Which AS-B format for a compact LoRaWAN sensor or gateway?

Compact sensor (0.1-0.5 L): AS-B/XS (5 cm²). Mid-size IoT device (0.5-2 L): AS-B/S (10 cm²). Outdoor LoRaWAN/NB-IoT gateway (2-10 L): AS-B/M or AS-B/L. Embedded module on robot or drone: by volume + reinforced adhesive version if severe vibration.

My battery is Li-SOCl2 — can AS-B interact chemically with the cell?

No. The SRD material is a chemically inert mesoporous aluminum oxide. No electrochemical interaction with Li-SOCl2, Li-Po, Li-Ion, or NiMH batteries. No risk of accelerated self-discharge, cell swelling, or separator degradation.

Is it UL-listed? Compatible with IoT certifications (LoRaWAN Alliance, GCF, PTCRB)?

REACH compliant. RoHS compatible composition. UL: not yet Recognized. LoRaWAN Alliance, GCF, PTCRB: these certifications cover device radio and functional compliance, not anti-condensation accessories. No incompatibility. NEMA 4X / NEMA 6 housings: compatible — same physical principle as IP66.

AS-B sticker integrated into a Xenilabs IoT outdoor sensor

Electronics & IoT Application

Anti-Humidity Protection for IoT Outdoor Enclosures IP65+

Q: My LoRaWAN outdoor sensors see their batteries drain before scheduled lifetime. Can condensation really be the cause?

Yes, and it's an often-underestimated factor. Internal humidity creates parasitic leakage currents between PCB traces. On a Li-SOCl2 19 Ah LoRaWAN battery, these leakages can divide real-world autonomy by 2 to 4× without any active-mode current measurement showing anomalies. The AS-B sticker eliminates this source by keeping internal humidity below 60%.

Q: My onboard T/RH sensor returns aberrant values after deployment. How does AS-B help?

A T/RH sensor placed inside a housing where internal humidity exceeds 90% RH measures the housing's internal state more than the external environment. The AS-B sticker keeps internal humidity below 60%, the nominal operating range of virtually all T/RH sensors on the market.

Q: Does the sticker affect LoRaWAN, NB-IoT, or Sigfox radio range on my device?

No, on the contrary. The SRD material is passive and does not absorb radio frequencies. By eliminating condensation on RF components, the sticker prevents the antenna mismatch drift seen on humid enclosures, preserving nominal radio range over time.

Q: Is it compatible with conformal coating on my PCB?

Yes. The AS-B sticker coexists without interaction with a conformally coated PCB. SRD is H2O-selective and indifferent to organic solvents. AS-B and conformal coating are complementary: coating for components, AS-B for internal air.

Q: How do I integrate AS-B in my IoT assembly line?

Manual or automated placement, less than 10 seconds per enclosure. Standard ambient assembly conditions (RH < 80%, room temperature). Storage in original packaging, no dry room required.

Q: MOQ and lead time for an IoT manufacturer?

Standard MOQ: 5,000 units for XS format, 2,500 units for S, M, L. Standard lead time: 6 to 8 weeks after order confirmation. Express on request. Tiered pricing.

Q: What about my sensors deployed for 2-3 years whose batteries are starting to fail? Can I retrofit?

Technically yes — the AS-B sticker can be applied during a maintenance operation. But condensation accumulated over previous years may have already damaged certain components. Retrofit AS-B prevents further degradation but does not repair the past.

Your IoT device is designed to last 7 years on a single battery. Internal condensation cuts that to 18 months — silently, sensor by sensor, across your entire deployed fleet.

The AS-B sticker installs inside sensor housings, LoRaWAN gateways, NB-IoT devices, and embedded modules. It adsorbs water vapor as soon as internal humidity exceeds 60% RH, then regenerates spontaneously when air dries. Zero energy, zero maintenance, lifetime aligned with your equipment.

8× usable capacity vs silica gel 0 W consumption — battery autonomy intact LoRaWAN, NB-IoT, LTE-M, Sigfox, Wi-SUN REACH — Made in France

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Why IoT outdoor enclosures suffer from humidity

The day/night thermal cycle inside an IP65/IP66 housing

An outdoor IoT enclosure rated IP65 or IP66 is sealed against liquid water and dust — but not against water vapor. That technical nuance changes everything for equipment expected to operate 5 to 10 years in the field.

During the day, the housing heats up under sun exposure. Internal pressure rises, and air escapes through micro-leaks at gaskets, cable glands, or pressure equalization vents if fitted. At nightfall, temperature drops. Internal pressure drops with it, and outdoor air loaded with water vapor flows back through the same micro-leaks.

Over a few cycles, internal humidity climbs steadily. Once dew point is reached, condensation forms — and IoT outdoor housings are particularly vulnerable: low internal thermal output, high cold-wall surface area relative to internal volume.

Why IoT outdoor amplifies the problem

An IoT enclosure isn't a camera or an industrial automation cabinet. Three characteristics make condensation proportionally more costly on an IoT fleet:

Long autonomous lifecycle

The enclosure is engineered to last 5 to 10 years without human intervention. Over that span, the factory-installed silica gel pack saturates in 6 months and captures nothing for the remaining 9.5 years.

