A 2940 nm Er:YAG laser removes roughly 20 to 50 microns of tissue per pass.
That single number explains most of the confusion in this product category.
Vendors put Er:YAG next to CO2 in the same brochure and quote similar prices. They are not similar machines. CO2 at 10,600 nm ablates 300 to 1,500 microns in one session. Er:YAG at 2,940 nm works in thin layers, which is why a full treatment takes two to four sessions instead of one.
Neither is better. They solve different problems. And the price gap between them is smaller than the clinical gap.
Three numbers that decide whether it fits your clinic
20 to 50 microns per pass. Here is the physics in plain words. Water in skin loves 2,940nm and ignores 10,600nm. Energy lands shallow and does most of its work before it reaches anything you would call heat damage. Side effects drop with it. Darker skin types tolerate it better. Recovery gets shorter. Then comes the part we would rather not print. A shallow pass cannot reach a deep scar in one appointment.
3 to 7 days of downtime. Published ranges put Er:YAG recovery at 3–7 days, against 5–10 for CO2 and 1–3 days of redness for thulium. If your clients are lunch-break customers, this number matters more than anything on the spec sheet.
300 to 900 per session. That is the range quoted across clinic pricing surveys. CO2 runs 500–1,500, thulium 250–700. Your local market has to support the fee, and your room has to turn over fast enough to hit it.
Er:YAG vs CO2 vs thulium
| Er:YAG 2940 | CO2 10,600 | Thulium 1927 | |
| Depth per pass | 20–50 µm | 300–1,500 µm | 200–300 µm |
| Сеансы | 2–4 | 1–3 | 3–5 |
| Downtime | 3–7 days | 5–10 days | 1–3 days redness |
| Best for | Fine lines, sensitive areas | Deep wrinkles, severe scarring | Pores, mild to moderate scarring |
| PIH risk, type III–VI | Moderate | Moderate to high | Low to moderate |
| Machine cost, reference | $10k–25k | $15k–35k | $8k–20k |
Treat the machine costs as an order-of-magnitude reference. Quotes for the same nominal spec can vary by a factor of three. The variance usually sits in the tube, the scanner and the warranty — not the wavelength.
What the clinical evidence actually shows
The most useful head-to-head is Lu et al. 2022 in Lasers in Medical Science. Twenty seven Asian patients, split-face , thulium 1927 nm against Er :YAG 2940 nm, treating atrophic acne scars.
Global assessment improvement came out at 36.54% for thulium and 35.27% for Er:YAG. No statistically significant difference.
The differences showed up in recovery, not results. Pain scores 2.74 versus 3.47. Crust resolution 3–5 days versus 5–7 days.
Read that before paying a premium for a wavelength. Same result on Asian-skin acne scars. Gentler recovery on the thulium side. So where does Er:YAG actually pay off? Superficial texture. Small zones, eyes and mouth, where a 20 to 50 micron pass does the job without committing the whole depth in one go.
Four things a quotation will not tell you
Tube type. RF metal tubes are rated 20,000–50,000 hours. DC glass tubes realistically run 1,500–3,000. At 12–25 treatments a month, that is a new tube every 6 to 12 months. The purchase price gap between the two configurations is small. The five-year cost gap is not.
Scanner head. Adjustable 3/5/7mm spots cover most work. On large areas the scanner matters more than the spot size. Ask for the scan patterns, and for the maximum coverage per pass.
Cooling and pain protocol. Er:YAG gets described as less painful than CO2. It still needs air or contact cooling, and most clinics put topical anaesthetic on for 30–45 minutes. Skip integrated cooling and you buy longer chair time and fewer bookings per day.
Spares and service. Handpieces, fibres and the articulated arm are the parts that fail. Get the price list and the lead time to your country in writing. A 12,000 machine with a six-week handpiece wait costs more than a 15,000 machine with local stock.
Three acceptance tests before you sign
Continuous output drift under 10% across a 10-minute run
Burn paper test with fewer than 5% missing spots over the scanned area
A 48 to 72 hour burn-in test before shipping, with the report attached
Ask for the report, not the promise.
When Er:YAG is the wrong purchase
Three cases where you should walk away:
Your clients want one-and-done deep resurfacing. Buy CO2.
Your market is predominantly Fitzpatrick V–VI. Neither ablative platform is first-line. Start with 1550nm or RF microneedling.
You get fewer than 30 resurfacing enquiries a month. Idle equipment is the real cost, not maintenance.
Where a 2940 + 1064 platform fits
Dual wavelength changes the math. 2940nm covers superficial resurfacing. 1064nm covers pigment and vascular work. So one room serves two service lines, and the machine is not idle between resurfacing cases.
That is the configuration we build. It is why most of our buyers choose dual over single. But check the wavelength list against your own client mix first. If 90% of your revenue is resurfacing, a single-wavelength Er:YAG at a lower price is the better purchase. We will say so.
Results vary with skin type, device settings and operator technique. Nothing here is a substitute for a patch test and a trained clinician’s judgement.
Regulatory note
CE marking on aesthetic laser platforms usually covers LVD and EMC electrical safety. That is not Medical CE under EU MDR. The two are not interchangeable. Ask a supplier which certificate they actually hold — in writing. Confirm your own market’s import requirements before you order.