Protective clothing against chemical and biological agents

Citation

Stylios, G.K. (2007), "Protective clothing against chemical and biological agents", International Journal of Clothing Science and Technology, Vol. 19 No. 2. https://doi.org/10.1108/ijcst.2007.05819baa.001

Protective clothing against chemical and biological agents

It may be ironic that our ancestors invented clothing to fulfil the basic need for protection against the environment and that in the recent past this function became less important to the extent that nowadays people are used to wear clothes as fashionable statements. The aesthetic became more important than the protective function. This is history, as they say – but is it?.

Well history repeats itself and events of recent years are very much re-visiting the question of this clothing function. It is recognised that the general public may need to be protected from chemical and/or biological agents and that clothing has to resist such dangers that could even be generated from environmental changes. I have therefore put some thoughts together to stimulate debate, thinking or indeed to encourage papers from possible researchers in this area.

Protection against airborne chemical and biological (CB) agents requires barrier materials that will stop the agents from contacting the human body while enabling the skin to “breathe”. The flow of CB agents through textile materials is complex, particularly in multilayer systems, which are typical of protective clothing.

To optimise the combination of the layers and textile barrier properties, a CFD approach to the mass transfer of the fluid (gas) system through a porous media (textiles) may be needed. A solution of transport equations in order to determine diffusive and convective transport of gases/vapours and heat needs taking into account CB vapour and liquid sorption by fabrics, and the variable properties of various materials.

Systematic studies need to be undertaken of the effects of fibre properties, yarn and fabric construction and clothing assembly on the degree of protection offered, and the potential for interactive relationships between these parameters. Other key factors that also need to be considered are:

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  fabric adsorption, volume solid fraction of fabrics,

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  air permeability,

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  moisture vapour transmission,

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  thickness of the fabric,

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  viscosity and

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  concentration distribution of CB agent flow.

Modelling work may then be done starting from simplified representations of air flow over 2D single layer test beds using governing equations for mass, momentum and heat transfer in fluids to predict flow velocity, temperature, pressure and composition at each location within a 2D mesh. Computational representation of clothed humans can then be developed as the basis for assessing performance. Supporting the modelling work, experimental work will also need to be performed at each stage of the incremental modelling process.

This is a new and exiting area in our field and I welcome letters from authors, thoughts or papers that I will fast track in forthcoming issues of IJCST.

Finally a dedicated email address: ijcst@hw.ac.uk has been set up for receipt of your correspondence and papers. I look forward to hearing from you.

G.K. Stylios