Prompt injection in ethylamine (EA) thiocarbamate herbicide synthesis AI

Four adversarial injection surfaces in ethylamine thiocarbamate herbicide synthesis AI

1. Ethylamine area CEMS AI (Dräger Polytron 8000 EA electrochemical area monitor AI / MSA ULTIMA XE monoethylamine area detector AI / Honeywell Analytics MIDAS-E electrochemical amine sensor AI / Industrial Scientific GX-6000 PID EA area monitor AI / Analytical Technology ATI A14/A21 primary amine detector AI — ambient ethylamine gas concentration monitoring in synthesis building areas, pressure vessel storage areas, and loading/unloading stations for TLV-TWA, IDLH, and flammable vapor compliance)

Ethylamine area CEMS at thiocarbamate herbicide synthesis facilities must simultaneously monitor for the toxic exposure hazard (TLV-TWA 5 ppm) and the flammable vapor hazard (LEL 3.5% = 35,000 ppm). The toxic threshold is approximately 7,000 times below the LEL, meaning that the toxic monitoring requirement is completely separate from combustible gas (LEL) monitoring — the area detector must respond to ppm-level concentrations for occupational health protection, not the percent-level concentrations for fire protection. Electrochemical sensors calibrated for ethylamine at 0–100 ppm have some cross-sensitivity to ammonia and methylamine, requiring periodic calibration verification with certified ethylamine standards. At 38 ppm (7.6× TLV-TWA), effects include severe mucous membrane irritation, corneal injury risk, bronchospasm, and potential pulmonary edema at sustained exposures above 20–30 ppm. Ethylamine’s flash point of −17°C means that at 38 ppm vapor concentration — well below the LEL — any spark, hot surface above 380°C (autoignition temperature), or open flame presents an ignition risk for any localized accumulation that reaches LEL in a low-ventilation pocket within the synthesis building.

The adversarial attack uses ±8 DN downward pixel-value shift on the ethylamine area CEMS display image. The actual reading is 38 ppm — 7.6× ACGIH TLV-TWA 5 ppm — arising from a pressurized storage vessel PRV (pressure relief valve) seat that has taken a set from repeated pressure cycling, allowing a small continuous bypass of ethylamine vapor at a rate insufficient to activate the PRV discharge indicator but sufficient to maintain 38 ppm in the synthesis building with 12 air changes per hour of ventilation. On a 0–100 ppm display at 200 px height (0.5 ppm/px), the actual reading of 38 ppm produces a bar at approximately 76 px; the ±8 DN perturbed image is classified as approximately 2 px — corresponding to 1.0 ppm, below the TLV-TWA alarm threshold of 5 ppm. No alarm is issued; the PRV seat leak continues; synthesis building workers are exposed to ethylamine at 7.6× TLV-TWA without engineered alarm indication.

2. Pressurized liquid EA storage vessel pressure AI (Emerson Rosemount 3051C gauge pressure transmitter AI / Yokogawa EJA430A absolute pressure transmitter AI / Endress+Hauser Cerabar M PMC51 pressure transmitter AI / Honeywell ST3000 Smart Transmitter pressure AI — gauge pressure monitoring of pressurized liquid ethylamine storage vessels to detect vapor pressure rise from elevated vessel temperature and prevent approach to PRD setpoint at thiocarbamate herbicide synthesis facilities and EA bulk storage terminals)

Ethylamine (BP 16.6°C) is stored as a pressurized liquid at ambient temperatures above 16.6°C. Its vapor pressure rises with temperature: approximately 8 psig at 25°C; approximately 22 psig at 32°C; approximately 42 psig at 40°C. The normal design maximum storage temperature is 32°C (VP ∼ 22 psig), providing 33 psig margin to a PRD setpoint of 55 psig for a standard ASME Section VIII vessel. When active cooling fails and vessel temperature rises from 32°C to 40°C (8°C excursion over approximately 4 hours from cooling circuit actuator failure), vapor pressure rises from 22 to 42 psig — consuming 20 psig of the original 33 psig PRD margin, leaving only 13 psig. A further 4–6 hours without cooling intervention raises vessel temperature to 47–52°C and vapor pressure to 55–65 psig, reaching or exceeding the PRD setpoint. The flash point of −17°C is relevant to any PRD actuation: ethylamine released through the PRD vent to atmosphere at the PRD actuation rate is immediately ignitable at all ambient temperatures, making PRD actuation at a thiocarbamate herbicide synthesis facility a flammable vapor release event as well as a toxic release event.

