Certificate of Conformance for Aviation Consumables: What Should Come With Your Order
Oct 8th 2026
A shipment of sealant arrives on a Friday afternoon for a check that starts Monday. Receiving inspection opens the box, finds no certificate of conformance, and quarantines the whole lot. The material is fine. The paperwork is not, and until that gets resolved the sealant may as well not exist.
Documentation issues account for a large share of rejected consumable shipments, and almost none of them involve a defective product. This guide covers what a certificate of conformance actually is, what has to be on it, how it differs from the other documents that show up in the box, and what should accompany dated chemistry when it arrives.
What a Certificate of Conformance Is
A certificate of conformance, often abbreviated CoC or C of C, is a signed declaration from a supplier stating that the material shipped meets the requirements of the purchase order and the specification it was ordered against.
It is a statement of compliance, not a test report and not an airworthiness approval. In government contracting the concept is formalized in FAR 52.246-15, which allows a supplier to certify conformance in lieu of source inspection. Commercial aviation borrowed the same logic.
The practical function is traceability. The CoC is what connects the drum in your stores to a specification, a batch, and a responsible manufacturer. Without it, the material has no documented identity.
Who Issues the CoC: Manufacturer vs. Distributor
This distinction causes more receiving disputes than any other, and it is worth being precise about.
Manufacturer CoC
The manufacturer certifies that the batch was produced and tested to the specification. This document originates at the point of production and references the manufacturer's own batch or lot number.
Distributor CoC
A distributor CoC certifies that the material supplied is the same material received from the manufacturer, unaltered, with traceability maintained through the distributor's quality system. It does not replace the manufacturer certification. It accompanies it.
Quality systems built around AS9120B, the aerospace standard for distributors, exist largely to make that chain defensible: receiving, storage, segregation, and record retention all feed the ability to certify what was shipped and where it came from. Our overview of compliance and trust across the aviation supply chain covers how that chain holds together across borders.
When your procedure requires manufacturer certification specifically, say so on the purchase order. A distributor cannot retroactively produce a document that was never requested at time of order.
What a Usable CoC Must Contain
Requirements vary by quality system, but a CoC that will survive receiving inspection generally needs all of the following.
- Purchase order number, so the document can be matched to the order
- Product identification: manufacturer name, part or product number, and description
- The specification and revision the material conforms to, such as MIL-PRF-81733 Type II Class B-2
- Batch or lot number, matching the number on the container label
- Quantity shipped
- Date of manufacture, and expiration or shelf life date for dated material
- A conformance statement and an authorized signature or approved electronic equivalent
The single most common defect is a mismatch between the batch number on the certificate and the number on the container. If those two do not agree, the document does not cover the material in front of you, and receiving is right to reject it. Specification revisions matter here too, since a certificate citing a superseded revision may not satisfy the maintenance data. Our MIL-SPEC overview explains how those designations are structured.
CoC vs. CoA vs. Certificate of Compliance
These three get used interchangeably in conversation and mean different things on paper.
| Document | What it states | When you need it |
|---|---|---|
| Certificate of Conformance (CoC) |
The material meets the purchase order and specification requirements | Standard requirement for most aviation consumables |
| Certificate of Analysis (CoA) |
The actual measured test results for that specific batch, with values | When your procedure or the specification requires batch test data, common for fuel tank sealants and inspection materials |
| Certificate of Compliance |
Generally used as a synonym for CoC, though some quality systems use it for regulatory compliance such as REACH or RoHS | Check your own procedure for which term it defines |
If you need numbers rather than a declaration, ask for the CoA explicitly. A CoC will not contain test values, and requesting one after delivery often means waiting on the manufacturer.
Why Aviation Consumables Rarely Receive an FAA Form 8130-3
Buyers new to consumable procurement sometimes request an FAA Form 8130-3 for sealant or primer. In almost all cases, that request cannot be filled, and the reason is worth understanding.
Form 8130-3 is an airworthiness approval tag for parts and articles, issued by an FAA-authorized source. Raw materials, chemicals, and standard hardware typically fall outside its scope. Their traceability is established through manufacturer certification and specification conformance instead.
So the correct documentation package for a quart of aerospace sealant or a case of aviation lubricant is a CoC citing the specification and batch, not an airworthiness tag.
What Should Arrive With Dated Chemistry
Two-part chemistry carries an extra documentation burden because the material has a finite life and that life started before you ordered it.
Date of manufacture, not date of shipment
Shelf life runs from manufacture. A container that shipped last week may have been produced eight months ago. The CoC should state the manufacture date so remaining life can be calculated at receipt, which matters most for sealants, two-part adhesives, and catalyzed epoxy primers. The same applies across the wider aviation chemicals range wherever a product carries a dated life.
