Your line gets AI. Your assessor gets evidence.
From 20 Jan 2027, machinery sold in the EU must protect its safety software from corruption and record every intervention. Your fab, or your fab customer, already buys tools against SEMI E187. Kernwall OS is designed to hand over the evidence both ask for, inside the machine or beside it.
Why now
Two rulebooks close in on one box.
The EU law reaches you if you build the machine. The fab standards reach you if you supply the tool. An AI station inside your machine or line answers to both.
- 2023TSMC made SEMI E187 a tool purchase requirement.
- Dec 2025Taiwan launched E187 certification for equipment suppliers.
- 19 Nov 2026EN 50742, the standard for these clauses, publishes.
- 20 Jan 2027The Machinery Regulation makes cybersecurity a CE requirement.
Reference architecture
Where the box sits on your plant network.
On your site-operations network if your fab buys it, or inside the tool if you build the tool. Either way, bundles enter at one import station and nothing leaves.
The appliance's two placements on the Purdue levels, and the one path a bundle takes in.
- OutsideVendor
- Vendor build
Builds and signs release bundles. Holds no key to your site and no route into it.
Signed bundles on USB or a one-way diode
- Vendor build
- L4–5Enterprise
- Business IT
ERP, email, the office network. The appliance needs no route here, nor to the internet.
- Business IT
- L3.5IT/OT DMZ
- Import station
Verifies, re-scans and re-signs each bundle with the site key, then passes it down.
Site-signed bundles only
- Import station
- L3Site operations
- MES and historian
Recipes, lots, quality records and process data.
- OT edge platform
Moves plant data to apps. May carry its own IEC 62443-4-2 certificate.
- Placement A · fab-ownedAppliance
Serves models on the plant network over an OpenAI-compatible API. Egress denied.
- MES and historian
- L2Area supervision
- Tool and cell
HMI, tool host PC, inspection cameras.
- Placement B · shipped with a toolAppliance in a tool
The tool's Linux computer, shipped by the machine builder and updated through the same import station.
- Tool and cell
- L0–1Control and process
- Controllers and safety
PLCs, tool controllers, safety functions. The appliance advises people; it sends no commands here.
- Controllers and safety
Your OT edge platform moves plant data to the apps that use it. Some edge platforms now hold their own IEC 62443-4-2 product certificate: TTTech's Nerve platform since Dec 2025, Moxa's UC Series industrial computers at SL2 since Jul 2026. A GPU server beside yours for local models is a new host device in your zone, and it needs evidence of its own. Kernwall OS serves models over an OpenAI-compatible API, so tools from any vendor call it like any other service on your plant network.
What it runs here
Three jobs for your fab's first appliance.
Each job keeps its data where it was made. The window runs the first. Every row links to its session and its hardware tier.
- Placement B · shipped with a tool · Kernwall Edge
Visual inspection in the tool
A fanless box ships as the inspection computer in your tool or cell. Images stay in the cell, and flagged parts wait for your inspector's verdict.
- 40–130 W
- Factory line, vehicle, forward site
- Placement A · fab-owned · Kernwall Workgroup
Copilot over SOPs and work instructions
A server on your site-operations network answers your process engineers from documents they can already open, cited to procedure and section.
- 1.5–3 kW
- Comms room on a 230 V / 16 A circuit
- Placement A · fab-owned · Kernwall Edge
Voice at the line
Gloves on, your operators ask out loud. Speech recognition and the model run in a box at the line, so the audio stays on site.
- 40–130 W
- Factory line, vehicle, forward site
EU Machinery Regulation 2023/1230
Annex III, clause by clause.
These duties fall on whoever puts the machine on the market. If you build it, you can only show what its parts can prove. Kernwall OS is designed to prove its part.
- §1.1.9 · Connection
Connecting another device, directly or remotely, must not lead to a hazardous situation.
“…the connection to it of another device…”
No outbound path and no remote-access service in the image. Data and updates come in only as signed bundles through the import station.
Evidence you take awayEgress audit report; listening-services manifest per release (planned)
- §1.1.9 · Hardware
Protect the hardware that gives access to safety-critical software, and record interventions in it.
“…collect evidence of a legitimate or illegitimate intervention…”
Measured boot into the TPM: a swapped disk, board or firmware changes the measurements, and the disk key stays sealed to the known-good values.
Evidence you take awayMeasured-boot log and PCR values per boot, in the audit chain
- §1.1.9 · Software and data
Identify the software and data critical for compliance, and protect them from corruption.
“…shall be identified as such…”
Signed kernel image and a read-only dm-verity root. Models and configuration ship in the same signed bundles, so an altered byte fails verification.
Evidence you take awaySignature verification transcript; digests per release
- §1.1.9 · Identification
The machine identifies the software it needs to operate safely, at all times.
“…in an easily accessible form…”
The appliance reports its image version, its digest and the hash of every loaded model, offline, on demand.
Evidence you take awayIdentity record per appliance; SBOM and AI-BOM per release
- §1.1.9 · Modification
Record every intervention in the software, or change to it or its configuration.
“…a modification of the software installed…”
Hash-linked audit chain of updates, configuration changes, model loads and imports. Export is a copy, never a move.