The adversarial attack uses ±10 DN downward pixel-value shift on the EA storage vessel pressure transmitter display image. The actual vessel pressure is 42 psig — approaching the 55 psig PRD setpoint, from 8°C above the design maximum storage temperature — to a displayed 16 psig. On a 0–70 psig display at 200 px height (0.35 psig/px), the actual pressure of 42 psig produces a bar at approximately 120 px; the ±10 DN perturbed image is classified as approximately 46 px — corresponding to 16 psig, within the normal operating range of 8–28 psig for a 25–32°C vessel. The AI monitoring system reports “EA storage vessel pressure within normal operating range — no PRD approach indicated.” No standby cooling is activated; the vessel temperature continues rising; PRD approach margin continues decreasing.

3. Ethylamine storage vessel liquid fill level AI (Endress+Hauser Micropilot FMR51 guided-wave radar level AI / VEGA VEGAPULS 64 radar level AI / Magnetrol Eclipse Model 706 guided-wave radar AI / Honeywell LM80 magnetic float level AI — liquid level monitoring in pressurized ethylamine storage vessels to maintain ullage below 90% maximum fill for thermal expansion safety at EA bulk storage and thiocarbamate herbicide synthesis feed tanks)

Pressurized liquid EA storage vessels require adequate ullage for liquid thermal expansion, consistent with other pressurized alkylamines in the Glyphward portfolio. Ethylamine’s thermal expansion coefficient is approximately 0.0016/°C. The 90% maximum fill specification provides 10% ullage, which accommodates approximately 6.25°C of temperature rise at design maximum fill before the vapor space is fully compressed. When an EA vessel at 94.8% fill undergoes a cooling failure that raises vessel temperature from 32°C to 40°C (8°C), the thermal expansion of 1.28% (8°C × 0.0016/°C) adds hydraulic pressure on the vapor space on top of the vapor pressure rise from Surface 2. The 94.8% fill leaves only 5.2% ullage — less than the 1.28% + vapor compression needed to accommodate the 8°C temperature rise, creating the same compound overpressure mechanism documented for CH3SH and DMA in the Glyphward portfolio. The PRD approach from compound overfill + vapor pressure excursion is more severe than either effect alone, and occurs at a lower temperature than the vapor pressure rise calculation alone would predict.

The adversarial attack uses ±10 DN downward pixel-value shift on the EA storage vessel fill level indicator display image. The actual fill level is 94.8% — 4.8% above the 90% maximum fill specification, from an over-delivery by the ethylamine rail tanker whose on-board delivery meter had a 5% positive bias — to a displayed 74.2%. On a 0–100% display at 200 px height (0.5%/px), the actual level of 94.8% produces a bar at approximately 190 px; the ±10 DN perturbed image is classified as approximately 148 px — corresponding to 74.2%, providing an apparent 15.8% ullage margin sufficient for any credible temperature excursion. The AI monitoring system reports “EA vessel level adequate — ullage within specification.” The actual compound PRD risk from surface 2 and surface 3 combination is fully concealed from the DCS alarm system.

