quality control and needle managment

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Quality Control & Needle ManagementBuilding An Effective Programme

1. Introduction

2. Retailer Requirements

2.1. Concept of Due Diligence

2.2. Metal Detection

3. Risk Mitigation Through Good Working Practices

3.1. Needle Control Programme

3.2. Needle Detection

3.3. Keeping Records

3.4. Needle Audit

4. Summary

5. Literature References

2 White Paper METTLER TOLEDO

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aper 1 Introduction

A series of incidents in the early 1990's including children receiving scratches from broken needles in clothing, a sportsman hurting his foot on a staple buried in a trainer and others alerted many retailers to the hidden dan-gers of metal contamination.

Hence, it has become the responsibility of the manufacturers, of textiles, apparel, soft toys and in fact, of any item of sewn product likely to be in next-to-skin contact, to take every precaution to ensure that their products are safe, free from contamination and not likely to harm the end user in any way. In these litigious times, it is in the best interests of all manufacturers to take steps to ensure they have systems and procedures in place to mi-nimise the risks and, in the event of a claim, have the necessary procedures in place and documentation avail-able, to prove they have been diligent in their manufacturing process to the best of their ability.

Are you confident that your systems and procedures will stand up to scrutiny?

1.1 Types of Metal Contamination and their Consequences

Metal contamination can be introduced inadvertently into textile products in several ways, for instance:

• Needles,needlefragments,pinsandstaplesfromthemanufacturingandsewingprocesses• Tools,e.g.knives,scissors• Hardwarefrommachinery,e.g.nuts,bolts,screwsetc…• Personaleffectsorjewelleryparts

If present, metal contamination can have serious consequences for:

• Consumers:-injuryfromaneedlefragment,inworstcasemayleadtotransmissionofbloodborne viral infection

• Retailers:- potential legal claims from affected consumers; product recall to ensure that other customers are not similarly harmed; cumulative costs of recall, litigation and reparations; loss of brand reputation

• Manufacturers:- retailers may impose mandatory fines and could terminate the supply contract. This could lead to factory closure if the business is largely reliant upon that single retailer.

2 Retailer Requirements

As stated above, potentially serious consequences may result if a broken needle tip is left behind in a garment. Hence, to protect their own position, retailers make it mandatory that their suppliers take a range of steps to en-sure their products are free of metal contaminants. The concept of "Due Diligence" is frequently an integral part of these requirements.

2.1 Concept of "Due Diligence"

Product Liability Law prohibits manufacturers and retailers from placing non-compliant products on the market. In such cases it is not a sufficient defence to claim that you did not intend to do wrong or were unaware of the re-quirements. The fact that you have contravened the law can be sufficient to provide a court with grounds to convict.

3White Paper METTLER TOLEDO

The Due Diligence defence is available to manufacturers accused of a breach of regulations. Essentially, the defence is that the "accused" took all reasonable practicable steps to avoid the breach. Therefore, those charged need to prove that:

• allreasonableprecautionsweretaken;• theyexercisedallduediligencetoavoidtheoccurrence,whetherpersonallyorbyanypersonundertheir

control.

"Taking all reasonable precautions" includes setting up systems and controls which are appropriate to the risk. What is reasonable is determined by the size and resources of the business. "Exercising all due diligence" in-volves having procedures in place which review and audit the system to ensure it is operating effectively in order to avoid placing contaminated product on the market.

Whether or not a defence will be successful depends on the circumstances surrounding each case. Doing noth-ing is not an option!

This legal concept informs the QA policy of the Retailers who may require their suppliers to put in place mea-sures to ensure, if a claim were to arise, that documentary evidence exists to show that due diligence has been applied.

In apparel manufacture, use of a Metal Detector within a comprehensive Product Safety policy would usually form part of a 'Due Diligence' defence.

2.2 Metal Detection

Whilst their use in sewn product sector is relatively new, industrial metal detectors have been available for well over sixty years. With designs optimised according to applications, there are many different kinds available.For textiles, in particular sewn product like apparel, home furnishings and foot wear, a stand-alone conveyor type metal detector is most suited where, upon detecting metal contamination it should stop the conveyor and raise an alarm.

