A carbon dioxide (CO2) laser for skin emits infrared light at 10,600nm, a wavelength water absorbs strongly. It vaporises a thin layer of tissue and heats the layer underneath, which is why clinics use it for resurfacing, atrophic scars, benign lesions and rhinophyma.
Search “CO2 laser”, though, and you’ll find as many machines for cutting plywood as for resurfacing faces. Even among skin lasers on the same wavelength, results can differ a lot, mostly because of how each device controls the pulse and how much heat it leaves behind.
This is the next guide in our technology series, after our Nd:YAG laser technology guide. If you’re weighing erbium against Nd:YAG instead, our guide to Er:YAG and Nd:YAG lasers covers that decision.
What is a CO2 laser?
A CO2 laser is a gas laser. Because skin is mostly water, its 10,600nm energy is taken up within a fraction of a millimetre of the surface. Delivered with enough intensity, it vaporises (ablates) the tissue it hits and leaves a thin zone of heated, coagulated tissue behind.
That combination defines the technology. Ablation removes tissue, while the residual heat seals small vessels and contracts collagen, hence CO2’s reputation for tightening and a drier treatment field. Other ablative lasers vaporise tissue too; what sets CO2 apart is how much heat it leaves behind, and how much of it a modern device lets you control. For the wider family, see our overview of ablative lasers.
How CO2 energy interacts with skin
Tissue only vaporises once enough energy arrives quickly enough. Because water absorbs 10,600nm less strongly than Er:YAG’s 2,940nm, CO2 needs considerably more energy per unit area to start ablating. Below that threshold, CO2 energy heats tissue without removing it.
Timing matters as much as energy. Keeping each interaction under about 1 millisecond, the thermal relaxation time of the upper skin, limits how far heat spreads during the pulse. In pig skin studies, CO2 pulses longer than 1ms raised the ablation threshold and increased residual thermal damage, although the researchers found irradiance, the power delivered per unit area, was the stronger predictor of tissue effect.
What’s left after each pulse is the residual thermal zone. In a split-face trial comparing the two ablative wavelengths, biopsies showed an average of about 90µm of residual thermal damage on the CO2 side (range 50 to 200µm), against about 45µm on the Er:YAG side (range 30 to 50µm). That zone is what coagulates small vessels and drives collagen contraction and remodelling. For why longer infrared wavelengths behave this way, see the key to high-energy wavelengths.
Fractional vs fully ablative CO2
Fully ablative resurfacing removes the epidermis across the whole treatment area. Fractional resurfacing ablates a grid of microscopic columns, known as microscopic treatment zones (MTZs), and leaves bridges of untreated skin between them. Manstein and colleagues introduced this concept, fractional photothermolysis, in 2004. Healthy tissue around each zone drives faster repair, and ablative fractional CO2 applies the same principle with a vaporised channel at the centre.
Pitch is the spacing between spots. Density is the share of the surface actually treated, set by spot size and pitch together. Tighten the pitch and density rises; open it and more untreated skin remains to heal from.
The HiScan SVR scanner on the MultiPulse® PRO shows how this works on a single device. Its pitch adjusts from 0 to 2,000µm across a scan area of up to 15 × 15mm. Close the pitch right down and the spots merge into confluent, fully ablative coverage; open it up and the same scanner delivers fractional treatment. Stacking, available over five levels, fires repeated pulses into the same point to take ablation deeper in measured steps.
When each approach is the right call
Fractional CO2 suits most resurfacing and atrophic scar work, where patients need a manageable recovery and a course of sessions is acceptable. Fully ablative treatment comes into its own for localised indications that need complete tissue removal, such as rhinophyma or lesion vaporisation. Healing time scales with the choice, as the recovery table below shows.
Why pulse shape matters
Two CO2 lasers with the same wavelength and power can produce very different tissue effects, depending on how each pulse delivers its energy.