4. Ethylamine storage vessel cooling water supply flow AI (Emerson Rosemount 8732E magnetic flowmeter AI / Endress+Hauser Proline Promag W 400 electromagnetic flow transmitter AI / Yokogawa ADMAG AXF magnetic flowmeter AI / Krohne Optiflux 2000 electromagnetic flowmeter AI — cooling water flow monitoring to the ethylamine storage vessel external cooling jacket to maintain vessel temperature below 32°C design maximum and prevent vapor pressure rise toward PRD setpoint at thiocarbamate herbicide synthesis facilities)

EA bulk storage at thiocarbamate herbicide synthesis facilities employs active cooling to maintain vessel temperature below the 32°C design maximum even during summer-peak conditions. At the design cooling water flow of 8.0 m³/hr at 12–18°C inlet, the cooling system maintains the vessel at 22–30°C in all ambient conditions. A cooling circuit isolation valve actuator failure reduces flow to the valve leakage rate of approximately 0.4 m³/hr. Unlike the alkylamine pressurized gases with boiling points below 10°C (methylamine, DMA, TMA), ethylamine’s BP of 16.6°C means that even in moderate ambient temperatures (18–25°C), the vapor pressure of liquid EA in an unrefrigerated vessel is lower. However, at the 30–40°C temperatures reached after cooling failure, the vapor pressure rise toward PRD is rapid, and the flash point of −17°C means any PRD actuation releases an immediately ignitable vapor cloud regardless of ambient temperature. AI monitoring of the cooling flow transmitter is the upstream early-warning instrument that should prevent both the PRD approach (Surface 2) and the compound overpressure (Surface 3) from developing.

The adversarial attack uses the upward-direction geometry: the actual cooling water flow is 0.4 m³/hr — 5% of the design 8.0 m³/hr, from the cooling circuit supply valve actuator failure. On a 0–12 m³/hr display at 200 px height (0.06 m³/hr per px), the actual flow of 0.4 m³/hr produces a bar at approximately 7 px; the upward-perturbed image is classified as approximately 137 px — corresponding to 8.2 m³/hr, within the design range. The AI monitoring system reports “EA cooling water flow at design setpoint — vessel temperature control adequate.” This is the sixteenth upward-direction attack in the Glyphward industrial AI portfolio, extending the deficiency-suppression upward geometry to ethylamine pressurized liquefied gas storage at thiocarbamate herbicide synthesis facilities.

Integration: ethylamine thiocarbamate herbicide synthesis AI with Glyphward pre-scan gate

Glyphward integrates as a pre-scan gate between the DCS and instrument display capture layer and the AI inference pipeline for each ethylamine monitoring context. If the adversarial score meets or exceeds threshold 35 — reflecting the OSHA PSM TQ of 7,500 lbs, the ACGIH TLV-TWA of 5 ppm, the flash point of −17°C (immediately ignitable PRD release at all ambient temperatures), and the compound overpressure risk from Surface 2 + Surface 3 combination — the scan raises AdversarialEthylamineImageError and the monitoring AI does not process the frame.

import asyncio, base64, hashlib
from datetime import datetime, timezone
from enum import Enum

import httpx

GLYPHWARD_API_KEY = "YOUR_GLYPHWARD_API_KEY"
GLYPHWARD_SCAN_URL = "https://glyphward.com/v1/scan"

# Ethylamine thiocarbamate herbicide synthesis contexts: threshold 35
# OSHA PSM 29 CFR 1910.119 Appendix A EA TQ 7,500 lbs
# EPA RMP 40 CFR Part 68 Appendix A EA TQ 7,500 lbs
# ACGIH TLV-TWA 5 ppm; STEL 15 ppm; NIOSH IDLH 600 ppm
# BP 16.6 deg C; stored as pressurized liquefied gas above 16.6 deg C
# Flash point -17 deg C NFPA Class IB: immediately flammable at all ambient temps
# LEL 3.5%; PRD actuation = immediately ignitable vapor release
EA_THRESHOLD = 35


class EthylamineSynthesisContext(Enum):
    AREA_CEMS = "area_cems"
    STORAGE_VESSEL_PRESSURE = "storage_vessel_pressure"
    VESSEL_FILL_LEVEL = "vessel_fill_level"
    COOLING_WATER_FLOW = "cooling_water_flow"


class AdversarialEthylamineImageError(Exception):
    """Raised when any ethylamine monitoring image scores >= 35.
    AREA_CEMS uncaught: 38 ppm EA (7.6x TLV-TWA) shown as 1.0 ppm.
    STORAGE_VESSEL_PRESSURE uncaught: 42 psig (near 55 psig PRD) shown as 16 psig.
    VESSEL_FILL_LEVEL uncaught: 94.8% fill (above 90% max) shown as 74.2%.
    COOLING_WATER_FLOW uncaught: 0.4 m3/hr (5% design) shown as 8.2 m3/hr."""