2.2.1 Compatibility of Sewn Product with Metal Detection:

A conventional metal detector is designed to detect all kinds of metal. Therefore it will serve as a suitable scan-ning device for any product which is free from metallic accessories and embellishments.

Consequently, a conventional metal detector is not designed for scanning products which intentionally contains metalparts,forexamplezipsandpoppersinclothing,whichwillallberejectedbythedetectoreverytime. To cater for sewn product carrying metal accessories a 'needle detector' must be used. This is a special kind of a metal detector which is able to ignore 'non-ferrous' metal and at the same time detect 'ferrous' metal. Therefore, as long as the zippers and snaps are made from non-ferrous metal, they will pass through the machine unde-tected. And since needles are always made from ferrous metal, these should remain detectable.

Retailers will often nominate manufacturers who can supply metal detection compatible accessories.

As long as the main target contaminant is broken needles and other ferrous metal, a needle detector can be used for products with or without metal accessories.


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aper A natural consequence of ferrous-only metal detection is that the rest of the product, inclusive of fabric and any

point-of-sale packaging included, must be free of any ferrous content in order to be fully compatible with needle detection. A product can have a magnetic profile, or a 'Product Effect', inadvertently acquired through the manu-facturing process and may be due, but not limited to:

• moisturecontent• ferrous-baseddyestuff• fabrictreatment• mineralresiduefromstonewashorfabricabradingprocess• recycledpackaging

This unpredictable 'product effect signal' can add or subtract randomly from the target contaminant and compro-mise needle detector sensitivity performance.

It is therefore always recommended, that before implementing metal detection, samples of complete product be tested in a metal or needle detector to confirm compatibility.

2.2.2 Detection Sensitivity Standard

Each metal detector is designed to achieve a specific sensitivity level. Metal fragments smaller than this defined sensitivity level may not be identified by the detector, hence it is important to select a metal detector which is sufficiently sensitive to meet the Retailers' requirements, expressed as sizes of ferrous metal spheres, of either 1.2mm or 1.0mm diameter. The test balls should be precision made ball bearings of specified Chrome steel (fer-rous) composition conforming to AISI 52100 (or EN31) standards.

As metal detection is an electro-magnetic phenomenon the sensitivity decreases as the tunnel/aperture size of the metal detector increases. Therefore the ability to achieve the retailer specified sensitivity is limited by aperture sizes available.

Orientation Effect: A metallic sphere has a constant shape whichever way it is presented to a metal detector and therefore always produces the same amount of signal when passing at the same location. All other metallic shapes, be they ferrous or non-ferrous, produce a signal which is dependent upon metal type, its shape and orientation and could vary considerably in its amplitude. For example, a few millimetre long needle fragment can produce a signal up to ten time smaller when passing lengthways through the needle detector compared to widthways.

Hence metal spheres are used as a standard to determine a detector's capabilities and to enable comparisons. Sensitivity is defined as the smallest diameter ferrous metal sphere which is always detected, even at the point of least sensitivity within the metal detector aperture.

The most widely accepted and enduring detection standard is 1.2mm, followed by 1.0mm diameter ferrous test ball.Thisisempiricallycalculatedtobejustalittlesmallerinitsmagneticequivalencetoatypicalneedlefrag-ment which has broken off at the threading point at the sharp end, and is passing through a needle detector at point of least sensitivity, in its worst detectable orientation.

Point (or area) of least sensitivity inside the detection tunnel vary widely according to the design of the detector 'head' and how the magnetic and detection elements are arranged around the aperture, through which the prod-uct to be scanned passes.

2.2.3 Record Keeping to Show Due Diligence

A Due Diligence defence against metal contamination requires the manufacturer to demonstrate that he has taken all reasonable precautions against the possibility of metal fragments leaving the factory in his textile products. Only through comprehensive Record Keeping can this be demonstrated.


A typical set of records, required to be completed and kept by the manufacturer, might include:

• MetalDetectorCalibrationRecord,showingthatregulartestinghasbeenundertaken• MetalDetectedProductLog,perday/pershift/perbatch• HandSewingNeedleControlRecord• BrokenNeedleRecord• RecordofMetalContaminantsDetected

In their most basic form, records may be hand written, but they are prone to human error, their veracity may be questioned, and can take up a lot of management time. Electronic data capture, available with modern metal de-tection systems, can help increase accuracy and therefore credibility as well as saving management time. In the most advanced machines it is possible to store production and diligence data in encrypted form. As these data can be stored within the machine over longer periods of time it enables the Retailers to verify independently that each of their orders has passed through a metal detector before being shipped.

