Polymer materials are limited in their heat tolerance, so skimmers equipped with these media may have only tray heaters. Skimmers with steel media can apply heat to both the tray and the medium, which improves performance in severe winter climates. To resist corrosion, a stainless steel housing also may be needed. Aboveground enclosures and underground manway mounting kits provide additional protection from the elements. Nitrile is suitable for use as high as 176 F in neutral pH liquids.
Ceramics are resistant to more chemicals, but are prone to breakage.
For hazardous duty locations with ignitable fumes, explosion-proof motors are mandatory. Special corrosion resistant motor housings may be required for sanitary washdown situations in food plants. Different voltages and power frequencies are needed for some plants. In many applications, skimmers can run unattended for days or weeks. This is typical for groundwater remediation applications at remote well sites.