Continuous wave (CW) output runs for as long as the footswitch is held. It heats steadily, which suits cutting and coagulation but is harder to control on facial skin. In a review of dermatological CO2 use, pulsed or scanned delivery limited the band of thermal damage to around 150µm, against around 400µm with a continuous wave beam.
Superpulse modes break that output into short pulses of much higher peak power, delivered in durations shorter than the skin’s thermal relaxation time. The limit is energy per pulse. If a single pulse doesn’t reach the ablation threshold, repeated pulses heat the tissue before they vaporise it, and the thermal zone grows. That’s why pulse energy matters as much as pulse length.
High-peak short-pulse modes, sometimes described as ultrapulse-style, go further. Single pulses of around a millisecond or less, at fluences of about 4 to 5 J/cm², can ablate cleanly with a thermal zone in the order of 50µm, according to research presented to SPIE.
Pulse shaping adds another layer. Rather than one fixed pulse profile, the device shapes each pulse to set how much energy goes into ablation and how much into heating the tissue below. Asclepion’s Dynamic Pulse Control (DPC) is one example, with four pulse shapes plus CW, ranging from a high ablation peak for clean surface work to shapes that add a deliberate heating phase for deeper remodelling. The MultiPulse® PRO page sets out what each DPC mode does and the indications it’s designed for.
See Dynamic Pulse Control on skin. Book a MultiPulse® PRO demonstration with our clinical team and compare pulse modes on the indications you treat. Book a demonstration
RF-excited vs DC-excited CO2 sources
CO2 tubes are energised either by direct current (DC) or by radio frequency (RF). RF excitation allows faster, more repeatable pulse switching, which matters when a device shapes each pulse, and sealed RF tubes are generally designed to run without gas refills. Independent comparisons of tube life come mainly from the industrial laser sector rather than medical devices, so ask any supplier for the stated tube life, the replacement cost and what the warranty covers. Asclepion cites stable pulse timing and a longer service life than conventional CO2 sources for the MultiPulse PRO’s RF source.
Clinical applications of CO2 lasers
Resurfacing
Fractional and fully ablative resurfacing address texture, fine lines and photodamage, with some tightening as well.
Atrophic and acne scars
Fractional CO2 is widely used for atrophic acne scarring, though scar type still decides the plan. Our guide to laser treatment for acne scarring matches devices to scar types, and our laser scar reduction guide covers the wider options.
Benign lesions
CO2 vaporises benign lesions precisely. The catch: vaporised tissue can’t reach histology. Diagnose first, and where there’s any uncertainty, biopsy or excise for histology before choosing vaporisation. In one series of 92 CO2 procedures on oral lesions, the team vaporised only lesions already confirmed by biopsy. That caution paid off: clinical diagnosis matched histology in just 94.8% of excised specimens, and one lesion diagnosed as a traumatic ulcer proved to be a squamous cell carcinoma.
Pigmented and melanocytic lesions need particular care. In one published case, a cheek lesion clinically diagnosed as a lentigo and treated several times with a CO2 laser later presented as metastatic melanoma.
Rhinophyma
Rhinophyma needs bulk tissue removal with good bleeding control. In a UK review of 124 patients published in the British Journal of Dermatology, CO2 treatment was completed in a single session for 115, and results were rated good to excellent in 118.
Periorbital lines and laser blepharoplasty
CO2’s coagulating effect suits incisional laser blepharoplasty and periorbital resurfacing. One histology study found eyelid epidermis regenerated within 7 to 10 days of CO2 resurfacing. Read more about laser blepharoplasty.
CO2 lasers and darker skin types
Post-inflammatory hyperpigmentation (PIH) is the main concern in Fitzpatrick IV to VI. The evidence is mixed rather than prohibitive. A retrospective study of fractional CO2 for acne scars in Asian patients with skin types III to IV recorded PIH in 73% of patients, lasting more than three months in 32%. A retrospective study of 57 Middle Eastern patients with skin types IV and V, using high-fluence treatment on individual scars and lower-fluence resurfacing across the wider area, reported no clinically significant PIH, although there was no control group and short-term side effects weren’t systematically recorded.
