We are well familiar with the role played by the textiles, clothing, and wears in relaxing the individual from comfortable and beautiful bedroom to the presentations made in sophisticated office environment. There is lot more potential in textile products in serving the diverse spheres and activities of human live, much is recognised through the advancement achieved in technical textiles. Textiles are no longer the matter of bedroom and fashion.


Tent is one of the textile- based products where functional attributes of substrate are significantly important in meeting the varying conditions of climate and usage. People are familiar with the camping- type temporary usage of tent, however an extra- ordinary application could be seen in natural or warfare disaster, when sheltering has high importance.

History has shown the use of tent almost in all parts of world. Primarily they were desired to provide shelter against the natural forces of sunlight, air, soiling, moisture, rain or heat wave, when used in camping, caravan- temporarily settling, desert journey, military campaign etc. The requirements for using in socio-cultural events, family celebrations and parties were more focused for aesthetics.

The technological advancement, over half a century, had turned the tent production a noted scientific profession. The important components of a tent include sheets of fabric (or other material) attached to a frame of poles. It is usually portable and may be attached to ground using ropes (guy lines) and stakes. Modern tents are required to possess several functional properties to resist the various climatic changes and possible harms. These mainly include flame retardancy, water proofing, breathability, moisture permeability and its weight.

The inner of tent comprises roof, walls, and sewn-in ground sheet (in selected cases). The structural support is provided by the poles, made of wood or metal or fibre glass, that may be flexible or rigid. The outer part is a water proof sheet, called fly sheet or rain fly, attached on top of the inner fabric. This water proof sheet may be of nylon or canvas and should be breathable. Fastening of tent to ground requires the use of stakes (pegs) to anchor the bottom edge of flysheet and inner fabric to ground.

Fairly simple appearing structure of tent had taken thousands of years to adopt the modern requirements, and a range of applications. From Arab world to American continent the production of tent had absorbed the innovations of art and science over several generations. Arabic word for tent is "Khayma". The street of tentmakers in Cairo, Shari Khayyamia" is known for the craft of making huge tent pavilions, called suradeq for hundreds of years. The tents for using in the travelling of King Abd al- Aziz were produced by the grand father of Emam Hamid, a tent maker in Cairo.

There are companies, for example, like Panther primitives and Denver Tent Company claimed to be in tent making since 19th century.


Figure 1: Basic structures of dining fly and dome tents.
Courtesy: http://en.wikipedia.org

Panther primitives made military tents for French and Indian War, Revolutionary War, War of 1812, and American civil war. Some of the camping and expedition tent manufacturers are shown in Table 1.

These days, the concept of using tent to prevent sunlight is too narrow to realise the requirements. The functional performance or the service rendered by the tent is mainly desired. However, this would vary depending upon the type. In terms of the "shape and design" it is relatively easy to know the conventional types. Simplest form of tent is dining fly made of a single rectangular sheet, with two opposite sides held in middle by metal poles. It is intended for storing material (equipment, device etc) and not for sheltering people (Figure 1). The various conventional types of tents are summarised in Table 2.

Symbolically, Arab history bears one of the oldest cultures of "living in tent". The desert Journeys, for trade, travel, etc, had been the visible part of Arabs. Every winter time, these days, thousands of Kuwaitis, Qataris, and Saudis leave comfortable home for desert relaxation in vast temporary tent cities.

Custom-built tent is particularly an attractive option for the user to buy a tent that offers him high value. There are companies who provide after-sale service including repair, tent cleaning, tent pole and frame metal fabrication and a large selection of tent accessories. In varying and severe climatic conditions, this service is particularly useful for places where tents are required to work for long duration (several weeks) and in huge quantity.

Renting tent would be a factor in cutting down the basic fixed cost needed to have large number of tents, and on temporary basis.

Table 2: Some conventional types of tents

An understanding of the functional aspects of tent is really viable in selecting the most appropriate type of tent. One such function is water proofing that means repellancy of water by the tent fabric. Rainfall may

produce a water entry pressure of around one pound per square inch (PSI). Over the period of hours or days a heavy rain fall may generate a pressure tens of times higher than 1 PSI. Many of the coated fabric may not withstand such pressure resulting in the likely collapse of tent. Waterproofing the fabric prevent any retention of water by the tent fabric, however, it is vitally important to know the durability of this proofing against the real climatic conditions.

It should be tested, preferably using the possible climatic conditions of camp area, with the help of the appropriate standard methods. There are several tests available for evaluating the water proofing of fabrics against the rain storm including Bundessmann, and WIRA shower tests.

Making the water proofing using coatings, would require knowing the resistance of coating against the flexural deterioration. The PTFE laminates out perform polyurethane in flex and wear test - where polyurethane loses more than 50% of its waterproofing.

Refurbishment, i.e. re- introducing the functional properties, of tent is also possible. One way is the application of coating like Mystox TRP (a thixotropic emulsion)- Catomance Technologies, however, this is particularly designed for military tents, and UK military forces are using it. Its coating can be applied to tent using roller or brush. This coating will regenerate water resistance, flame retardancy, rot resistance, and infra- red reflectance properties in tent.

Another important property of tent fabric is breathability - the ability to allow the movement (in and out) of air and gases through the porous fabric structure. It should also permit the moisture vapour inside the tent to pass out rather than to condensate on the walls. A human body in a tent gives off water vapours (it may be cup of water in an hour in some cases), however boiling water for cooking/ tea produces more vapours. Ventilation alone is not enough to prevent condensation. There are tent types that may provide adjustable control on the air movement in tent, enabling the tent to serve well in varying climatic conditions. One such example is the tent described in US patent 6,216,715 (inventor- Howe, Robert H). This contains an inner canopy having a window and a flysheet (outer canopy) spaced above. The fly sheet also has a window aligned to the inner canopy's window. Its overall structure can be adjusted to warm, cool, cold and precipitation conditions. It is relatively a multi- seasoned tent.

How serious is the breathability of tent! This may be imagined by a legal case filed in USA. A man with his son was out for camping, and used charcoal barbeque inside their tent for warming. The next morning, son woke up and found his father dead. Investigations using air flow test showed that the replacement model fabric was more breathable compared to the tent fabric in question. Monitoring tests on assessing the Carbon Monoxide (CO) levels generated by the smouldering barbeque were conducted separately in two models of tents. The questioned tent fabric showed 1000 ppm of CO in 10 minutes and maintained this level for an hour, i.e. 6000 ppm of CO per hour. However replacement fabric showed the figure of not more than 400 ppm of CO per hour. Toxicology literature indicated that 1000 ppm of CO for an hour was lethal to some people.

Although jury trial turned down the assertion of making the tent manufacturer liable for death. It is clear that smouldering charcoal could be lethal when used in tent; however the breathability of tent fabric may turn the situation more dangerous. This is particularly important to care for when a tent is used in cold season. Moreover, the simplest way of selecting the tent on the basis of size (i.e. number of persons to be accommodated) is not fully appropriate to meet protective requirements.

This article is dedicated to the volunteer's efforts aimed to assist the affected of earth quake, October 2005, in South Asia.