For most laboratories, the right pump depends on the task: a diaphragm pump for chemistry, filtration and rotary evaporation (oil-free, ~1–20 mbar); a two-stage rotary vane or scroll pump for freeze-drying and general vacuum (~10-3 to 10-2 mbar); and a turbomolecular pump backed by a scroll pump for high-vacuum analytical instruments. Match the pump to the application, not the other way round.
Match the pump to the task
| Lab application | Recommended pump | Typical vacuum |
|---|---|---|
| Filtration, degassing | Diaphragm | Rough (~100–5 mbar) |
| Rotary evaporation | Diaphragm + controller | ~1–100 mbar |
| Freeze-drying | Two-stage rotary vane or scroll | Medium (~10-2–10-3 mbar) |
| Vacuum ovens, gel drying | Two-stage rotary vane or scroll | Medium |
| Analytical instruments (MS, SEM) | Turbomolecular + backing pump | High/UHV |
Oil-free or oil-sealed in the lab?
Most modern labs prefer oil-free pumps (diaphragm, scroll) for cleanliness and low maintenance. Oil-sealed rotary vane pumps are still used where you need a deeper vacuum at low cost — freeze-drying, or as a backing pump. See our comparison of scroll vs rotary vane.
Chemical resistance
If you pump solvents, acids or other aggressive vapours, choose a chemical-duty pump with resistant wetted materials (PTFE diaphragms) and a vapour-handling design. The wrong materials corrode fast.
Noise and bench space
Labs are shared spaces, so quiet running and a small footprint matter. Diaphragm and scroll pumps are generally quiet and bench-friendly.
Sizing
Match pumping speed to your chamber or rotary-evaporator size and the vapour load. Girovac services and sources spares for KNF and VacuuBrand diaphragm pumps and supplies rotary vane and scroll pumps for the lab.
Specifying a lab pump?
Tell us the application, solvents and target vacuum and we’ll recommend the right pump – new or reconditioned. Email [email protected] or request a quote.
Frequently asked questions
What vacuum pump should I use in a laboratory?
It depends on the task: a diaphragm pump for chemistry, filtration and rotary evaporation; a two-stage rotary vane or scroll pump for freeze-drying and general vacuum; and a turbomolecular pump on a backing pump for high-vacuum instruments.
Which laboratory vacuum pumps are oil-free?
Diaphragm and dry scroll pumps are oil-free, making them the usual choice for clean lab work. Turbomolecular pumps are also oil-free but need an oil-free backing pump to stay contamination-free.
What vacuum pump is best for a rotary evaporator?
A chemical-resistant, oil-free diaphragm pump with an integrated vacuum controller, so you can match the vacuum to each solvent. See our guide to vacuum pumps for freeze-drying and rotary evaporation.
Written by the Girovac technical team. Girovac Ltd has supplied and serviced industrial and laboratory vacuum equipment from its North Walsham workshop since 1983. Last updated: July 2026.