Skin cooling in laser treatments: cold air, contact cooling and comfort
In laser treatments, skin cooling determines comfort, safety and the energy that can be used. This page explains what cold does in the skin, how cold air, contact cooling via sapphire and cooling gel differ and what pre-cooling, parallel cooling and post-treatment cooling mean. It also covers the particular features of tattoo removal, CO2 laser and RF microneedling and the question of when too much cold does harm.
The examples used are the KYROMASTER from SIACSKIN, a cold-air device reaching down to minus 50 °C without consumables, and lasers with built-in cooling such as the DEWEON 4LD and the AlexDUAL UFO.
What happens in the skin when it is cooled during laser treatment?
Cooling lowers the temperature of the epidermis before the laser pulse passes through it and so creates a buffer against overheating. On its way to the hair root, pigment or vessel, the light has to pass through the epidermis, whose melanin absorbs part of the energy. If the epidermis starts out cooler, it remains below the temperature at which blisters and pigment changes occur even after the pulse. The cold barely reaches the target at depth, which heats up as planned. In addition, cold dampens the transmission of pain stimuli.
For this purpose the DEWEON 4LD cools via a sapphire in the handpiece at down to minus 50 °C. The KYROMASTER cools without contact using cold air down to minus 50 °C.
Cold air, contact cooling or cooling gel: which type of skin cooling suits which laser?
Contact cooling suits devices whose handpiece rests on the skin, cold air suits all procedures without skin contact, and cooling gel is a supplement, not a substitute. A cooled sapphire window draws off the heat exactly at the site of the pulse, typically with diode lasers and broadband light. Cold air flows freely over the treatment area and is suitable for solid-state lasers, tattoo removal, fractional lasers and anything that works at a distance. Gel improves the coupling of light and cold, but warms up quickly on the skin and on its own cools only briefly.
At SIACSKIN, the DEWEON 4LD and the DERMAFORCE BBL PRO have sapphire contact cooling. The KYROMASTER supplies cold air and is suitable for alexandrite, diode, BBL and IPL, CO2, picosecond, Nd:YAG and RF microneedling.
What do pre-cooling, parallel cooling and post-treatment cooling mean in laser treatment?
The three terms describe the timing of cooling: before the pulse, during the pulse and afterwards. Pre-cooling lowers the starting temperature of the epidermis and dampens the sensation of pain; a few seconds per area are usually enough. Parallel cooling dissipates heat while the energy is arriving. It matters above all with long pulses, because the epidermis can then give off heat during the pulse itself. Post-treatment cooling absorbs the residual heat that migrates back from the depth to the surface and limits redness and swelling.
The KYROMASTER from SIACSKIN covers all three phases: cold air down to minus 50 °C as pre-cooling, parallel cooling and post-treatment cooling. You therefore cool with one device throughout the whole session without reaching for cold packs in between.
How much does skin cooling reduce pain during laser treatment?
Cooling takes away much of the sharpness of the laser pulse, but it cannot eliminate the sensation entirely. Cold slows conduction in the pain fibres of the skin, and the cold stimulus itself masks the heat stimulus. For most people, a stinging pulse becomes a brief, easily tolerable pinch. How strong the effect is depends on the area, hair density, energy and individual sensitivity. The difference is most marked on the upper lip, intimate area and shin.
The KYROMASTER cools with cold air down to minus 50 °C even before the first pulse. With the DEWEON 4LD, the cold sapphire rests directly on the skin; the AlexDUAL UFO has built-in compressor and quadruple cooling. For very sensitive clients, cold air can be used in addition.
Can higher laser energies be used with good skin cooling?
Yes, effective cooling extends the upper margin, because the epidermis tolerates more energy before it is damaged. Many treatments fail not because of the device's power but because the epidermis cannot withstand the necessary fluence or the client does not tolerate it. With a cold epidermis, it is possible to get closer to the energy the target actually needs, especially in darker skin types. The limit continues to be set by the skin reaction: cooling also dampens warning signals such as burning. You therefore increase in small steps and observe the skin after every pass.
The DEWEON 4LD combines 6000 W of total power with sapphire cooling down to minus 50 °C. The KYROMASTER adds cold air for devices without contact cooling.
What does the figure of minus 50 °C on a cooling device mean and how cold does the skin get?
The figure describes the temperature of the cold air or the cooling element, not the temperature of your skin. The skin is supplied with blood and constantly delivers fresh heat, so it cools only at the surface and only gradually. How cold it gets is determined by distance, air volume and duration. The aim is an epidermis that is markedly cooled but never frozen. A low starting temperature of the device above all means reserve: the cooling effect remains stable even at a high pulse repetition rate and in long sessions.
The KYROMASTER works with cold air down to minus 50 °C. You control how much of this reaches the skin via distance and duration. The sapphire in the handpiece of the DEWEON 4LD likewise reaches down to minus 50 °C.
Can the skin be cooled too much during laser treatment and what are the consequences?