2.2.4 Implications of Vendor Non-Compliance

Product liability legislation exists in many countries to protect consumers from unsafe products, and has a very wide scope.

Independent watchdogs such as the U.S. Consumer Product Safety Commission are charged with protecting the publicfromunreasonableriskofseriousinjuryordeathfromthousandsoftypesofconsumerproducts.Withapar-ticular remit for child safety, they monitor products which pose a fire, electrical, chemical, or mechanical hazard.

Manufacturers of sewn products are already prohibited from using metal accessories containing nickel or lead paint. Fabrics used must meet minimum flammability ratings and children's products must be designed so that nothingcancausechokingorstrangulationhazard.Sharpobjectssuchaspins,staplesandbrokenneedlefrag-ments hidden within, pose one of the most routine risks a supplier must work to eliminate to avoid a product recall.

In forming contracts for the supply of products to them, retailers will seek to pass down the responsibility for productsafetytotheirsuppliers.Aspartofthosecontracts,manyofthemajorRetailershavedrawnuptechnicalmanuals which define not only the physical aspects of the products to be supplied, but also the Product Safety regime under which those products are to be manufactured. As a deterrent against poor performance, and to reduce the cost to the Retailer of consumer claim, the contract may specify that at every incident a fine will be imposed on the manufacturer. The fine can be heavy and can start from US$20,000, and may escalate if the incident results in product recall, reparation payments to the consumers and legal costs.

Manufacturers are likely to hold Product and Public Liability Insurances to cover against claims arising from the consequencesoftheirunsafeproductswhichcauseinjurytotheconsumer.Havingmetalcontaminationandother quality control measures in place would help to reduce insurance costs as well as prevent such claims from arising in the first place.

In the worst case, manufacturers who fail to control needle contamination at source and are persistent offenders may find their supply contract terminated, which might have profound implications if their business largely de-pends upon one large buyer.

All reputable retailers conduct detailed factory audits in advance of placing any business with a new vendor. Included in these audits is an assessment of their capability to control metal contamination. Without proper sys-tems in place a vendor is unlikely to win new business nowadays.


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aper 3. Risk Mitigation Through Good Working Practices

In a fast moving and highly automated manufacturing environment such as food and pharmaceutical manufac-ture, where public health is of highest concern, a most rigorous approach is taken by applying internationally recognised principles of Hazard Analysis and Critical Control Points (written HACCP, pronounced "hassup"), in order to ensure utmost product safety.

Whilst this would be seen as over burdensome in the textile and sewn product manufacturing context, the basic principles it embodies can be used easily as a guiding template to implement an effective Needle Control Policy to suit every individual circumstance.

Adherence to good working practices will always ensure that risks of metal contamination are minimised. These require no more than a thorough understanding of one's manufacturing and product handling process and a common sense approach to risk analysis and product safety. These are likely to feature:

• ImplementingaNeedleControlProgrammetoremoveandisolatebrokenneedlesasearlyinthemanu-facturing process as possible

• Usingametal/needledetectorwithintheNeedleControlProgramme,tobethefinalgatewaytoshippingproduct safe from broken needles

• Ensuringproductsaremetaldetectioncompatible.Itpaystothinkahead,rightattheproductdesignor sampling stage. Check both, product components - fabric, accessories, fasteners, interlining, filling included - as well as the process materials, are suitable for metal detection. Ultimately product must be capable of passing a metal detector without causing false alarm. If unsure, contact the metal detector manufacturer to get the product tested

• Identifyingtheoptimumlocationtocarryoutmetaldetection• AppointingaseniormemberofthemanagementteamtobeinoverallchargeoftheNeedleControlPolicy

and nominating a senior member of the quality assurance staff to be the metal detection champion • Keepingallpersonnelinvolvedintheneedlecontrolandmetaldetectionprocessfullytrainedbothonthe

procedures and the equipment• Creatingawarenesswithinthewholeorganisationoftheimportanceandnecessityofthisaspectofqual-

ity control• Conductingperiodicreviews,inlightofcumulativeexperience,oftheeffectivenessoftheneedlecontrol

programme and feeding back into the process

3.1 Needle Control Programme

For any manufacturing process, textile, leather or otherwise, which involves sewing needles, and the end product is likely to be in next-to-skin human contact, a Needle Control Programme must be implemented. This should include Basic Needle Control and recommended procedures concerning the use of pins, staples and tools in manufacture, together with special rules for hand sewing.

