back to control water temperature.

• A silicone heating pad.

• A low-cost ultrasonic fogger.

• Oil absorbing fiber pad(s).

• Fiberglass insulating pads.

Chamber Setup

1. Assemble the chamber and fill it with a 5% saline solution.

2. Turn on the heater programed to 100 degrees F,  and turn on fogger.

3. Let stabilize at temperature and verify/observe fogging.

4. Qualify the chamber with your Engineering Department.

5. Start running samples with time evaluations.

Notes and Observations

1. To minimize solution contamination, place oil absorbing pads under the test pieces inside the tank to capture drippings.

2. Life cycle of the ultrasonic foggers is estimated to be 500 to 1000 hours in this environment. Cost of the foggers is minimal and should be accepted as a “use and throw away” item.

Questions

• Contact Fluoramics, Inc. via email at “ask an engineer” on our website (https://www.fluoramics.com/ask/), or

• Call (507) 205-9216