Density looks like the main lever, although the strongest evidence comes from non-ablative fractional lasers. In a study of Chinese patients, Chan and Manstein found that lower-density treatment had a lower incidence of PIH, and that low-energy, high-density settings produced the most. The same principle is widely applied to fractional CO2.
The two pigment risks behave differently. NHS guidance notes that darkening usually fades over 6 to 12 months, while skin made paler may stay that way.
In practice, that means conservative density and energy, a test patch, and an agreed pre and post laser care plan. On the MultiPulse® PRO, density is set through the HiScan SVR’s pitch, which opens up to 2,000µm, and the Randomized scan mode is designed to separate adjacent pulses and reduce localised heat build-up. Parameter choice for darker skin always rests with the treating practitioner.
Patient selection and contraindications
Isotretinoin is where guidance has moved. One NHS trust’s patient guidance asks for oral retinoids, including isotretinoin, to be stopped six months before CO2 treatment. A 2017 systematic review with consensus recommendations found insufficient evidence to justify delaying fractional ablative laser treatment in patients on or recently on isotretinoin, but did not recommend fully ablative laser during systemic isotretinoin treatment. Timing should follow the prescriber’s advice, the device’s instructions and the clinic’s protocol.
Recovery and downtime
Recovery depends on mode, energy, depth and density, so these ranges are typical, not promised.
| Recovery stage | Fractional CO2 | Fully ablative CO2 |
|---|---|---|
| Downtime | Around 5 to 7 days depending on depth, with pinpoint bleeding for the first 1 to 2 days | Around 7 to 10 days in a recent review. In a 1999 split-face trial, patients typically stayed home for about 2 weeks |
| Crusting and healing | Crusts usually clear within 1 to 2 weeks as the skin heals | Longer than fractional. Follow the clinic’s wound-care protocol |
| Redness | Moderate to marked for 1 to 3 weeks | Present on 95% of CO2-treated sides at 2 weeks, 62% at 2 months and 10% at 6 months in a split-face trial |
| Late pigment change | PIH is the main risk for both approaches, especially in darker skin, and usually fades over 6 to 12 months | PIH, plus delayed hypopigmentation that can appear months later and may be permanent |
Sources: Sebaratnam et al., Medicine Today 2023; Memorial Sloan Kettering; QVH NHS Foundation Trust; Khatri et al. 1999.
CO2 vs Er:YAG: which ablative laser fits your clinic?
Both wavelengths target water, but Er:YAG at 2,940nm is absorbed roughly 10 to 15 times more strongly than CO2. Short-pulse Er:YAG removes around 5 to 25µm per pass, depending on fluence, with very little residual heat, so it ablates in fine layers. CO2 deposits more heat, as the table shows. For a fuller look at fractional erbium against fractional CO2, see our erbium vs CO2 laser comparison.
| CO2 (10,600nm) | Er:YAG (2,940nm) | |
|---|---|---|
| Residual thermal zone | Up to 200µm in split-face histology | Up to 50µm in the same study |
| Bleeding control | Coagulates small vessels as it ablates | Less coagulation in cold ablation modes |
| Tissue effect | Ablation plus collagen contraction and tightening | Precise, layer-by-layer ablation |
| Downtime and side effects | Slower recovery; hypopigmentation on 43% of CO2 sides in a 1999 fully ablative trial | Faster recovery in the same trial; hypopigmentation on 5% of sides |
| Indications that favour it | Rhinophyma, lesion vaporisation, blepharoplasty, scars where tightening is wanted | Fine resurfacing, delicate areas, patients who prioritise a quick recovery |
Er:YAG isn’t purely cold either. Variable-pulse systems add a thermal component, and the Cool Laser by Dermablate® offers thermal modes alongside cold ablation.
