Extension Hoses 351A

GASTEC 351A Extension Sampling Hose

GASTEC 351A Extension Sampling Hoses

Deep Reach. Safe Remote. Confined Space Pre-Entry Sampling.

The GASTEC 351A Extension Hose series enables operators to draw accurate gas samples from deep confined spaces—such as sewer manholes, chemical storage tanks, ship cargo holds, and underground utility vaults—without ever entering the hazardous environment. By mounting the GASTEC detector tube directly at the tip of the hose, the gas is measured in real time at the actual depth, completely eliminating line absorption and dead-volume lag.

5 / 10 / 30mStandard Length Options Available
ConfinedSpace Pre-Entry Safe Sampling
ZeroDead-Volume Sample Distortion
WeightedBrass Tip with Depth Markers

Tube Mounted at the Sampling Tip

Detector tube is positioned at the remote intake end, eliminating hose wall gas adsorption errors.

Multiple Available Lengths

Available in standard 5-meter (351A-5), 10-meter (351A-10), and 30-meter (351A-30) reels.

Direct GV-100S Coupling

Equipped with a precision quick-connect adaptor that slots directly into the GV-100S pump inlet.

Weighted Brass Protective Head

Heavy nosepiece keeps the line hanging vertically in turbulent drafts and protects the glass tube.

Durable Fluoro-Elastomer Tubing

Non-kinking, oil-resistant, and chemically inert tubing withstands aggressive industrial fluids.

Convenient Storage Spool Reel

Comes wound on a rugged handheld spool reel with carrying handle for rapid deployment and retrieval.

Safe Remote Testing. Sample Dangerous Confined Spaces from Above.

01

Mount Tube in Probe Tip

Break both tips of the detector tube and secure it firmly inside the weighted brass tip holder with arrow pointing toward hose.

02

Lower to Target Depth

Unspool hose from reel and lower probe steadily into manhole or tank using the 1-meter increment depth markings.

03

Draw Sample & Retrieve

Connect the pump to the top end, pull the handle, wait for indicator to pop in, then reel up probe and read tube stain.

GASTEC 351A Extension Hose
04

In-Situ Reaction Principle

Because the tube reacts at the bottom, zero gas volume is diluted or lost along the length of the hose.

05

Airtight Quick Adaptor

Precision-machined connector creates a 100% airtight vacuum seal with the pump inlet sleeve.

06

High Tensile Cord Integration

Reinforced internal tensile member prevents stretching or accidental line snapping under heavy pull.

Municipal Sewer & Stormwater Vaults

Measures H₂S and explosive methane at water level before opening manhole covers and lowering workers.

Petrochemical Storage Tanks

Checks hydrocarbon vapors, benzene, and oxygen deficiency at the bottom, middle, and top of fuel tanks.

Marine Vessel Ballast & Cargo Tanks

Tests deep double-bottom tanks and holds from the weather deck through sounding pipes and ullage ports.

Grain Silos & Agricultural Pits

Samples toxic fumigant residues (phosphine, methyl bromide) and carbon dioxide in deep grain storage bins.

Underground Cable & Pipe Ducts

Ensures telecom and electric utility tunnels are free from toxic gas pockets before cable pulling.

Wastewater Digesters & Wet Wells

Profiles gas layering and toxic vapor stratification safely without breathing apparatus or harnesses.

The Specs Speak for Themselves

Technical advantages that ensure accurate remote gas readings with the 351A hose series.

Did you know?

Zero Gas Lag

placing the tube at the remote tip eliminates sample adsorption on the internal hose wall

Did you know?

Up to 30m

length configurations enable pre-entry atmospheric checks in the deepest industrial vessels

Did you know?

1m Markers

graduated depth markers printed along the hose provide exact vertical location verification

GASTEC 351A Extension Hose Technical Specifications

Available model lengths, materials, compatibility, and physical specifications.

Specification ParameterDetails
Product FamilyGASTEC 351A Series Extension Sampling Hoses
Available Models351A-5 (5 meters) / 351A-10 (10 meters) / 351A-30 (30 meters)
Compatible Sampling PumpsGASTEC GV-100S, GV-100LS, GV-110S
Tubing MaterialHigh-grade flexible fluoro-polymer / synthetic elastomer
Tip ConstructionHeavy-duty weighted brass with internal silicone tube holder
Depth MarkingsPrinted white depth increments every 1 meter
Storage SystemLightweight, high-strength plastic reel with winding crank handle
Operating Temperature-10°C to +50°C

Frequently Asked Questions

Mounting the tube at the remote end ensures the gas reacts immediately upon entering the probe. If the tube were at the pump, reactive gases (like H₂S or NH₃) would stick to the inside of a long hose, causing severe under-reading.
No! Because the detector tube is located at the remote intake tip, the volume of air passing through the tube is determined strictly by the pump stroke volume (100 mL), regardless of hose length.
Yes. The hose is constructed with non-sparking brass hardware and anti-static materials, making it safe for use in ATEX explosive atmosphere inspections.
Insert an unopened glass tube into the tip, connect the pump at the reel end, and pull a full stroke. If the pump handle returns completely after 1 minute, the entire hose line and seal are airtight.
It is strongly recommended to use a single factory 30-meter hose (351A-30) rather than splicing shorter hoses, as extra connectors create potential vacuum leak points.