Flame-retardant
PROTAPE® PVC 371 HT (LD)
Highly flexible PVC ventilation hose with spring steel wire embedded in the wall and fabric reinforcement. HT (High-Temperature) variant — wider temperature range than LD/MD/HD variants. M1 fire classification (higher than the M2 variants'). Service from −10 °C to +110 °C, short-term peak up to +120 °C. Designed for ventilation and extraction applications where flame retardance is required.
- Flame-retardant NF P 92-503 M1
- −10 to +110 °C
- Peak +120 °C
- Highly flexible
- Fabric-reinforced
- Cut to length
Why this hose?
PROTAPE® PVC 371 HT (LD) belongs to the PROTAPE® PVC 371 range — a broadly used family of flame-retardant ventilation hoses with spring steel wire in the wall. The high-temperature (HT) variant with M1 fire class, up to +110 °C continuous is what distinguishes this variant from the others in the range.
The spring steel wire embedded in the wall gives shape stability and bend resistance, combined with the PVC wall's flexibility and the fabric reinforcement's abrasion resistance. The result is a versatile ventilation hose that can both be bent and hold shape — important in installations where the hose must follow moving structures or complex pipe routings.
Where it is used
The hose typically sits in industrial ventilation and extraction systems, from smaller machine connections to central extraction systems. Flexibility and flame retardance are both essential parameters in most installations.
In HVAC installations it serves as connection between fixed pipework and equipment — where temperature can swing seasonally and fire authority requirements for materials must be respected.
In everyday talk we call it a "flame-retardant ventilation hose" — the go-to when air needs moving without the hose cover itself becoming the fire source.
Technical specifications
Technical specifications for PROTAPE® PVC 371 HT (LD).
| Material | PVC wall, fabric-reinforced, spring steel wire |
|---|---|
| Colour | Grey |
| Temperature | −10 to +110 °C |
| Temperature (peak) | +120 °C |
| Flame retardance | NF P 92-503 M1 |
| Conformity | NF P 92-503 M1, RoHS |
| Cut to length | Yes |
| Manufacturer SKU group | 3711015 |
Dimensions and ordering
Standard dimensions for PROTAPE® PVC 371 HT (LD).
| Inner Ø |
Outer Ø |
Wall thickness |
Working pressure |
Vacuum |
Bend radius |
Max. length |
Weight |
Article no. |
|---|---|---|---|---|---|---|---|---|
| 50.5 | 55.5 | 0.25 | 0.24 | 0.145 | 29 | 15 | 0.14 | 37100511015 |
| 75.6 | 80.6 | 0.25 | 0.16 | 0.08 | 41 | 15 | 0.18 | 37100761015 |
| 80 | 85 | 0.25 | 0.15 | 0.08 | 43 | 15 | 0.2 | 37100801015 |
| 90 | 95 | 0.25 | 0.135 | 0.07 | 48 | 15 | 0.22 | 37100901015 |
| 101.5 | 107 | 0.25 | 0.12 | 0.05 | 54 | 15 | 0.27 | 37101021015 |
| 126.5 | 132 | 0.25 | 0.095 | 0.035 | 67 | 15 | 0.34 | 37101271015 |
| 140 | 145.5 | 0.25 | 0.085 | 0.035 | 73 | 15 | 0.38 | 37101401015 |
| 151.5 | 157 | 0.25 | 0.08 | 0.035 | 79 | 15 | 0.41 | 37101521015 |
| 160 | 165.5 | 0.25 | 0.075 | 0.02 | 83 | 15 | 0.35 | 37101601015 |
| 180 | 186.5 | 0.25 | 0.065 | 0.02 | 93 | 15 | 0.4 | 37101801015 |
| 202.3 | 208.3 | 0.25 | 0.6 | 0.02 | 105 | 15 | 0.6 | 37102031015 |
| 254 | 260 | 0.25 | 0.045 | 0.015 | 131 | 15 | 0.78 | 37102541015 |
| 305 | 311 | 0.25 | 0.04 | 0.01 | 158 | 10 | 0.93 | 37103051015 |
Fields without a value (—) are not specified in the manufacturer's factsheet. Overpressure and underpressure values are recommended operating limits; the product can be subjected to higher loads on request. Bend radius is measured along the inside of the hose bend.
Standards and compliance
PROTAPE® PVC 371 HT (LD) conforms to:
- NF P 92-503 M1. Flame retardance standard.
- RoHS. Directive 2011/65/EU.
- REACH (EC 1907/2006). The manufacturer's REACH declaration is available for download.
Documentation and downloads
Additional documents about this hose, its compliance and installation. Click to download as PDF in a new tab.
Help with material selection
Although this hose isn't ATEX-relevant, these two articles provide useful background on electrical resistance and industrial safety — important if you later combine the hose with electrical equipment or work in mixed environments:
The invisible weakest link
Why a conductive or antistatic hose isn't sufficient on its own — and what grounding means for the complete system.
Know your ohm
The difference between antistatic and conductive, which resistance limits apply where, and how to measure them correctly.
Industries that use it
The PROTAPE® PVC 371 family is used across industries where air needs moving without the hose cover itself becoming the fire source:
In ordinary ventilation and extraction installations the hose combines flexibility with shape stability — important parameters when the hose must be routed around obstacles.
In HVAC and air conditioning systems it's used in smaller dimensions as flexible connectors. In industrial ventilation it's used in larger dimensions as the main system trunk.
Custom lengths and assemblies
The hose is delivered on 10 m and 20 m rolls. We cut to length and fit fittings, sleeves or couplings as a finished assembly.
For serial deliveries we can establish consistent assembly across the delivery.
Frequently asked questions
What's the difference between M1 and M2 in the NF P 92-503 scale?
M1 is the higher fire class — "non-flammable" or "very hard to ignite". M2 is "hard to ignite". The HT variant has M1, which is stricter than the LD/MD/HD variants' M2 — suitable for warmer applications where fire risk must be further minimised.
What's the difference between HT and MD/LD?
The HT variant is specifically designed for warmer service: continuous up to +110 °C (vs MD/LD's +80 °C) and peak up to +120 °C. Fire classification is also higher (M1 vs M2). Choose HT when the medium is continuously above +80 °C.
Does it tolerate welding fume from high-energy processes?
Yes. Welding fume from TIG or MIG welding can reach +100-110 °C at the hood inlet — that's covered by the HT variant continuously. For more extreme processes (plasma, laser, induction) the temperature should be cross-checked against the hose's limits.
Where is it typically used?
On extraction arms in workshops, welding facilities, chemical industries and heat ventilation where temperature is above +80 °C continuously. Also in vehicle and machine installations where a compact and heat-resistant hose is required.
Is it as flexible as the LD variant?
Not entirely. The HT wall is marginally stiffer because the material has additives that increase heat resistance. It's still 6:1 compressible, but handles slightly differently from the standard LD variant.
Is it ATEX-approved?
No. The PVC wall is insulating. For ATEX in combination with high temperatures, choose a metal hose (METAL HOSE INOX 376) or a conductive variant.