FLD-HCSP is a miniature leak detection probe that is fully encapsulated. This high-performance sensing probe is designed for detecting leaks of refined products or crude oil in challenging small space locations where regular sensing probes may not be suitable. This probe can also be used as a cost-effective zero-false-alarms hydrocarbon fumes detector. Encased in a corrosion resistant stainless steel slotted cylinder, it is specially engineered for reliable operation in tank interstitial space, machine shafts, pumps, etc. The length of the probe is 3.74" (95 mm), with a diameter of 0.59" (15 mm). This sensing probe can be wired to the acquisition module through an optional jumper cable with a maximum length of 300 ft (90 m).
Advanced measurement techniques and PHMSA compliant leak detection algorithms are used by Naftosense acquisition modules to provide quick detection in a very wide temperature range. The sensing probe is cleanable and reusable with optional connectors for quick disconnection for cleaning.
FLD-HCSP probe is designed to be used exclusively with acquisition modules or intrinsically safe field boxes offered by Naftosense providing industry-standard analog outputs, dry contacts or serial communication protocols for flexible integration with third-party monitoring panels or PLC.
FLD-HCSP is a passive simple element and is safe for installations in hazardous locations when connected to intrinsically safe field box or wired through an approved Zener barrier to acquisition modules, alarm panels or other monitoring equipment installed in the safe area. Please contact Naftosense for additional information.
Agency Approvals
- In the US: Simple element, Intrinsically safe - Class I, Division 1, Groups A, B, C and D, Class I, Zone 0, AEx ia IIC
- Atex: Simple element, intrinsically safe – II 1 G, Ex ia IIC Gb T4
- IECEx: Simple element, intrinsically safe – Ex ia IIC Gb T4
Features
FLD-HCSP Hydrocarbon Leak Detection Probe Features and Benefits
Ultra‑Compact and Versatile
Designed to fit into tank interstitial spaces, pump seals, machine shafts, and other confined or hard-to-access areas.
Rapid, Reliable Zero-False-Alarms
Detects gasoline or diesel in under 1 minute; heavier hydrocarbons within 3–10 minutes depending on viscosity—ensuring swift response to prevent environmental damage and costly downtime
Reusable & Easy to Clean
Withstands contamination, and thanks to Naftosense’s polymer‑absorption design, it can be cleaned and redeployed—backed by a 10‑year warranty
Compatible & Intrinsically Safe
Works seamlessly with Naftosense acquisition modules or intrinsically safe field boxes. It can be wired up to 300 ft for flexibility and meets Class I, Div 1 / Zone 0 (T4) ratings
Built to Last
Survives temperatures from -40°F to 185°F and has an expected service life of over 30 years under real-world aging conditions
Smart Design Features
Low-profile and impact-resistant – Easy to mount away from foot traffic or moving equipment
Removable stainless steel slotted casing – Allows access to the sensor wire for testing and cleaning while keeping the mounting in place
Cleanable and reusable – Designed for repeated use and backed by a 10-year warranty (20-year service life)
Seamless integration – Compatible with all current Naftosense control systems
Two base models – Indoor and outdoor versions available
Sensitivity options – Choose high or low sensitivity depending on baseline contamination levels
Flexible wiring – Available with bare wire or connector-end options based on site needs
Specifications
FLD-HCSP Hydrocarbon Leak Detection Probe Specifications
Operating Life: 30+ years at 104°F (40°C), materials tested in natural ageing conditions
Compatibility: Approved Naftosense field boxes, monitoring modules and controllers
Dimensions: Length: 3.74" (95 mm); Diameter: 0.59" (15 mm)
Ingress Rating: IP68 - suitable for outdoor/direct burial
Operating Temperature Range: -40°F to 185°F (-40°C to 85°C)
Maximum Length of Lead Cable: 300 ft (90 m)
Hazardous Locations Classification: IS/ I/ 1/ ABCD/ T4 ; I/ 0/ AEx/ ia IIC T4 ; Class I, Zone 0, Ex ia T4 Class I, Div. 1, Groups A,B,C,D; T4 II 1 G Ex ia IIC T4 Ga
Warranty: 10 years
Typical Detection Times
Gasoline, Jet Fuel, Diesel: 20 to 28 seconds
Light Crude Oil: 45 to 60 seconds
Heavy Crude Oil, Dilbit: 3 to 4 minutes
Motor Oil, Silicone Oil: 8 to 10 minutes
Propane, Butane: 25 to 30 seconds
Applications
Practical Applications for the FLD-HCSP Miniature Leak Detection Probe
The FLD-HCSP is the ideal hydrocarbon leak detection solution for tight spaces and targeted applications across both commercial and industrial sectors. Its compact size, rugged design, and selective sensing capabilities make it an easy choice for engineers and system designers alike.
Commercial Applications: Gensets and Building Infrastructure
In many commercial buildings—both existing and under construction—fuel oil systems and generators use double-wall supply and return lines with a trap at the low point. These locations are perfect for installing the FLD-HCSP:
- Monitors for leaks at the plumbing run low points
- Reduces both installation and long-term maintenance costs
- Immune to water—only triggers on oil or fuel
- Ideal alternative to common float-type sensors, especially for generator packagers seeking cost-effective, low-maintenance solutions
Industrial Applications: Oil & Gas, Process, and Skid-Based Systems
The FLD-HCSP is also a powerful tool for leak monitoring in heavy-duty and oil & gas environments:
- Lift pumps – Detect seal failures and hydrocarbon leakage
- Tight double-wall containment – Works in small-diameter piping or tank walls
- Skid systems – Mounts at low-point drains on:
- Pump skids
- Filtration skids
- Lube skids
- LACT and metering systems
- Conditioning skids
- Loading/unloading modules
Most skids include a 1"–1.5" drain port—an ideal location for placing a single probe that can monitor the entire skid without clogging the flow path.
Q & A
FLD-HCSP Hydrocarbon Leak Detection Probe Q & A
Downloads
Naftosense FLD-HCSP Miniature Hydrocarbon Leak Detection Probe Datasheet
Talk to one of our technical specialists today at (855) 737-4718, or fill out our online form to learn more.