3.1.1 Basic Needle Control

This may be summarised as follows:

When a needle breaks:

• Thewholearea,includingalladjacentworkstationsmustbesearchedinordertofindallpartsofthebro-ken needle

• Allneedlepartsrecoveredmustbeattached/recordedonaneedlecontrolsheet• Ifanypartsofthebrokenneedlecannotbefound,thesurroundingworkpiecesmustberemovedand

passed through a metal detector in order to isolate the missing fragments• Ifallpartsstillcannotbefound,thenthoseworkitemssuspectedtocontainapieceofbrokenneedle

must be taken out of production and destroyed


Spare needles:

• Nomachinistmustbeallowedtoholdspareneedles• Allspareneedlesmustbesecurelystoredundersupervision• Onlyauthorisedstaffmayissueanewneedle• Newneedlesmustonlybeexchangedeitherwithaworn,orwithallpartsofabrokenneedle

Record Keeping:

In addition to having a documented Broken Needle Policy, the following data must be captured throughout the production process:-

• Needle Incident Log: Records all instances whenever a needle breakage occurs by time, date line, style and customer batch order

• Broken Needle Record: Attempts to recover the needle; as above but with broken needle fragments found and pieced together with tape, to recreate the whole

• Metal Detection Log: Records all quantities of sewn product processed through each metal detector, by line number, style and customer order etc.

• Metal Detection Calibration Log: Periodic checks must be performed every day on the metal detector, and results recorded to confirm machine was working before, during and after each batch of product was passed through it.

• MetalDetectorMaintenanceRecords• Personnel Training Record: List of responsible people who have received training in needle control pro-

cedures and needle detection• Recordsshouldberetainedforaminimumperiodwhichmustbethelongerofthefollowingtwo:

o as agreed with the buyer-retailero commensurate with legal requirements relevant to defending a product liability claim arising in

the territory where the product is sold

3.1.2 Pins, Staples and Tools

Needles are not the only form of metal contamination that can be introduced into sewn products. To further reduce the risk of metal contamination:

• Nosettingpinsorstaplesshouldbeallowedintheworkingareas• Anyhandtools,forcuttinge.g.scissorsandknives,Kimblegunsfortaggingandanyothersusedinpro-

duction must be attached to the workstation• Productionworkersmustnotbeallowedtostoreanytoolsormachinesparepartsinthesewingma-

chine drawers

3.1.3 Jewellery

Withtheexceptionofweddingbandsperhaps,wearingofitemsofjewellerymustbecontrolledinallproductionareas and where product is handled in the finishing sections.

3.1.4 Hand Sewing

Additional rules apply to hand sewing because of the additional risks involved:

• Handsewingshouldonlybeusedwhereanautomatedsolutionisnotfeasible,andinchildren'sgar-ments should be used by exception only

• Theretailermustbemadeawareoftheextentofintendedhandsewingoperationasearlyaspossibleduring product development and their agreement sought

• Replacementofbrokenorwornneedlesmustfollowthe'oneinandoneout'needledistributionmethodas per the existing Broken Needle Control procedures

• Onlyalimitednumberofworkersbeauthorisedforhandsewinginadesignatedquarantinedhandsewingarea


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aper • Handsewingneedlesmustremaininthiscontrolledareaatalltimes,andnowhereelseinthefactory

• Allhandsewingneedlesmustbeheldbythelinesupervisor,issuedatthebeginningofeachshiftandthen collected at the end

• Writtenrecordsmustbemaintainedforallproductprocessedinthisway,bystyleandcustomerorderand incidents of any broken needle recorded as per the Needle Incident Log

• Allproductmustbemetaldetectedonceallmanufacturinganfinishingoperationshavecompleted

3.2 Needle Detection

3.2.1 Types of Equipment Available

Static table-top and hand-held needle detectors can perform a useful function for occasional use. However, it is the conveyorised metal detector which has come to be recognised as the instrument of choice for any volume production environment.

