3.5 Work Instructions & e-Records

Paper work instructions are a liability. They are static, easily defaced, and impossible to revoke instantlyinstantly. whenIf an Engineering Change Order (ECO) is released at 09:00, a criticalpaper-based engineeringfactory changeis occurs.still In a digital-first facility,building the Work"Old InstructionWay" (WI)at is10:00. notThe just a reference document; it is a context-aware control layer that dictates execution and captures the legal recordgoal of production.

Context-Aware DigitalElectronic Work Instructions (DWI)EWI) is not to "digitize the binder," but to synchronize the operator's visual field with the active BOM, Revision, and User Capability.

Station Control & Skill Enforcement

Before showing a single instruction, the system must validate the human at the screen. Access is a privilege, not a default state.

1. The Login Logic

Do not treatuse generic "Line 1" accounts. Every mouse click must trace to a legal identity.

• Mechanism: RFID Badge Scan or Biometric. (Typing passwords is too slow for the MESfloor).
• Timeout: terminalImplement as"Auto-Logout" on inactivity (e.g., 15 mins) to prevent "Ghost Records" where Operator B works under Operator A's login.

2. The Skill Matrix Gate (Certification Check)

Just because you can log in doesn't mean you can build.

• Logic: If Work_Order requires "Soldering Class 3" AND User_Skill ≠ "Soldering Class 3" → Then Block Station. Display: "Certification Missing."
• Expiry: If Certification_Date < Today → Then Block Station.
• Override: Requires Supervisor Badge scan to authorize a "Trainee Mode" (where the Supervisor accepts liability).

3. Shift Handover

Production is continuous; shifts are not.

• The "Hot Swap": Allow Operator B to scan in while Operator A is still logged in.
• Action: System closes Operator A’s session (End Timestamp) and starts Operator B’s session (Start Timestamp) instantly. No downtime.

The Architecture of EWI

Do not simply display a PDF reader.on Thea operatormonitor. shouldA neverPDF "search"is forpassive. instructions.An TheEWI system must pushbe Context-Aware and Interactive.

Context-Aware Display

The MES knows the exactWork page relevant toOrder, the specificUnit unitID, and station.the Routing Step. The screen must filter the content accordingly.

• Logic: If Unit = Variant A → Then Show Assembly Image A. Hide Image B.
• Logic: If Operator = Trainee → Then Enforce "Step-by-Step" confirmation (Click 'Next' 10 times). If Expert → Allow "Batch" confirmation (Click 'Done' once).

The "RightRead Info,and RightUnderstood" Time" LogicGate

Operators often ignore updates because they look like the old instructions. You must force acknowledgment of change.

• Mechanism: Track the Last_Acknowledged_Rev for every User-Product pair.
• Logic:
  • If UnitCurrent_Rev scans> at Station 10User_Last_Ack_Rev → Display WI-10 (Assembly).
  • IfThen UnitLock scans at Station 20 → Display WI-20 (Inspection).
  • If Unit is a "Variant B" model → Highlight unique steps (e.g., "Add extra gasket") in Red.

  Visual Standard

  • Format: HTML5 / Interactive. Avoid static PDFs where possible.Screen.
  • Media:Action: UseDisplay short,"Change loopedSummary" GIFs(Diff). forRequire complexDigital motions.Signature Ato 5-second video is worth 1,000 words of text.proceed.
  • Ergonomics: Text size must be readable from 1 meter away (Touchscreen distance).

  Revision Control & Instant Supersession

  The greatest risk in manufacturing is building today's product with yesterday's specifications. The digital link guarantees that the floor executes the current released engineering intent.

  The Push Mechanism

  When Engineering releases Rev B:

  1. Immediate Kill: Rev Ais marked "Obsolete" in the database.
  2. Active Wipe: Any screen currently displaying Rev A forces a refresh.
  3. Active Lock:Result: The system pauses the line and displays aexcuse "NewI Revisiondidn't Alert."know Theit operator must acknowledge the change before resuming.

  Pro-Tip: Use "Effectivity Dates" or "Serial Number Cut-ins." If a change applies only after SN 1000, the system must keep showing Rev A for SN 999, even if Rev Bchanged" is released.technically This manages WIP transition automatically.impossible.

Electronic Records & Sign-Offs (e-Records)

AnThe EWI is the Input; the e-Record is the legalOutput. equivalentEvery ofaction taken by the operator must generate a wet-inkpermanent, signature.immutable Itdatabase transformsrow. aThis "click"is intoyour adefense bindingduring statementan of fact.

