Shower Doors are Not WatertightCorrectly installed shower enclosures are designed to prevent leaks under normal shower conditions. Both excessive water pressure and shower spraying directly at the door can result in leaks, as these situations are not normal to most shower enclosures. As well, cleaning your shower enclosure with the spray nozzle also produces excessive water pressure. If puddles of water collect on the floor outside of the enclosure clean it up as soon as possible or it could damage your flooring.
Note: Shower enclosures are not designed to hold water like a bath tub. Attempting to fill a shower enclosure to the top with water can damage the enclosure.
Towel Bar versus Grab bar Warning
Towel bar and handle bars are not the same as grab bars. Grab bars installed in shower enclosures can aid people with getting in and out of the bath tub or shower. They have been specifically designed to bear a lot of weight. Towel bars and handle bars, on the other hand, do not have the same stability as grab bars and should not be used in the same manner, as they were not designed to support your weight.
Therefore, do not hang from or stand on towel or handle bars. If excessive force is used, these bars could snap off, shattering your shower door.
Please instruct your small children in the proper use of towel and handle bars.
Abrasive Cleanser Warning 
Do not use abrasive or acid-based cleansers on your shower enclosure. These cleansers can scar the metal and/or glass. Although this damage may not occur with a single application, it is always best to use the appropriate cleansers.
Opening and Closing Your Shower Door Warning
Do not use excessive force when opening and closing your shower enclosure. Excessive force could shatter the glass of the enclosure.
Shower Enclosure Structural Warning
Do not hang from or stand on your shower enclosure. It is was not designed to support your weight.
Thunder Warning 
On extremely rare occasions, the sound vibration accompanying a lightning strike can shake glass shower doors to the point that they either shatter by themselves or are shaken into the shower door frame and shatter on impact. For this reason, as a safety precaution, shower doors are manufactured out of tempered glass, which breaks into tiny pieces.
Glass Obscurity Warning
Changing your shower door glass post-installation is an expensive proposition! Therefore, consider all important factors when deciding on obscurity level. If you have a beautiful, private view through the enclosure window, consider having your enclosure made out of clear or Starfire glass. If you prefer privacy, perhaps an obscure pattern is more appropriate. If your shower enclosure is the showpiece of your master bathroom, art glass may be the way to go.