In addition to protection from exposure to hazardous agents in the environment, a completely effective protective garment must also minimize physiological burden and prevent the risk of heat stress. The garment should allow facile perspiration and efficient heat loss from the body by evaporative cooling. Unfortunately, the techniques for protection and breathability (i.e., rapid water vapor transport) often work at cross purposes in a single material. Current protective materials sacrifice breathability in order to prevent exposure to harmful agents. They are typically either impermeable barriers that entirely block penetration of chemical and biological hazards (but also of water vapor), or heavy-weight laminates containing adsorbents for harmful agents.

Macroporous membranes with high permeability to moisture vapor and air offer poor protection from hazardous materials. Because the ability of these materials to protect typically relies on hydrophobicity/oleophobicity, low-tension liquids can penetrate their porous network structure and potentially shuttle in other hazardous components. Furthermore, these macroporous materials are ineffective against vapor phase threats.

Recent approaches to achieve adequate breathability in protective materials typically encompass selective monolithic membranes made of novel hydrophilic polymers, or multifunctional materials containing chemical groups/oxide nanoparticles with antibacterial or self-decontamination ability.