Compliance Standardaudit (FDA 21 CFR Part 11 Style)/ GMP).

Data Capture Types

1. Implicit Data (Passive):
   • Who: User ID.
   • When: Timestamp (UTC).
   • Duration: Time_End - Time_Start. (Detects if an operator blindly clicked "OK" in 1 second for a 5-minute task).
2. Explicit Data (Active):
   • Confirmation: "I have inspected the seal." (Checkbox).
   • Variable: "Torque Value = 4.5 Nm." (Keypad/Tool Input).
   • Evidence: "Photo of the cable routing." (Camera Input).

Validation Logic

Even ifDo not regulatedaccept bydata blindly. Validate at the FDA,point adoptof these principles for robust liability protection.entry.

• Attribution:Range Check: If Input < 4.0 or > 5.0 → Then Reject Entry. Display "Out of Spec".
• Format Check: If Input is Text but Field expects Float → Then Block Entry.
• Mandatory Fields: If Critical Field is Empty → Then Disable "Complete" button.

The record"ALCOA+" Standard

Adhere to the ALCOA+ framework for data integrity. The MES architecture must linkguarantee undeniablythese five attributes for every record.

1. Attributable: Linked to a unique User ID.
2. Intent:Legible: Stored in human-readable format (or easily rendered).
3. Contemporaneous: Recorded at the exact moment of execution.
4. Original: The first record is the master.
5. Accurate: Validated against limits (Min/Max) at the source.

Handling Corrections

Operators make mistakes. The system must displayallow whatcorrection iswithout beingdestroying signed (e.g., "I certify this unit passed Visual Inspection").

Authentication: Critical actions require "Double Auth" (Password or Biometric re-entry).

Sign-Off Levels

• Level 1 (Passive): Scanned badge to log in. Tracks "Who was at the station."
• Level 2 (Active): Button press "Job Complete." Tracks "Who did the work."
• Level 3 (Certified): Password re-entry for critical decisions (e.g., Releasing a quarantined lot).

The Audit Trail

history.

The Audit Trail is the "Black Box" of the factory. It answers the "Who, What, When, Why" for every data point.Logic

Immutability Rule

• IfScenario: aOperator recordenters is"50mm", createdsaves, →realizes it should be "5.0mm".
• Action: Operator updates value.
• Database Record:
  • Row 1: Value="50", Status="Obsolete", Timestamp=10:00, User=John.
  • Row 2: Value="5.0", Status="Active", Timestamp=10:01, User=John, Reason="Entry Error".
• Constraint: It can never be deleted.
• IfNever perform an SQL UPDATE or DELETE on a recordproduction isrecord. wrongAlways (e.g., Operator entered 500 instead of 50) → CreateINSERT a new "Correction Record". The original 500 remains visible in history, crossed out but legible.

Traceability Query Logic

You must be able to reconstruct the history of a unit instantly.

• Query: "Show me all actions on Unit SN-12345."version.
• Result:
  1. 10:00 AM - Created (System)
  2. 10:05 AM - Assy Start (User: J.Doe)
  3. 10:15 AM - Torque Recorded: 5.0Nm (Tool: TQ-01)
  4. 10:20 AM - Inspection Fail (User: Supervisor)
  5. 10:30 AM - Rework Complete (User: RepairTech)

Final Checklist

Category	Metric / Control	Threshold / Rule
DeliveryAccess	ContextSkill Gate	WIBlock auto-loadsLogin basedif onUser_Certification Stationis +missing Productor IDexpired.
RevisionIdentity	LatencyAttribution	New100% Revisionsof liverecords instantlylinked to a specific User ID (<No 1generic min)logins).
Versioning	SafetyRev Match	"Obsolete"EWI docsRevision legallymust inaccessiblematch tothe OperatorsWork Order BOM Revision.
Sign-OffTraining	AuthenticationChange Control	CriticalForce Ops"Read require& Re-AuthenticationSign" (Pwd/Bio)pop-up when Operator encounters a new Revision.
Integrity	Immutability	Zero DELETE permissions on Production History tables.
Inputs	Logic Gates	Block "Next Step" until all Mandatory Fields are populated.
Audit	Retention	Logs kept for Product Lifetime + X Years
Integrity	Correction	NoField Deletes.edits Onlyrequire a "StrikethroughReason +Code" Newand Entry"
Visuals	Clarity	Keypreserve variancesthe highlightedold for mixed-model linesvalue.