A method for environmentally protecting a terminal block includes providing a sealing device including: a base substrate having an anchoring surface; and a gel sealant body having an engagement surface. The gel sealant body is secured to the anchoring surface and extends forwardly from the anchoring surface to the engagement surface. The method further includes: applying the sealing device to the terminal block such that the gel sealant body is interposed between the terminal block and the base substrate and the engagement surface engages the terminal block; and wrapping a retainer member around the terminal block and securing the sealing device to the terminal block using the retainer member.