Dense deployment in inaccessible locations

Sensors deployed in fields, forests, underground parking lots, on streetlight poles, in storm drains, on industrial rooftops. A field service intervention often costs more than the value of the sensor itself.

Zero tolerance on autonomy

A mains-powered enclosure can compensate humidity drift with a heating system. A LoRaWAN sensor on Li-SOCl₂ cannot — every additional milliwatt consumed is a month of autonomy lost.

Three cumulative damages

What designers underestimate

Accelerated battery drain

Internal humidity creates parasitic leakage currents between PCB traces — at levels invisible in active-mode current measurement but cumulative over years. On a typical Li-SOCl₂ 19 Ah battery in a LoRaWAN sensor, these leakages can divide real-world autonomy by 2 to 4×.

On a 10,000-sensor fleet, this means double the battery replacements over 10 years — a hidden cost that appears in no initial spec sheet.

Onboard sensor drift (T°, RH, air quality)

A T°/RH sensor placed inside a housing where internal humidity exceeds 90% RH measures the housing's internal state more than the external environment.

Result: aberrant data sent to the cloud, false alerts, no possibility of remote recalibration, loss of operator confidence. For an air quality sensor, an ambient temperature sensor, a soil moisture probe — the very business value of the measurement collapses.

The AS-B sticker keeps internal humidity below 60% RH — the nominal operating range of virtually all T°/RH sensors on the market.

Antenna mismatch and radio range loss

Liquid water — or even simply condensed vapor on RF components — alters local dielectric properties. Result: progressive antenna mismatch on the integrated antenna and reduced LoRaWAN, NB-IoT, or Sigfox range.

A sensor designed to communicate at 3 km in a semi-rural area can drop to 800 m after a few seasons. The device "works" — it transmits — but with multiplied retry duty cycle and therefore degraded battery autonomy.

Operational cost

The real cost on a deployed IoT fleet

For an IoT operator (smart agriculture, smart city, asset tracking, predictive maintenance), real condensation cost is measured in TCO over 10 years.

~40%

of environmental sensor failures

linked to internal condensation (Bosch / IFM / TE diagnostics)

200-1,200 USD

per field service intervention

excluding sensor value (PTC Field Service, SightCall)

2× to 4×

battery replacement frequency

driven by leakage currents from internal humidity

On a fleet of 10,000 LoRaWAN sensors deployed over 5 years:

With saturated silica gel: cumulative failure drift reaches 5 to 15% depending on environment (urban / agricultural / coastal)
Avoidable service cost: 100,000 to 1,500,000 USD over deployment period
Excluding SLA disputes and contractual penalties if availability commitments are in place

This is the economy the AS-B sticker protects — for a unit investment of 1 to 5 USD per sensor depending on format.

State of the art

Why current solutions don't work

Factory-installed silica gel packs

Saturated in 3 to 6 months on an exposed outdoor enclosure
Never replaced once the sensor is deployed (intervention cost exceeds sensor value)
Designed for transport, not for 5 to 10 years of autonomous operation

→ Exactly the pain point AS-B solves: spontaneous regeneration, unlimited lifetime.

Pressure equalization vents (Gore PolyVent)

Does not control internal humidity: water vapor passes through the membrane
Climate chamber tests: an IP66 housing with breather alone condenses as much as a bare housing
Significant initial cost (5-15 USD) plus assembly labor + extra hole = long-term infiltration risk

→ AS-B and pressure vents are complementary: vent for pressure, AS-B for humidity.

Conformal coating on PCB

Protects the PCB, not the integrated sensor which must remain in contact with internal air
Onboard antenna remains exposed — radio mismatch still occurs
Battery remains exposed — secondary leakage paths uncovered

→ AS-B and coating are complementary: coating for components, AS-B for internal air.

Hygrostat + heating resistor

Consumes 10 to 400 W continuously — incompatible with battery or solar power
Kills autonomy in weeks instead of years
Electromechanical component = additional point of failure

→ Applicable to mains-powered gateways, incompatible with battery-powered IoT sensors. AS-B is the only viable passive alternative for the battery-powered segment.

Combo silica gel + breather

Combines the first two solutions. Stacks both individual limitations: pack saturated in months, breather powerless against humidity, plus extra hole in the enclosure.

See the full comparison of 5 solutions →

AS-B Solution

Passive protection for IoT outdoor enclosures

Self-adhesive patch built around a patented mesoporous SRD material, developed at Université Claude Bernard Lyon 1 and IFP Energies Nouvelles, licensed through Pulsalys.

How to integrate it in a sensor, gateway, or IoT device

Compact sensor

LoRaWAN, NB-IoT, Sigfox, Wi-SUN

Volume 0.1-0.5 L (3-17 fl oz). AS-B/XS. Apply opposite the exposed T°/RH sensor.

Mid-size IoT device

Asset tracker, level sensor, beacon

Volume 0.5-2 L (17-68 fl oz). AS-B/S. Away from RF components.