Functionally all conveyor type metal detectors appear to look the same – a metal box with a rectangular aperture 'cut' into its body with a belt running through it, is mounted on a frame. Sewn product to be inspected is carried on the conveyor belt through the detection aperture where, due to the presence of a magnetic field, metal detec-tion takes place.

But that is where the similarity ends as, under the bonnet so to speak, there are many differences which exist be-tween makes and models offered by an ever growing number of manufacturers. Given that there can be a large trade-off between performance and price, it pays to be able to differentiate between the technologies available.Detailedexpositionofthevarioustypesofmachinesisasubjectforanotherwhitepaper.Adistinctionbetween'metal' and 'needle' detectors has already been drawn earlier. Essentially there are three 'generations' of needle detectors each improving upon and superseding the last - briefly:

• 1st generation – this is the earliest type of needle detector; uses a strong permanent magnet to create a static magnetic field. This is placed either above or below the conveyor and a detection coil is mounted on the opposite side. A piece of ferrous metal passing through this arrangement induces a signal propor-tionatetoitssizeandproximitytothedetectioncoil.Thesignaliscomparedtoanadjustabledetectionlevel – usually in an analog circuit - and if greater, causes the conveyor to stop and raise an alarm.

Within this category, variants exist which use two detectors in tandem, mounted on a common conveyor frame. The second detector is at a shallow angle to the first so that by taking advantage of the 'orienta-tion effect' it can detect a needle fragment which may have been missed by the first. This is a weakness inherent in a single-sided magnet-coil design. It is worth noting that there is no overall gain in sensitivity specification, measured using a ferrous test ball.

• 2nd generation – Based on a much more advanced 'balanced-coil' principle, a heavy band of copper wire is wrapped 360 degrees around the detection aperture, like an MRI scanner, through which the product passes. The coil is energised with a very low frequency current to create an alternating electro-magnetic field. A pair of detection coils is mounted above and below the conveyor, connected in a 'bal-anced bridge' configuration. Signals picked up as the product passes through this 3-coil arrangement are converted into ferrous and non-ferrous categories using 'phase discrimination' techniques and real-time software algorithms. The machine can be 'taught' to recognise non-ferrous and therefore to ignore it, or cause a detection event upon finding ferrous metal.

• 3rd generation – In a fundamental redesign of the 'balanced-coil' system key needle detection perfor-mance parameters have been raised significantly to give higher sensitivity to ferrous contamination and greater tolerance to non-ferrous metal. Stability of performance is assured through an EMC compatible de-sign which is immune to electromagnetic noise from other equipment as well as line voltage fluctuations.


Metal and 'foreign body' detection technology based on x-rays has existed in the food, pharmaceutical and other process industries for some time. Real time x-ray image processing software can be 'trained' to identify all types of contaminants including broken needles within a sewn product. Whilst cost remains the main barrier to its widespread use, in cases where conventional needle detectors cannot work, for example where there is large inherent ferrous-like 'product effect' that can't be eliminated by process improvement. X-ray may remain the only option available.

3.2.2 Basic Characteristics of a Needle Detector

Whichever generation machine is used, in order to provide best due diligence it should

• haveanaperturesizechosenoptimallyfortheindividualproductstobeinspected• performinastableandconsistentmannersidebyside,asmaybenecessary,incloseproximityto

other production and factory equipment which may cause electromagnetic interference• becapableofdetectingtheminimumtestballsizeasdeterminedbythebuyerneedlecontrolpolicy

within the fabric of the product together with any metal accessories including final packaging

3.2.3 Operation Supervision

It is essential that a nominated individual be made responsible, e.g. the Production/Shift or Quality Control Man-ager. The duties should include:

• Retainingthekeythatenablesthedetectortobere-setfollowingacontaminationalarm.Thisistoensurecorrectprocedureshavebeenfollowedtodealwiththerejecteditemandtoavoidunauthorisedre-start-ing of the machine.