Neither wavelength wins outright. A caseload leaning towards scars, rhinophyma, lesions and tightening favours CO2; one leaning towards fine resurfacing and fast recovery often suits Er:YAG. Some clinics run both. Compare the MultiPulse® PRO and Cool Laser, or read how Er:YAG compares with Nd:YAG.
How to choose the best CO2 laser for your clinic
There’s no single best CO2 laser. The right one covers your most demanding indication, gives you precise control of each pulse, and comes with the regulatory paperwork, training and UK servicing that keep it earning. Ask every supplier the same questions and get the answers in writing.
| What to check | Why it matters | Ask the supplier | MultiPulse® PRO |
|---|---|---|---|
| Laser source | Pulse stability and tube life drive consistency and running costs | RF or DC? Stated tube life, replacement cost and warranty cover | RF-excited CO2 source |
| Power | It must cover your most demanding indication, not your average one | Maximum output, and whether it’s available in the pulse modes you’ll use | 60W |
| Pulse control | Sets the balance between ablation and heat | Which pulse modes, and can each pulse be shaped? | Dynamic Pulse Control: four pulse modes plus continuous wave |
| Scanner | Sets the range from fractional to fully ablative | Pitch range, scan area, patterns and stacking | HiScan SVR: pitch 0 to 2,000µm, scan area up to 15 × 15mm, three scan patterns, five stacking levels |
| Handpieces | Lesions, blepharoplasty and small areas need full-ablation handpieces | Which handpieces are standard, and which cost extra? | 7.0″ handpiece as standard, with 1.5″, 2.0″, 4.0″ and collimated options. Spot sizes from 0.125mm to 2mm, with sterilisable spacers |
| Who will operate it | Proposed rules in England would limit ablative and periorbital laser work to doctors, dentists and independent prescribers | Does the training cover your operators, and do they meet the proposed requirements? | Class 4 medical laser for use by trained medical practitioners |
| UK regulatory status | You need a device legally placed on the UK market | UKCA or CE marking, and MHRA registration | CE marked under the Medical Device Directive 93/42/EEC and MHRA registered |
| Training | Outcomes depend on the operator as much as the device | Is clinical training included, and who delivers it? | Training through the Asclepion Academy is included, covering device operation, DPC parameter selection, scanner settings and technique, with ongoing clinical support |
| Service | Downtime costs revenue | UK engineers? Response times? Parts held in the UK? | A-List package with a 2-year warranty: one year of parts and labour, then one year of parts only. Handpieces carry a 1-year warranty. Technical service is handled by Asclepion UK in London, with remote support and service contracts available |
Medical-grade or budget: what the price difference buys
Search for a fractional CO2 machine and you’ll find systems at very different price points. The wavelength is the same. The differences sit in the parts that decide consistency, safety and running costs: the laser source and its stated life, how precisely each pulse can be controlled, the scanner’s range, the regulatory status that lets you use the device in a UK clinic, and whether training, servicing and parts are available in the UK. The table above is the quickest way to compare like with like.
How much does a CO2 laser machine cost?
Price depends on configuration more than wavelength. Source type, power, scanner and handpieces all move the figure, as do training, warranty and service. Compare quotes like for like, and include running costs over the device’s life: tube replacement, servicing, consumables such as smoke evacuation filters, and the revenue lost while a device is out of action.
Is a CO2 laser worth it for your clinic?
That depends on how many of its indications you’ll actually treat. A CO2 laser earns its place when one device covers several revenue lines: resurfacing, acne and surgical scars, benign lesions, rhinophyma and periorbital work. A clinic that mainly plans light resurfacing may be better served by Er:YAG, which offers faster recovery for those patients. Map your current and planned caseload against the indications above before you compare prices.
