Wetting agents such as UltraWet® or low-dosed foam concentrates like STHAMEX®-Performance reduce the surface tension of water. This allows the water to adhere better to solid surfaces and penetrate more deeply into porous or hydrophobic (water-repellent) materials. This phenomenon is known as the wetting effect.

In firefighting, the wetting effect means that water – when combined with a wetting agent – no longer beads up but instead spreads evenly across burning materials or materials threatened by fire whilst penetrating them. As a result, the water can cool burning solids more quickly and effectively and reach deep-seated embers that would be difficult to access with plain water.

Wetting agents are therefore used particularly in vegetation or wildland fires to improve penetration into dry, water-repellent substrates such as needles, leaves, or peat, and to increase extinguishing efficiency. Water consumption is significantly reduced, which shortens operation times and simplifies logistics.

In municipal firefighting, wetting agents are also used to minimize water damage during fire suppression efforts.