The textile industry can generally be divided into two manufacturing process; raw fiber to yarn production and yarn to finished garments production. Both types of textile manufacturing pose similar fire and property damage hazards.
Raw materials are generally received in the form of fibers or yarn, followed by fabric production that involves knitting and weaving. Pre-treatment is completed after fabric production and can consist of washing, de-sizing, scouring, and bleaching (pre-treatment can be completed on raw materials as well). After treatment, dyeing, re-dyeing, and printing are completed. Finished-treatment is completed for crease resistance, antistatic treatment, anti-piling, and water repellents. The final process includes cutting, sewing and the addition of buttons, zippers, etc.
The main hazards involved with textile manufacturing is the accumulation of combustible dust, lint, or fluff in concealed spaces such as within duct systems, enclosed spaces, enclosed systems, and equipment resulting in high intensity fires that can easily spread. The risks involved with textile manufacturing significantly increases when operations involving the use of solvents or other ignitable liquids takes place on site such as pre-treatment, finishing operating, dyeing and/or printing. If the textile manufacturing occupancy is identified to be high risk all recommendations regarding operations and protections should be followed as per recognized standards. Also, consideration should be given to separating high combustible loading areas such as raw material storage and finished goods storage from high-risk process areas. Human element is crucial in textile manufacturing as an effective housekeeping and preventive maintenance program can significantly reduce the risks and business interruption.
Older textile mills tend to be multi-story buildings constructed on timber floors and roofs with brick exterior walls. Increased building heights impose various hazards, e.g., firefighting difficulty, storage of raw materials and finished goods, staircases, lifts, and chutes acting as flues, high speed machinery on upper floors. Modern mills tend to be pre-engineered or noncombustible construction. Concealed spaces can be found in the floors, walls, and ceilings, which can accumulate combustible dust. Floor penetrations are also common and in the event of a fire can result in increased water and smoke damage.
Ideally raw materials and finished goods storage should be separated from process and production areas by providing fire resistive partitions with approved automatic closing doors (FM Global Property Loss Prevention Data Sheet (FMDS) 7-1, Fire Protection for Textile Mills, recommends 1 hour rated fire partitions). Floors should be water resistant above valuable storage or sensitive high valued equipment. When installing HVAC, easy access to ducts (including underfloor ducts) and tunnels for regular housekeeping should be provided. Ducts should have smooth epoxy coating to reduce lint build up. Enough stock filter media should be stored onsite to recover the largest filter. Always filter all return air through a filter media capable of removing fine particles of lint before the air enters the duct system.
Ventilation is another major concern for the textile industry as mills and manufacturing floors can be large. Return air system are critical for collecting dirt, fluff, lint, and other flying matter, but poses a serious risk as all air ducts and collection systems are normally full of such refuses. Raw material bales of fiber (raw yarn) contain impurities, and in spite of magnets being provided in the most machines, iron particles can cause a spark due to mechanical friction. Dust chimneys and blow room cellars are hazardous in natural as all dirt, fluff and lint are accumulated here and exhausted therefrom.
Carding, Spinning and Weaving machines are susceptible to fire due to friction between cylinders, casings, belts, straps, and pulleys. Frames can easily accumulate dust in the form of lint or fluff. Overheated equipment parts (e.g., bearings) can ignite accumulated lint or fluff. If heddles are used in the weaving stage, varnished chords (highly flammable) can be present; this can be avoided by using metal heddles.
In general, automatic sprinklers should be installed in all areas including concealed spaces. Textile plant production areas should meet the minimum NFPA protection standards with design areas of 0.15 gpm / sq. ft. using automatic sprinklers of any temperature rating for an area of 2,500 sq. ft. (wet-pipe) or 3,500 sq. ft. (dry-pipe). Water supply shall be adequate for 2 hr. capable of meeting the sprinkler discharge flow rate plus 250 gpm for hose streams. Equipment containing fibers shielded from over automatic fire sprinklers should have Ordinary Hazard pipe schedule on 100 sq. ft. spacing. If areas are shielded by vertical partitions additional sprinkler heads are needed. Automatic sprinklers should be ½ in. orifice with a temperature rating of 165°F.
FMDS 7-1 should be used for various equipment and process areas found in the textile industry. Special protection (dry chemical or gaseous agent) should be installed on all enclosed processing equipment to discharge into the equipment downstream of detectors. Automatic shutdown should be installed on all equipment to prevent fire spread.
Housekeeping is a critical component to reduce fire and explosion as a result of dust, lint and fiber accumulation. The established housekeeping policy should include a routine schedule for cleaning of the floors, walls, ceiling, supply and return air ventilation systems. As a general rule, the maximum tolerable deposit thickness for loose fluffy lint is ½ in. over a maximum of 500 sq. ft., likewise limit dense deposits to ¼ in. and oil saturated deposits to ⅛ in. An established maintenance program should be cover general electrical system maintenance as well as include annual IR inspections.
Overall superior administration of management programs is critical to prevent large losses. Risk Logic can recommend and help develop preventive maintenance and property loss control programs at your facility. Please contact us to schedule a property survey at your facility by one of our engineering specialists.
References include but are not limited:
|FM Global||FMDS 2-0: Installation Guidelines for Automatic Sprinklers|
FMDS 5-1: Electrical Equipment in Hazardous (Classified) Locations
FMDS 5-20: Electrical Testing
FMDS 6-9: Industrial Ovens and Dryers
FMDS 7-1: Fire Protection for Textile Mills
FMDS 7-29: Ignitable Liquid Storage in Portable Containers
FMDS 7-32: Ignitable Liquid Operations
FMDS 7-76: Prevention and Mitigation of Combustible Dust Explosion and Fire
FMDS 7-78: Industrial Exhaust Systems
FMDS 7-84: Hydrogen Peroxide
FMDS 7-99: Heat Transfer By Organic and Synthetic Fluids
FMDS 8-7: Baled Fiber Storage
FMDS 8-9: Storage of Class 1, 2, 3, 4 and Plastic Commodities
FMDS 8-18: Storage of Hanging Garments
FMDS 8-23: Rolled Nonwoven Fabric Storage
FMDS 8-30: Storage of Carpets
|NFPA||NFPA 13: Standard for the Installation of Sprinkler Systems|
NFPA 30: Flammable and Combustible Liquids Code
NFPA 68: Standard on Explosion Protection by Deflagration Venting
NFPA 69: Standard on Explosion Prevention Systems
NFPA 70: National Electrical Code