UK Class 4 laser requirements
Aesthetic CO2 lasers are Class 4, the highest hazard class. MHRA guidance sets out the framework most clinics follow: a Laser Protection Adviser (LPA) to advise on safety and risk assessment, local rules for each device, a Laser Protection Supervisor to oversee them day to day, and a register of authorised users. The guidance has no legal status itself and requirements differ between UK nations. In England, consulting an LPA is described as good practice and some local authorities require it, so check with your local authority before installation.
In Wales and Northern Ireland, private establishments using Class 3B or 4 lasers must appoint a certified LPA.
In practice, that also means laser-safe eyewear for everyone in the room, a dedicated smoke evacuation system for laser plume, and a risk assessment for the treatment room.
Regulation is moving, too. On 21 October 2026, the Department of Health and Social Care opened a consultation on restricting high-risk cosmetic procedures in England. Its proposals would limit lasers that remove layers of skin, and laser or IPL treatment on the eyelid or within the eye socket’s rim, to doctors, dentists, and nurses, midwives and pharmacists with independent prescribing qualifications, with the CQC enforcing. The consultation closes on 13 January 2027, and the proposals are not yet in force. Scotland’s Non-surgical Procedures and Functions of Medical Reviewers (Scotland) Act received Royal Assent on 12 May 2026.
Compare the MultiPulse® PRO against your caseload
If you’re comparing CO2 lasers, our team will take you through the MultiPulse PRO against the indications you treat, the pulse modes you’d use, and what the device would cost to run. Book a demonstration or explore the MultiPulse® PRO’s pulse modes and specifications.
Frequently asked questions
What wavelength is a CO2 laser?
A CO2 laser emits at 10,600nm, in the infrared. Water absorbs this wavelength strongly, so the energy is taken up close to the skin surface.
Is a CO2 laser ablative?
Yes. Above its ablation threshold, a CO2 laser vaporises tissue and leaves a thin coagulated zone behind. Below the threshold, it heats tissue without removing it.
What’s the difference between superpulse and continuous wave CO2?
Continuous wave emits steadily while the footswitch is held, so heat spreads into surrounding tissue. Superpulse delivers energy as short, high-peak pulses shorter than the skin’s thermal relaxation time. Provided each pulse carries enough energy to reach the ablation threshold, that gives cleaner ablation with less collateral heat.
Can CO2 lasers be used on darker skin types?
Selected patients can be treated, with caution. Fitzpatrick IV to VI carries a higher risk of post-inflammatory hyperpigmentation, and the studies cited here cover skin types III to V rather than the full range. Lower density, conservative energy, a test patch and planned aftercare reduce the risk but don’t remove it, so suitability is a clinical decision for each patient.
Which has more downtime, CO2 or Er:YAG?
Usually CO2, when the two are used at comparable depth. In a split-face trial of fully ablative resurfacing, the Er:YAG side recovered more quickly, with significantly less redness at 2 and 8 weeks. Fractional delivery shortens recovery for both.
How much does a CO2 laser machine cost?
It depends on configuration. Source type, power, scanner, handpieces, training, warranty and service all affect the price. Compare quotes like for like, including running costs such as tube replacement and servicing over the device’s life.
Who can use a CO2 laser in the UK?
It currently depends on the UK nation and local authority, with MHRA guidance recommending a Laser Protection Adviser, local rules and a register of trained, authorised users. In England, a government consultation opened on 21 October 2026 proposes limiting lasers that remove layers of skin, and laser treatment on the eyelid or around the eye, to doctors, dentists and independent prescribers. These proposals are not yet in force.
What is the best CO2 laser for a clinic?
There’s no single best machine. The right CO2 laser covers your most demanding indication with stable, shapeable pulses, a scanner that moves between fractional and fully ablative treatment, the handpieces you need, UK regulatory approval, and training and servicing in the UK. Compare suppliers on those points, not on headline power alone.
How many fractional CO2 sessions are needed for acne scars?
Most patients need a course rather than a single session. Published acne scar studies have used one to three sessions, and up to four sessions six to eight weeks apart in darker skin types, with scar type deciding the plan.
