Metal halide bulbs will run at temperatures in excess of 600 degrees F. At these high temperatures any spec of water or even a cold draft from an AC vent can cause them to break. It is important that you place the metal halide lamps high enough off the water to prevent water splashes from hitting them or run them in a pendant housing with a tempered UV shielded glass cover.
We do not warranty any lamps that have any sign of water stains on the glass. Saltwater scars the lamp glass when it is hit while burning making it easily detectable to us for this neglect. Running a SE mogul base lamp without a glass shield is OK to do but you take the risk of damaging the lamp from water splashing it by doing this. Cool water hitting a hot lamp damages the inner arc tube and will shorten the lifespan of the bulb and alter the color temperature of the lamp.