Minimum remaining life on delivery
Many receiving procedures set a floor for how much shelf life must remain when material arrives, often expressed as a percentage of total life or a fixed number of months. If your procedure has one, put it on the purchase order. Suppliers cannot honor a requirement they were never given.
Batch segregation
Where a single order spans multiple batches, the paperwork should identify which quantity came from which batch. Consolidating that into one line makes the traceability unusable the moment a batch comes into question.
Storage conditions during transit are worth confirming for temperature-sensitive material as well, particularly premixed frozen cartridges that depend on an unbroken cold chain.
SDS and TDS: Which Document Answers Which Question
Neither of these is a conformance document, and neither belongs in a discussion of traceability. They answer different questions.
| Document | Answers | Typical use |
|---|---|---|
| Safety Data Sheet (SDS) |
Is this material hazardous, how do we handle, store, and dispose of it, and what happens in an exposure | Hazard communication, facility safety, shipping classification, waste handling |
| Technical Data Sheet (TDS) |
How does this material perform, how is it mixed and applied, what is the cure schedule and shelf life | Technical decisions: substitution, application planning, storage conditions |
| Certificate of Conformance (CoC) |
Is this specific batch what we ordered | Receiving inspection and traceability records |
The SDS is a product-level document that applies to every batch, so it does not need to arrive with each shipment. It does need to be current and accessible to everyone handling the material, which matters most for solvents and other flammables. For a fuller treatment, see our guide to safety data sheets and workplace compliance.
The TDS is where shelf life, storage temperature, mixing ratio, application life, and cure schedule live. It governs when a technical question comes up, and it is the document to check before assuming two similar coatings are interchangeable.
Common Reasons Receiving Inspection Rejects a Shipment
Most rejections trace back to a handful of avoidable causes. FAA guidance on building a receiving inspection system is set out in AC 20-154, and the recurring failure points are consistent across operations.
- Batch or lot number on the certificate does not match the container label
- Certificate cites a superseded specification revision, or omits the revision entirely
- Manufacture date missing, so remaining shelf life cannot be established
- Insufficient shelf life remaining against the receiving procedure's minimum
- Purchase order number absent, leaving the document unmatched to the order
- Distributor certification supplied where manufacturer certification was required
- Container label damaged or illegible, breaking the link to the paperwork
Nearly all of these are cheaper to prevent at the point of order than to resolve after delivery, when the aircraft is already in the hangar.
Set Documentation Requirements Before You Order
The most effective habit in consumable procurement is stating documentation requirements on the purchase order rather than assuming them. Specify whether you need manufacturer or distributor certification, whether a CoA is required, the minimum remaining shelf life, and any batch segregation requirement.
SkyGeek has supplied the aviation industry for more than 50 years and operates an AS9120B certified quality system, with specification data on the product page and conformance documentation available on request. There are no membership fees or minimum order quantities, so a single quart carries the same documentation as a pallet.
Browse aviation hangar supplies and consumables or contact the SkyGeek team to confirm documentation requirements before you place an order. Getting the paperwork right at the purchase order stage is what keeps the material moving through receiving and onto the aircraft.
Certificate of Conformance FAQ
What is a certificate of conformance?
A certificate of conformance is a signed supplier declaration stating that the material shipped meets the requirements of the purchase order and the specification it was ordered against. It establishes traceability by linking the material to a specification, a batch number, and a responsible manufacturer. It is not a test report and not an airworthiness approval.
What is the difference between a CoC and a CoA?
A certificate of conformance declares that the material meets requirements. A certificate of analysis provides the actual measured test results for that specific batch, with values. If your procedure requires batch test data rather than a declaration, request the CoA explicitly at time of order.
Do aviation consumables need an FAA Form 8130-3?
In almost all cases, no. Form 8130-3 is an airworthiness approval tag for parts and articles issued by an FAA-authorized source. Raw materials, chemicals, and standard hardware typically fall outside its scope, and their traceability is established through manufacturer certification and specification conformance instead.
Should a certificate of conformance show the date of manufacture?
For any material with a shelf life, yes. Shelf life runs from date of manufacture rather than date of shipment or receipt, so without that date you cannot calculate remaining life at receiving. Specify it as a requirement on the purchase order for sealants, adhesives, primers, and inspection materials.
Is a distributor certificate of conformance acceptable?
It depends on your quality procedure. A distributor CoC certifies that the material supplied is the unaltered material received from the manufacturer with traceability maintained. Some procedures accept it, others require manufacturer certification as well. Where manufacturer certification is required, state that on the purchase order.
Does an SDS need to arrive with every shipment?
No. A safety data sheet is a product-level document that applies across batches rather than a shipment-specific one. It does need to be current and accessible to everyone handling the material, and it should be obtained whenever a formulation changes or the sheet is revised.
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