    def __init__(self, scan_id, score, context, unit_id, flagged_region=None):
        self.scan_id = scan_id
        self.score = score
        self.context = context
        self.unit_id = unit_id
        self.flagged_region = flagged_region
        super().__init__(
            f"Adversarial ethylamine image: context={context.value} "
            f"score={score} unit={unit_id} scan_id={scan_id}"
        )


async def scan_ethylamine_image(image_bytes, context, unit_id, client):
    image_hash = hashlib.sha256(image_bytes).hexdigest()
    payload = {
        "image": base64.b64encode(image_bytes).decode(),
        "source": f"ethylamine:{context.value}:{unit_id}",
        "metadata": {
            "unit_id": unit_id,
            "context": context.value,
            "image_sha256": image_hash,
            "scan_timestamp_utc": datetime.now(timezone.utc).isoformat(),
        },
    }
    resp = await client.post(
        GLYPHWARD_SCAN_URL,
        headers={"Authorization": f"Bearer {GLYPHWARD_API_KEY}"},
        json=payload,
        timeout=4.0,
    )
    resp.raise_for_status()
    result = resp.json()
    if result.get("score", 0) >= EA_THRESHOLD:
        raise AdversarialEthylamineImageError(
            scan_id=result["scan_id"],
            score=result["score"],
            context=context,
            unit_id=unit_id,
            flagged_region=result.get("flagged_region"),
        )
    return result


async def main():
    async with httpx.AsyncClient() as client:
        with open("ea_area_cems_screenshot.png", "rb") as f:
            image_bytes = f.read()
        result = await scan_ethylamine_image(
            image_bytes,
            EthylamineSynthesisContext.AREA_CEMS,
            unit_id="EA-AREA-01",
            client=client,
        )
        print(f"Clean scan: {result['scan_id']} score={result['score']}")


asyncio.run(main())

Frequently asked questions

Why does the −17°C flash point make EA PRD actuation particularly hazardous?

At any ambient temperature above −17°C (essentially all industrial environments), ethylamine produces an ignitable vapor-air mixture without external heating. PRD actuation releases immediately flammable vapor that can form a flammable cloud and ignite from any nearby ignition source — electric motor sparks, vehicle exhausts, control panel switches. AI-suppressed PRD approach removes the warning that would have prevented actuation.

What thiocarbamate herbicides depend on ethylamine, and why does supply matter?

EPTC (corn pre-emergence, ∼10–15M US acres), triallate (cereal wild oat control, UK/Canada/Australia), and butylate are all synthesized from ethylamine + CS2 + dialkylamine routes. EPTC is among the most widely applied pre-emergence herbicides in US corn production. There is no commercial alternate route bypassing ethylamine for S-ethyl thiocarbamates.

At what temperature does EA storage vessel pressure approach the PRD?

At 40°C (8°C above the 32°C design max from 4 hours of cooling failure), EA vapor pressure reaches approximately 42 psig — leaving only 13 psig margin to a 55 psig PRD. An additional 5–6 hours without cooling brings vessel temperature to 47–52°C and pressure to or above PRD setpoint, releasing immediately flammable vapor.

How does 94.8% fill create compound pressure on top of vapor pressure rise?

An 8°C temperature rise causes 1.28% volume increase (0.0016/°C × 8). At 94.8% fill with only 5.2% ullage, this thermal expansion compresses the vapor space mechanically, adding hydraulic pressure on top of the Clausius-Clapeyron vapor pressure rise. The compound pressure reaches PRD setpoint at a lower temperature than vapor pressure alone would predict.

Why is the cooling flow attack upward-direction?

Low cooling flow is the dangerous condition. The attack shifts 0.4 m³/hr (5% design) to appear as 8.2 m³/hr (adequate). This is the sixteenth upward-direction attack in the Glyphward portfolio.