LoRaWAN/NB-IoT gateway

Outdoor

Volume 2-10 L (68-338 fl oz). AS-B/M or L. Combine with Gore breather if fitted.

Embedded module

Robot, drone, autonomous vehicle

Volume 0.3-3 L. Severe vibration: reinforced adhesive version (IEC 60068-2-6).

IoT technical compatibility

Operating temperature range	−20 °C to +70 °C (−4 °F to +158 °F)
Radio compatibility (sub-GHz, 2.4 GHz)	Yes — LoRaWAN, NB-IoT, LTE-M, Sigfox, Wi-SUN, BLE, Wi-Fi
Conformal-coated PCB compatibility	Yes — SRD H₂O-selective, indifferent to organic solvents
Onboard T°/RH sensor	Yes — AS-B keeps RH < 60% and preserves accuracy
Li-SOCl₂, Li-Po, Li-Ion, NiMH batteries	Yes — no electrochemical interaction
PPE on assembly line	None — inert mineral material
REACH / RoHS	Compliant / compatible
NEMA 4X / NEMA 6 housings	Compatible — same physical principle as IP66
Installation time	< 10 seconds per enclosure, no tools

How it works over time

RH > 60%: water vapor adsorption by capillary condensation in the mesopores
RH < 60%: release of adsorbed water → the material returns to its initial state

Usable capacity over the at-risk range (60-90% RH) is 8 times higher than standard silica gel. Over the typical lifetime of an outdoor IoT sensor (5 to 10 years), the sticker stays active without any intervention.

Lab test & B2B IoT validations

IP66 climate chamber validation

30 °C → 0 °C (86 °F → 32 °F) ramp over 1 h 20. Three identical IP66 housings:

Configuration	Result
Bare housing (control)	Visible condensation
Housing + pressure vent only (Gore Vent)	Visible condensation (matches control)
Housing + AS-B sticker	Zero internal condensation

Read the full test report →

Active IoT B2B validation programs

Weather instrumentation

Leading Nordic manufacturer, outdoor T°/RH instruments deployed worldwide

Connected water quality / pool sensors

French specialist, pool-side measurement, battery longevity at stake

Outdoor agricultural robots

European manufacturer, embedded electronics in open-field exposure

Industrial sensors / automation

German optical sensor manufacturer for automation

FAQ

IoT outdoor enclosures and anti-condensation

My LoRaWAN sensors see their batteries drain before scheduled lifetime. Can condensation really be the cause?

Yes, and it's an often-underestimated factor. Internal humidity creates parasitic leakage currents between PCB traces. On a Li-SOCl₂ 19 Ah LoRaWAN battery, these leakages can divide real-world autonomy by 2 to 4× without any active-mode current measurement showing anomalies. The AS-B sticker eliminates this source by keeping internal humidity below 60%.

My onboard T°/RH sensor returns aberrant values after deployment. How does AS-B help?

A T°/RH sensor placed inside a housing where internal humidity exceeds 90% RH measures the housing's internal state more than the external environment. The AS-B sticker keeps internal humidity below 60% — the nominal operating range of virtually all T°/RH sensors. The sensor regains its accuracy and the drift disappears.

Does the sticker affect LoRaWAN, NB-IoT, or Sigfox radio range?

No — on the contrary. The SRD material is passive and does not absorb radio frequencies. By eliminating condensation on RF components, the sticker prevents the antenna mismatch drift seen on humid enclosures — preserving nominal radio range over time.

Is it compatible with conformal coating on my PCB?

Yes. The AS-B sticker coexists without interaction with a conformally coated PCB. SRD is H₂O-selective and indifferent to organic solvents. AS-B and coating are complementary: coating for components, AS-B for internal air.

Which AS-B format for a compact LoRaWAN sensor or a gateway?

Compact sensor (0.1-0.5 L / 3-17 fl oz): AS-B/XS (5 cm²)
Mid-size IoT device (0.5-2 L / 17-68 fl oz): AS-B/S (10 cm²)
Outdoor LoRaWAN/NB-IoT gateway (2-10 L / 68-338 fl oz): AS-B/M or AS-B/L
Embedded module: by volume + reinforced adhesive if severe vibration

My battery is Li-SOCl₂ — can AS-B interact chemically with the cell?

No. The SRD material is a chemically inert mesoporous aluminum oxide. No electrochemical interaction with Li-SOCl₂, Li-Po, Li-Ion, or NiMH batteries. No risk of accelerated self-discharge, cell swelling, or separator degradation.

How do I integrate AS-B in my IoT assembly line?

Manual or automated placement, < 10 seconds per enclosure. Standard ambient assembly conditions (RH < 80%, room temperature). Storage in original packaging, no dry room required.

MOQ and lead time for an IoT manufacturer?

Standard MOQ: 5,000 units for XS format, 2,500 units for S, M, L. Standard lead time: 6 to 8 weeks after order confirmation. Express on request. Tiered pricing — details on quote page.

What about my sensors deployed for 2-3 years whose batteries fail? Can I retrofit?