Excerpted from the 2001 NIJ Report "The Selection and Application of Body Armor"
Note: Body Armor should be cared for and handled as specified by the documentation you received from the manufacturer when you purchased your body armor. The below information should be used as a guide, but not as a replacement for that information.
The proper care of today's modern body armor requires taking precautions when cleaning the garment. Every model of armor that complies with NIJ standards has an instruction label indicating how to clean the components. Individuals should follow these instructions, making certain that anyone else who cares for the garment is also aware of the correct cleaning procedures.
The protective panels, or inserts, of body armor should be washed by hand with cold water, using a sponge or soft cloth and mild home laundry detergent. Most manufacturers strongly recommend that the protective panel never be submerged in water. Bleach (including non-chlorine or peroxide-based bleach) or starch, even when highly diluted, should not be used as these may reduce the garment's level of protection. If a model of armor has a removable carrier, it is possible that the carrier may be machine washable. However, it is imperative to follow the manufacturer's care instructions found on the protective panel and carrier labels.
Body armor panels or inserts are not to be machine washed or dried, either in the home or commercially. The fabric can be damaged by laundry equipment, ultimately affecting its performance. Commercial laundries also use commercial detergents, which are much harsher than home detergents, and pose another threat to maintaining the ballistic- or stab-resistant properties of the fabric. According to DuPont, perchlorethylene is the only dry cleaning solvent found so far that does not significantly degrade the ballistic protection provided by current body armor. However, to eliminate the possibility of an accident and avoid the variety of dry cleaning solvents in use, dry cleaning armor is not recommended.
Most modern body armor contains water-repellant treated or inherently water-repellant fabrics, making hand washing possible by preventing the water used to wash the vest from degrading the ballistic capabilities of the vest. However, rinsing thoroughly is still important to remove all traces of soap. Rinsing properly prohibits the accumulation of residual soap film, which can absorb water and reduce the protective properties of certain types of ballistic- or stab-resistant fabric.
Body armor fabric should never be dried outdoors, even in the shade, as ultraviolet light is known to cause degradation of certain types of ballistic fabric. Tests have demonstrated that ballistic efficiency is significantly and adversely affected by exposure to sunlight for extended periods of time.
Each time body armor is washed, it should be inspected for any signs of wear. If the protective materials are not covered with a permanent cover (which is highly uncommon for a typical modern vest), and it appears that the thread used to sew layers together is wearing badly or that the fabric is unraveling, the vest should be returned to the manufacturer for replacement. Officers should never attempt to repair armor themselves under any circumstances.
Today, most manufacturers market concealable body armor with the protective panel sealed within a moisture barrier, such as thin rip-stop nylon or coated cloth, instead of chemically waterproofing the fabric. The owner of such armor must routinely inspect it to be sure that the cover of the protective inserts has not been cut or damaged, which would allow moisture to penetrate the protective panel. Even if the outer covers have not been cut or otherwise damaged, the moisture barrier can still be damaged. When the protective material or the outer shell carrier rubs over the protective panel cover as a result of the normal flexing that occurs when body armor is in use, it can wear through the cover and expose the armor to moisture penetration. It should also be noted that certain types of covering materials tend to make the armor much warmer to wear, because it significantly reduces the rate at which perspiration can evaporate or be absorbed.
The exceptional ballistic- and stab-resistant efficiency of materials used to construct body armor compensates for any of these limitations associated with maintenance and care. The user can easily care for and properly maintain body armor and ensure that it provides its rated protection throughout its service life.
When caring for hard armor, it is important to remember that hard body armor, particularly ceramic material, must be handled carefully because it is fragile. Ceramic materials--such as boron carbide, aluminum oxide, or silicon carbide--are extremely brittle. Such armor should not be dropped on hard surfaces and when used, the ceramic must serve as the striking (exterior) surface. It should also be inspected before each use to ensure that no surface cracks are present that would degrade ballistic performance.