• Undertakingregularcalibrationchecksonthedetector• Ensuringallpersonnelinvolvedinworkingwiththedetectorreceivepropertraininginitsfunctionand

use as well as needle control procedures• Maintainingandstoringalldocumentationrelatingtothecalibration,maintenanceandoperationofthe

detector and making them available for inspection and audit

3.2.4 Equipment Positioning

Anidealplacetolocateametaldetectorwouldbejustpasttheendofallsewingandfinishingstages.Themetaldetector should become the final operation itself as the products passes through it into a secure packing area, as shown in the diagram below.

Production

Area

Metal

Detection

Area

Quarantine

Area

Lockable

Reject

Bin

Needle Detector

Packing

and

Shipping

Wall

Fig-1: A Typical Needle Detection Inspection Layout

In this 'airport style' security measure the metal detector aperture creates the only route for the product to pass through the wall from one zone to the other.


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aper As an 'end-of-line' operation, each individual item should be presented to the metal detector either in the final

packaging as floor-ready merchandise, or at least in a polythene bag wrapping. This is to eliminate the risk of re-contamination if the items were scanned loose and unwrapped.

Anytimethedetectorrejectsanitemtheconveyorstopsandanalarmissounded.Theitemwhichisjustoutofthe detector aperture on the out-feed side is deemed to be the one to have caused the alarm and therefore con-taminated.Howeveritisgoodpracticetosweepallitemsontheconveyoratthattimeintotherejectbin,beforere-startingthescanningprocess.Thiswayitemsintherejectbincanbedealtwithmoreefficientlyasaseparateprocess once all the production batch has been scanned for shipment.

DiagramFig-1assumesthatthemetaldetectorhasa'stop-and-alarm'typerejectmechanism,whichistypicallyfittedto2ndand3rdgenerationmachines,hencethepositioningoftherejectbintotherighthandsideofthewall in the area labelled 'Quarantine'.

Incaseofa'beltreturn'mechanism,typicallyfoundinthe1stgenerationtechnology,therejectbinwouldhaveto be placed to the left hand side of the wall within the Metal Detection area.

Other product inspection schemes: Depending on the code of practice implemented by a retail buyer, different needle detection layouts may be required. These may involve using twin-headed detectors, or two individual machines placed at right angles to each other where the garment after passing through the first one is flipped over and then passed through the second. This scheme mitigates for the inherent weakness of the one-sided coil geometry to ensure any needle fragment if missed by the first is picked up by the second unit.

Clearly, any scheme requiring more than one machine will be costlier and will require more physical space. Given that the detection sensitivity of a balanced-coil machine is defined with much greater precision and no such weak areas, only the simplest layout as indicated in Fig-1 is necessary to meet the same level of due-diligence.

Through-put rates:Choiceoftherejectmechanismcansignificantlyaffecttherateatwhichitemscanbescanned through a needle detector. In order to avoid product spillage off the conveyor when the belt return oper-ates causing mix-ups, each item must traverse the full length of the conveyor before the next item can be placed. This limitation does not apply to the simpler stop-and-alarm system. For a comparable product size, conveyor length and speed, hourly through-put up to 5 times greater can be achieved.

3.2.5 Equipment Testing

Once the detector has been installed by the supplier, it becomes the user's responsibility to confirm that the metal detector continues to function to the required specification. These calibration checks should be undertaken each day when the machine is switched on:

• beforethestartofproductscanning-atthebeginningofeverynewbatch• atleastonceduringthebatch-ormoreatregularintervals• attheendofthebatch-justbeforeswitchingoff

It is only by testing regularly, can one be confident that the metal detector had maintained its detection sensitiv-ity, and had not developed any faults throughout the production period.

Given that different types of metal detectors exist with variants thereof, a '9-point' calibration test method has been devised to have a consistent scheme available by which performance of any type can be checked. Whilst it is essential for the 1st generation, only 1-point checking - through the middle (or 3 middle points if desired) - is needed for machines belonging to 3nd or 2rd generation.


