Fire and explosion
In the textile industry, nearly all materials being used are flammable to some degree.
What increases the risk of fire?
- Loose materials, eg fabric off-cuts or open layers of wadding – low density fibres burn very easily.
- Deposits of fluff and dust (fly) – dust on light fittings is a particular risk. Cotton fly is very hazardous when it is on fire, it is really difficult to put out because it is light and gets blown about by even light jets of water.
- Oily fibres, such as wool or cotton contaminated with oil from the spinning process.
- Rough, raw edges on rolls or bales – bales tend to burn on the surface and smoulder underneath – deep-seated smouldering in bales is almost impossible to put out from the outside.
- High piles of stock, especially if close together, can increase the speed at which a fire spreads.
- Traditional textiles mills, constructed using lots of wood and with the presence of fly, means that a fire can spread rapidly.
- Flammable liquids that ignite easily or oxidising agents that may make an existing fire more intense by fuelling it with oxygen.
What can you do to reduce the risk of fire?
- Practise good housekeeping – clean up fluff and dust regularly, especially high ledges
- Keep offcuts in bins, preferably metal
- Keep storage in workrooms to a minimum
- Use indirect workroom heating
- Limit smoking areas
- Control hot work – some fibres support smouldering and fires, so hot work should be stopped at least half an hour before the end of the day to make sure the risk has passed
- Don’t keep raw materials and finished goods on the ground floor where people are working above – materials and goods should be stored separately, eg in a different building or in another part of the factory with fire separation
Processes with high fire risk
- This involves the manufacture and storage of latex foam and rubber underlay and foam carpets. These can burn to produce enough smoke to classify the material as a highly flammable solid
- Traditional wool or nylon hessian-backed carpet is not particularly flammable
- A high level of sprinkler protection is needed where foam-backed carpets are stored
Opening and carding
- Foreign bodies in fibres and baled raw material can come into contact with rotating metal parts of machinery and produce sparks or frictional heat. Natural fibres are more likely to contain foreign bodies than synthetic fibre
- Opening rags is a vigorous process and it is highly likely that they will contain foreign bodies, such as coins and metal buttons that may cause a spark.
- The spread of fire from opening machinery through ducting can be high; the spread of fire through the fibre delivery and trash recovery systems is also fairly high risk. Automatic fire detection in a ducted system is essential.
Spinning and weaving
Ignition of fly:
- Traditional spinning causes deposits of fly and, if contaminated by oil – this can be particularly flammable
- Weaving – the main hazard is ignition of fly by electrical faults, usually insulation failures caused by mechanical vibration. Modern looms are less susceptible to vibration
Effective controls include good housekeeping and making sure you have good standards of electrical and machinery maintenance.
These are processes that alter the physical characteristics of the cloth, either by physical means, eg raising or milling, or chemical means, eg crease resistance.
Processes involving a naked flame, eg flame bonding can cause smouldering – keep flame‑bonded materials separate from the main store until the risk has passed.
Stenters used for thermal bonding are a common source of fires – smouldering in the finished reel of material can develop into a fire later. Also, if the material stops in the stenter, it is important that the heat supply is cut off automatically. Thermostats can fail, different materials need different temperatures and fires can result if the temperature setting has not been altered.
What can cause an explosion?
Wool dust can cause explosions. Good housekeeping is essential and LEV may be needed at carding machines to control dust.
Ground flock (rather than precision cut) from mainly cotton, acrylic and nylon fibres, gives a higher risk of explosion. If dispersed into the atmosphere, eg when cleaning down, it can cause an explosion and/or fire. Fibres settle quickly, so don’t turn gas burners on stenters on for ten minutes after the fans start.