Protecting individuals

 

Issues:

NBC respiratory protection

NBC respiratory protection

Whether because of planned, accidental, military, civil, or nuclear conditions, man must sometimes operate in environments filled with particularly aggressive gases. Whatever the reason, his survival depends on specialized equipment that meet precise standards and have the capacity to protect his body and respiratory system. At stake here is what is often referred to as "NBC", meaning "Nuclear, Bacteriological, and Chemical" agent protection.

As filtering agents, activated carbons are an integral part of many such pieces of equipment. Activated carbons are part of gas mask cartridges and are inserted into the ventilation systems of shelters, tanks, plants, or control rooms.

Certain gases are immediately adsorbed by the carbon's microporous structure. Others are neutralized through chemical reaction with the impregnation products borne by activated carbon.

Targeted compounds:

  • VOCs
  • acid gases
  • volatile sulfuric compounds
  • ammonia and derivatives
  • organophosphonates
  • HCN
  • CICN
  • chloropicrine
  • arsine
  • phosphine
  • formalin vapors
  • mercury vapors
  • radioactive iodine compounds

Protecting the people

Protecting the people

Solutions:

Coconut-shell based activated carbons are particularly well suited to civil and military applications because of their very high specific surface area (up to 2,500 m2/g or greater) and their hardness, which facilitates their manipulation and prevents degradation while in use. In this respect, PICA activated carbons offer an exceptional ratio of activity to durability.

  • Civil risks:

Protection of civil and industrial environments is divided into four categories:

type A and AX against organic compounds with high and low points of ebullition,

Type B against acid gases,

type E for volatile sulfuric compounds,

type K against ammonia gases and derivatives.

Tests for the evaluation of carbons are subject to strict standards. The most well-known include standards EN 141 and 143 for Europe, and for the United States "The American standard federal code, part 11: respiratory protection device test for permissivity, sub-part L" and standard NIOSH (National Institute of Safety and Health).

The PICA line of products and services includes numerous activated carbons that meet these standards. But it is not uncommon that PICA specialists are called upon to custom-design activated carbons for specific protection purposes, such as for formol- or mercury vapors.

In any case, granulometries and degrees of activation will be adapted to the constraints presented by the filter manufacturers.

  • Military risks:

Activated carbons used in military operations must function in the most severe conditions of humidity and temperature in order to fully eliminate the most hazardous gases (organophosphates, HCN, CICN, chloropicrine, arsine, phosphine, etc.)

For these applications, PICA has brought together a range of high-performance activated carbon products, whose degree of activation, impregnation, and granulometry are perfectly adapted to the specific demands of the armies of each country.

But most often, PICA teams develop a new carbon for every new project. This is, in effect, the best way to respond completely to the specifications of the project and to guarantee the best cartridge/carbon match.

  • The PICA approach:

    Do not rely on the density of a carbon to evaluate its effectiveness.

Whatever the application, a carbon's high density is not synonymous with greater adsorption and longer period of functionality. As such, a heavy gas mask cartridge will not necessarily be more effective than a light cartridge.

  • Nuclear risks:

Activated carbons are used in the majority of filters in ventilation systems of nuclear power plants in order to eliminate radioactive iodine compounds that might escape during an incident (leak). They are generally impregnated with iodine and a non-radioactive organic compound so that an "isotopic" exchange takes place: radioactive iodine takes the place of the non-radioactive iodine or compound.

  • The PICA approach:

Attention to the storage conditions of activated carbons

Activated carbons used in NBC protection are particularly sensitive to all types of contamination. It is also advisable to avoid storing them near organic solvents. Similarly, it is necessary to close activated carbon containers immediately after their use in cartridge- and filter manufacturing facilities.

There are several activated carbons of the PICA line of products that function according to this principle. With a coconut shell base, they have an average specific surface area of 1,000 m2/g.

The dedicated line of PICA products and services:

PICATOX