Mod 10 - Off-Spec Response

Module from the Laboratory Analyst Training Curriculum curriculum.

Module 10 — Off-Spec Response Procedures · Learning Objectives · 1. Execute immediate response when a product test exceeds spec. · 2. Communicate with operations, blending, and scheduling per defined escalation. · 3. Investigate root cause using method QC data, instrument records, and sample chain. · 4. Apply corrective blending, segregation, or reprocessing actions. · 5. Document and close out off-spec events with regulatory compliance in mind. · Off-Spec Response Workflow

Step	Action	Responsibility
1	Confirm result: verify calibration, rerun duplicate	Analyst
2	Check QC: instrument check std within limits	Analyst / Supervisor
3	Notify operations / blending / scheduling	Lab Supervisor
4	Place product on hold — no ship / no further blending	Operations
5	Pull retention sample, reanalyze by second method if available	Analyst
6	Determine disposition (reblend, reprocess, downgrade)	Planner / Ops
7	Document event in MOC/incident system	Lab Supervisor
8	Root cause and corrective action	Process Engineer / Lab
Common Off-Spec Causes
Property	Typical Cause	Fast Action
Gasoline RVP high	Butane overblend	Stop butane; reblend with low-RVP naphtha
ULSD sulfur high	HDS reactor WABT / catalyst issue	Reduce feed / increase H2; segregate
Jet flash low	Naphtha contamination in kero	Stop kero-to-jet; investigate mis-route
Diesel cloud high	Heavy cut / winter blending miss	Increase kerosene blend
FCC feed metals	Upstream crude switch	Check desalter, reduce severity
Lube VI low	Base oil slop / blending	Recheck base oil lot, reblend
Reformer RON low	Catalyst coking / severity	Increase WABT; plan regen
Retention Samples
Product	Retention	Notes
Finished gasoline	90 days minimum	EPA attestation
ULSD	90 days	EPA 40 CFR 80.584
Jet fuel	3 months (min)	Airline contract
Batch of crude cargo	Until bill settled	Dispute protection
Lube batch	1 year	Claims window
Investigation Checklist
Item	Check
Instrument calibration	Verify last cal and check-std drift
Reagent lot	Same lot across runs? Recent change?
Sampler	Correct location, purge adequate
Sample container	Correct container, seal intact
Chain of custody	Continuous, signed
Method software	Any recent update or parameter change
Process conditions	Unit rate, temp, rate change 24 h prior
Crude slate / feed	Recent crude switch or blend change
Regulatory Notes
Item	Requirement
EPA Tier 3 Gasoline	Per-gallon cap 80 ppm S, 10 ppm avg
RFS RINs	Off-spec renewable fuels may lose RIN generation
ULSD	>15 ppm S cannot be sold as ULSD
MARPOL / IMO 2020	Fuel <0.5% S for marine global; 0.1% ECA
Batch attestation	PTD per EPA 40 CFR 80.591
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Source: Laboratory_Analyst_Training_Curriculum_v1.xlsx · Sheet: Mod 10 - Off-Spec Response

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