3.2.6 Operating a 'Quarantine'

All items of product, which have passed through the metal detector should be collected and held back in a 'Quarantine' area until the next calibration check has been made. This is to make sure that the machine had not developed any faults during this period and had maintained it's normal function. Only upon the following test be-ing successful, should the product be released for despatch.

If a detector fails a calibration check, then all products collecting in the quarantine area since the last successful check should be returned to the metal detection area. The metal detector should be serviced to fix the fault and the product rescanned.

This ensures 'Positive Release' of stock from metal detection to a quarantined dispatch area in accordance with quality management policies common to many retailers worldwide.

3.3 Keeping Records

When called upon to demonstrate 'due diligence', well maintained and accurate records are vital. As discussed earlier producing these should be the responsibility of a nominated person e.g. the shift supervisor. At a mini-mum, information captured regarding the needle detection process for the items of product scanned should include:

• Date/time• Operatorname• Machine/linenumber• Purchaseordernumber• Customername• Styleandcolour• Numberofitemsscanned• Numberofitemspassed• Numberoffailures• Reasonforfailuree.g.

o Contaminant type (all pieces should be pieced together)o False Alarmo Non-compliant Accessoryo Product Effect

• Suppliername• Supervisor'ssignature

This should be done on a batch by batch, or production shift basis, for every order shipped, and allow traceability.

3.4 Needle Audit

A measure of a good quality management program is that it has procedures built in to monitor it's own effective-ness. By conducting periodic reviews, it can be established whether the needle management program is doing what it was designed to do, that it is being successful in ensuring production of a safe product.


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aper As part of this monitoring process it is recommended that the following questions be asked periodically:

1. The number of needles purchased?2. The number of needles distributed?3. The number of worn needles returned?4. The number of broken needles returned?5. The number of needle fragments found by detector?6. The number of missing needle fragments?7. Number of needle 'incidents' or claims

In an ideal world the figures in 2, 3 and 4 above should sum to be the same as in 1, and the answer to ques-tions 6 and 7 would be zero!

4 Summary

The introduction of a Needle Management Programme will improve the efficiency of a sewn product manufactur-ing operation through reduction in the risk of contaminants being present in finished products. Typical impact of a Needle Management Programme may be summarised as follows:

Before After

No proper needle control policy:• Veryfewbrokenneedlesarepickedupearlyin

the process• Totalrelianceontheneedledetectoratthelast

stage of the process• Highvolumesofwasteproduct• Panicmeasuresandcornerscuttoavoidship-

ment delays• Nomeansofprovingduediligenceintheevent

of a claim• Highriskstrategy!

Needle detector used as an effective tool in the quality process chain:

• Goodneedlecontrolandmanagementensuresearly removal of most contamination

• Needledetectionisthefinalsafeguardtoship-ping textile products which are free of metal contamination

• Abilitytodemonstratemeasurestakentoeradi-cate metal contamination, and mount a dili-gence defense

5 Literature References

Reduction of Metal Contamination: Building an Effective Programme, 2007. METTLER TOLEDO Safeline Limited.http://www.mt.com/mdguide

TescoClothingTechnicalManual–March2009:Version1

Quality Management Systems – Requirements. International Organisation for Standardisation, Geneva.

US Recall News – website URL: http://www.usrecallnews.com/

U.S. Consumer Product Safety Commission – website URL: http://www.cpsc.gov/


Disclaimer

No part of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, for any purpose without the express written permission of METTLER TOLEDO Safeline Limited.

This documentation is furnished with restricted rights.

The information contained in this manual is provided to assist producers in developing and implementing an effective needle control and detection programme. METTLER TOLEDO Safeline Limited does not warrant the accuracy or applicability of the informationcontainedhereinandassuchisspecificallynotresponsibleforpropertydamageand/orpersonalinjury,directorindirect for damages and/or failures which may be caused as a result of the information provided.

Mettler-Toledo Safeline Limited.Montford Street,Salford,M50 2XD,UK.

Tel: +44(0) 161 848 8636Fax: +44(0) 161 848 8595E-mail: [email protected]

Subjecttotechnicalchanges© 03/11 Mettler-Toledo Safeline LimitedPrinted in the UKSLMD-UK-WP-EN-YDS-QC-0311 (M)

For more informationwww.mt.com/needledetection

quality control and needle managment

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