Studies have shown that porous ballistic panels and blocks break down much faster. Porous surfaces will sponge in water that will, over time, cause breakdown and flaking. In freezing environments, the water will seep into the blocks or panels and freeze, causing more damage when rounds hit frozen blocks.
However, another issue arises in range safety regarding porous surfaces. The sponging ability of porous blocks and panels can also pull in contaminants. Lead dust and gunpowder can get into porous ballistic blocks and panels. Porous blocks and panels are much more challenging to clean.
According to the National Air Filtration Association (NAFA), the most dangerous areas for any shooter or employee at a firing range concentrates in three places: the shooting station, the area 15 feet from the shooting station, and the target area. These are the areas where toxic pollutants exist at the highest levels of concentration.
The inability to clean these areas and surfaces makes the range more dangerous. Contaminants you can’t get out will get into porous surfaces. These contaminants can range from lead to gunpowder. The lead can make the surfaces in the range toxic, and the gun powder can increase the fire hazard factor.
Experts suggest to combat this, make as much of the range as cleanable as possible. When considering ballistic rubber products, it is essential to choose non-porous parts to reduce this risk. You can tell the difference between porous and non-porous by observing the face of the product. Porous products will have chipboard or sponge looking front.