whirrwork

Autonomous floor scrubber

Nilfisk Liberty SC50

Walk-behind-sized autonomous scrubber-dryer with CopyCat (teach a route), Fill-in and manual modes; disc or REV orbital head.

Made by Nilfisk · Official page · Spec sheet

Gross weight is published only with a 75 kg operator on board (479.5–484.4 kg), so it is not listed as the machine weight. Public buyer record: Houston Airport System bought five Liberty SC50s with a 3-year service plan for USD 258,740 in total (City Council item S21-E29785, 2021-03-30, https://houston.novusagenda.com/agendapublic/CoverSheet.aspx?ItemID=22377&MeetingID=477, checked 2026-10-28).

Whirrwork assessment, not a lab test

Not enough evidence to rate

  • Only 1 independent source found; at least 2 are needed.
  • No independent field trial or test of how well it does the job (certifications cover safety or airspace rules, not performance).

1 independent source found · spec transparency 6 of 8 key specs published. How we rate.

Specs (maker-published)

SpecValueAs published · source
Runtime / flight time360 min“It provides up to 6 hours of runtime and 55,000 square feet of coverage on a single charge” nilfisk.com
checked Oct 28, 2026
Cleaning width510 mm“Scrub Path 20 in (51 cm) (Nilfisk Liberty SC50 fact sheet L4002N_0420, US-CA; copy hosted by a dealer)” info.warehousedirect.com
checked Oct 28, 2026
Tank57 L“Solution Tank 15 gal (57 L); Recovery Tank 14 gal (53 L) (Nilfisk fact sheet)” info.warehousedirect.com
checked Oct 28, 2026
Top speed1.055 m/s“Max Speed Autonomous 2.35 mph (1.055 m/s) (Nilfisk fact sheet)” info.warehousedirect.com
checked Oct 28, 2026
Coverage rate maker claim1,895 m²/h“Max Theoretical Productivity in Autonomous 20,400 ft2/hr (1895 m2/hr) (Nilfisk fact sheet)” info.warehousedirect.com
checked Oct 28, 2026
Noise63 dBA“Sound Pressure Level (IEC 60335-2-72) 63 dB A (Nilfisk fact sheet)” info.warehousedirect.com
checked Oct 28, 2026

Not published by the maker (or not found yet): Weight, Sensors.

What the maker claims

  • maker claim Consistently delivers between 98% and 99.5% coverage; third-party certified to robotic safety standards (fact sheet: CSA/ANSI C22.2 No. 336-17) (nilfisk.com)

Claims are not independently checked unless an evidence item below says so.

Independent evidence

  1. Independently documented deployment Supports the job fit

    E29785 - Autonomous Scrubber Dryers - MOTION (City Council agenda item 5, S21-E29785)
    City of Houston City Council, 2021-03-30

    Houston Airport System bought five Liberty SC50s (USD 258,740 incl. a 3-year service plan) to run nightly at George Bush Intercontinental and Hobby airports on over 500,000 sq ft of terrazzo.

    A public purchase record: it shows the planned use, not measured results.

Jobs it can do

From its robot type. Whether it suits your site depends on the specs above and on the job's checklist.

Compare with other autonomous floor scrubbers