into the annular space a second port is also located on the housing and adapted for expelling any fluids whether they be liquids or gases which are present in the annular space prior to the injection of corrosion inhibiting substance the fluids which are present prior to injection often include seawater freshwater air or combinations thereof when the flange is being utilized in the splash zone of a marine environment the ports are preferably capable of being opened or closed by for example a valve the first or second port is also useful for removing for example draining the corrosion inhibiting substance when repair or inspection of the flange is necessary in addition either port or an additional port may be employed to reduce the pressure within the flange protection device in the event of a leak from the flange if leaking from the flange is likely then it may be desirable to include a pressure sensing device within the flange protection device in this manner if a leak does occur the port may be opened to prevent the flange protection device from bursting the first and second port may be located anywhere on the housing so long as the existing fluids in the annular space are ejected upon the introduction of corrosion inhibiting substance generally it is most convenient and practical to orient the two ports such that gravity may be used advantageously for example when the first port is located below the second port then the introduction of corrosion inhibiting substance pushes the existing fluids upward and out of the second port into the.