Environmental Sampling Tubing: LDPE vs. HDPE vs. FEP-Lined vs. Silicone

Use HDPE for PFAS sampling, LDPE for general groundwater sampling, FEP-lined LDPE for VOC sampling (not PFAS), and silicone only inside a peristaltic pump head. Match the inner diameter to your pump, use bonded dual tubing for bladder and double-valve pumps, and always confirm the requirements in your site sampling plan or state guidance before you buy.

Why tubing choice matters

Tubing is not just a conduit. Depending on its material, it can absorb contaminants, leach plasticizers or react with the compounds you are trying to detect. For trace-level analytes such as PFAS and VOCs, the tubing the sample runs through matters as much as the pump and the bottles.

Sampling tubing compared

Material	Best for	Watch-outs	Sizes and price at EE+S
LDPE	Routine groundwater sampling; economical and flexible	Standard LDPE is not recommended for PFAS sampling; can stretch under its own weight in deeper wells; not for barbed fittings	ID 0.17–0.5 in; 100, 250 or 500 ft; 15–215
HDPE	PFAS sampling, deeper wells and chemically demanding sites	Stiffer, so harder to handle in shallow wells or tight bends	ID 0.5 or 0.81 in; 100, 200 or 500 ft; 56–280; PFAS, PFOS and PFOA free
FEP-lined LDPE	VOC sampling: the inert FEP liner protects the sample while the LDPE jacket stays flexible	FEP is a fluoropolymer, so it is not recommended for PFAS sampling; costs more; not for barbed fittings	ID 0.17, 0.25 or 0.375 in; 100, 250 or 500 ft; 145–1,275
Silicone	Pump head tubing for peristaltic pumps	Gas-permeable, so not suitable as the sample line, especially for VOCs	ID 0.1875, 0.25 or 0.375 in; 2–4
Bonded dual tubing	Bladder and double-valve pumps that need an air line and a sample line	Pick LDPE or FEP-lined LDPE to match your analytes	LDPE: 205–510; FEP-lined: 230–1,145

Prices are current ranges on envisupply.com and vary by size and length. Always check local, state and federal requirements for your site.

Choose tubing by application

• General groundwater sampling (non-PFAS, non-VOC): LDPE is a cost-effective, widely accepted choice.
• PFAS sampling: use HDPE. Avoid standard LDPE, FEP and PTFE.
• VOC sampling: LDPE with an FEP liner limits interaction between the sample and the tubing wall.
• Peristaltic pumps: silicone belongs in the pump head; run the sample through LDPE or HDPE.
• Chemically aggressive matrices: HDPE offers the best chemical resistance among the common polyethylene options.
• Two-line pumps: bonded dual tubing keeps the air and sample lines together, reduces tangling and simplifies deployment.

Match tubing size to your pump

Inner diameter affects flow rate and purge volume, so pick a size that matches your pump and application. Not every material is available in every size, and LDPE, FEP-lined LDPE and silicone are not recommended for barbed fittings. For pump selection, see our guide to pumps for 2-inch monitoring wells. If you collect filtered samples, add an in-line filter; see our in-line groundwater filter comparison.

Buying tubing and renting the pump

Tubing is a purchase, sold by the roll, and is commonly dedicated to a single well or replaced between wells to avoid cross-contamination, so check your sampling plan. The pump is where rentals make sense: see our rental pumps. FEP-lined tubing costs several times more than plain LDPE, so use it where your analytes call for it rather than as a default. For a decision guide organized by analyte and regulation, see Which Sample Tubing Should I Use?

Frequently asked questions

What tubing should I use for PFAS sampling?

HDPE is the industry-recommended tubing for PFAS programs. Avoid standard LDPE, which can absorb and later release PFAS-related compounds, and avoid FEP and PTFE, which are fluoropolymers. Our HDPE tubing is listed as PFAS, PFOS and PFOA free. Always verify against your site sampling plan.

What is the difference between LDPE and HDPE sampling tubing?

LDPE is cheaper and more flexible but can stretch in deep wells and is not recommended for PFAS. HDPE is stiffer, stretches less, gives better flow and lift in deeper monitoring wells, and has higher chemical resistance, but is harder to handle in tight spaces.

Can I use silicone tubing as the sample line?

No. Silicone is intended for the pump head of a peristaltic pump, where its softness and elasticity suit repeated compression. Its gas permeability lets volatile compounds pass through the tubing wall, so route the sample through LDPE or HDPE instead.

Find the right tubing for your next sampling event

Browse our sampling tubing and accessories and full sampling supplies, or contact us or call 717.901.8891 and we’ll help you match tubing to your pump and analytes.