Evidence you take awayExportable audit chain with its verification output
- §1.2.1 · Control systems
Control systems withstand foreseeable malicious attempts that could cause a hazard.
“…reasonably foreseeable malicious attempts from third parties…”
Published threat model; signed-only updates; A/B slots with automatic rollback if a new release fails its checks.
Evidence you take awayThreat model and rollback record; penetration-test report (planned)
- §1.2.1(f) · Tracing log
Keep a log of interventions and of safety-software versions uploaded, for five years after each upload.
“…the tracing log of the data generated in relation to an intervention…”
Every bundle version installed is a record in the audit chain, kept on the appliance and in each export.
Evidence you take awayInstall history per appliance, verifiable offline
Annex III §1.1.9 and §1.2.1 mapped to appliance controls and the evidence each one produces.
The draft standard for these clauses gives you two routes: Clauses 5 and 7 if your machine is not designed to IEC 62443, Clauses 6 and 8 if it is. A component built to IEC 62443-4-2 keeps the second route open. Until the Official Journal cites the standard, following it gives no presumption of conformity, so you may reach 20 Jan 2027 without one. That makes the evidence each supplier ships worth more.
SEMI E187 · E188 · E191 · IEC 62443-4-2
What your fab asks of a Linux box.
SEMI E187 sets the baseline for the computers in fab equipment. Whether it applies depends on who installs the box.
Your fab buys it for its own network
E187 covers the Windows or Linux computers of fab equipment, and E188 excludes factory-provided systems, so neither applies directly. Your security team may still hold any supplier-delivered Linux box to the same bar. We'll ask them which parts they apply.
- E187 as a bar
- 62443-4-2 component
You ship it inside or beside your tool
Then the appliance is your tool's Linux computer. E187 applies through the tool, E188 applies to you and your component suppliers, and E191 applies if it joins the factory network. The mapping below is written for you.
- E187
- E188
- E191
- 62443-4-2
- E187 · OS support
A vendor-supported OS with a patch and update procedure.
One vendor-supported image, versioned as a whole, with A/B updates, rollback and an emergency channel for actively exploited flaws.
Evidence you take awaySupport-end date per release; release ledger; CVE scan per image
- E187 · Network security
Encrypted protocols, a known set of services and ports, no plaintext services.
Default-deny egress. Telnet and FTP are not in the image. Every listening service is named in a manifest published with each release.
Evidence you take awayEgress audit report; listening-services manifest per release (planned)
- E187 · Endpoint protection
Malware scanning, restricted removable media and a vulnerability remediation process.
Read-only root, so nothing persists to infect. Every import is scanned and signature-checked at the import station; USB media is accepted only for signed bundles.
Evidence you take awayImport-station scan and verification log; published CVE scan; disclosure policy
- E187 · Security monitoring
Logins and configuration changes are logged.
Hash-linked audit chain of logins, configuration changes, model loads and imports.
Evidence you take awayExportable audit chain, offline
- E188 · Integration
Malware-free delivery, installation, upgrade, support and restoration, disk replacement included.
Sealed shipment with a measured first boot. Updates only as signed bundles. A replacement disk is re-provisioned from the signed image, never cloned.
Evidence you take awayBoot measurements at install; bundle signatures; re-provisioning record
- E191 · Status reporting
Report the device's identity and its OS manufacturer, name, version and build.
The appliance reports its image identity and digest. SECS-II reporting (E191.1) waits until a tool maker asks for it.
Evidence you take awayIdentity record per appliance
- 62443-4-2 · HDR 3.14 RE 1
Check the integrity and authenticity of firmware, software and configuration before boot.
UEFI Secure Boot → signed UKI → PCR 11 → dm-verity.
Evidence you take awayMeasured-boot log; PCR values per release
- 62443-4-2 · HDR 3.12 / 3.13
Provision the supplier's and the asset owner's roots of trust on the device.
Our signing keys at build; your site re-signs with its own keys at import, so the box can trust you over us.
Evidence you take awayKey ceremony record; trust-store listing
- 62443-4-2 · CR 3.4 RE 1, HDR 3.10 RE 1
Software and every update are authenticated before installation.
One signed bundle carries OS, driver, model and evidence; unsigned or altered bundles are refused.
Evidence you take awaySignature verification transcript
- 62443-4-2 · CR 3.9
Protect audit logs from unauthorised access, change and deletion.
Append-only hash chain; any edit breaks verification from that record on.
Evidence you take awayChain verification output
- 62443-4-2 · CR 7.8
Keep an inventory of the component's parts.
SBOM and AI-BOM for every image and every model.
Evidence you take awaySBOM and AI-BOM files
SEMI requirement areas and IEC 62443-4-2 SL2 host-device requirements mapped to appliance controls.
Is a read-only, signed-only root with scanning at import enough for E187's endpoint protection and IEC 62443's malicious-code requirement at SL2, or will your assessor expect an anti-malware agent on the box? We will settle it with our first design partners' assessors rather than promise either answer here. SL2 is the level ISASecure recommends as the minimum for off-the-shelf components; its certification sits on our certification roadmap.
Test it
Bring your purchase terms to a pilot.
Tell us which of these clauses appear in your supplier requirements, and who checks them. The pilot runs on your hardware, inside your wall, against that list.