Yes, too much cold can damage the skin itself and weaken the treatment. If an area is cooled for too long or from too short a distance, there is a risk of cold injury: whitish, numb areas, later redness, blisters or pigment spots, especially in darker skin types. There are also two effects on the result. Cold constricts fine vessels, so in the treatment of thread veins and redness the target shrinks. And very superficial pigment is cooled along with the skin and responds less well. Moreover, intense cooling masks the skin's warning signals.
The rule is therefore: keep the nozzle moving, keep your distance, never linger in one place. The KYROMASTER supplies cold air down to minus 50 °C. You use this reserve in measured doses, and rather sparingly for vascular treatments with the DERMAFORCE BBL PRO.
Is a laser's built-in cooling enough or do I also need a cold air device?
For hair removal, good built-in cooling is generally sufficient; a cold air device is worthwhile for procedures without skin contact and for sensitive areas. The decisive question is whether your laser cools the skin itself at all. Handpieces with a sapphire cool the treated site directly. Lasers for tattoo removal, fractional lasers and RF microneedling usually come with no skin cooling or only limited skin cooling, and there cold air closes the gap.
The DEWEON 4LD cools via sapphire at down to minus 50 °C; the AlexDUAL UFO has compressor and quadruple cooling and does not need an external cooling device. The KYROMASTER adds cold air for the other devices in the room and for areas such as the upper lip or intimate area.
Cold air or cold pack: how do you cool the skin properly during tattoo removal?
Ideally with cold air flowing over the tattoo before, during and after the pulses. In tattoo removal the handpiece does not rest on the skin, so contact cooling is ruled out. A cold pack can only be applied beforehand and afterwards, warms up quickly and afterwards lies on an irritated area that often shows pinpoint bleeding. Cold air cools without contact and therefore hygienically, exactly where the laser is being applied. After the session, cooling continues for a few more minutes, which dampens burning and swelling. At home, a cold pack in a clean cloth is sufficient.
The KYROMASTER is suitable for picosecond and Nd:YAG lasers and thus accompanies the PICOLO XL, the PICOLO L and the PICOLO S.
How do you cool the skin with the fractional CO2 laser when skin contact is not possible?
With the fractional CO2 laser, cold air is used for cooling, because the scanner works at a distance and the skin is open afterwards. Gel or a cooled window is out of the question: the wavelength is absorbed by water, so anything moist on the skin would intercept the energy. Cold air runs alongside during lasering and takes away the sensation of heat, which remains perceptible even after a numbing cream. Immediately afterwards it helps against the burning of the first few minutes. You direct the airflow from the side so that it does not drive the smoke towards you and the extraction continues to work.
The KYROMASTER is suitable for CO2 lasers and therefore goes with the FRACO CO2 XL, in CoolPeel mode as well as for full resurfacing.
When is cooling applied in RF microneedling: before, during or after the needle pulses?
In RF microneedling, cooling is applied above all directly after each treated field and at the end of the session, and beforehand too if desired. Here the heat is generated at depth at the needle tips and is meant to act there, so the surface does not need to be protected from the energy to the same extent as with a laser. Cold serves comfort: it dampens the needle insertion, takes away the sensation of heat and calms redness and swelling. Prolonged pre-cooling is not necessary; a numbing cream achieves more before the session.
For this purpose the EUPHEUS M8 comes with a Cold Hammer, with which you cool the treated areas after needling. The KYROMASTER is likewise suitable for RF microneedling and supplies cold air continuously without touching the freshly treated skin.
Does skin cooling replace numbing cream before laser treatment?
For hair removal and most light treatments, yes; for ablative lasers and deep RF microneedling, no. Cooling works immediately, but only at the surface and only for as long as it is running. A numbing cream usually needs 30 to 45 minutes to take effect but reaches deeper nerve endings. For short pulses on intact skin, cold is almost always enough. With the fractional CO2 laser, with needle depths of several millimetres and with tattoo removal on sensitive areas, the two complement each other: cream beforehand, cold air during and after treatment. The cream is removed completely before the first pulse.
The KYROMASTER supplies the cold air for this, down to minus 50 °C and without consumables. It goes with the FRACO CO2 XL just as well as with the EUPHEUS M8.
How do you guide the cold air nozzle correctly during laser treatment?
The nozzle is aimed at the treatment area at an angle from a distance of a few centimetres and constantly runs ahead of and behind the handpiece. In this way every site receives cold before and after the pulse without any one point becoming chilled. Keep the nozzle moving, never cool the same area for several seconds and, on the face, do not direct the airflow at the eyes or nose. For treatments with gel, blow at a shallow angle across the skin so that the gel does not dry out. Those working alone guide the nozzle with their free hand.
The KYROMASTER supplies cold air down to minus 50 °C for pre-cooling, parallel cooling and post-treatment cooling. How you integrate cooling into the workflow with your laser is part of the device training from SIACSKIN.
How long and with what do you cool the skin at home after laser treatment?
At home, you cool several times for 10 to 15 minutes in the first few hours, with a cold pack in a clean cloth or with cool, damp compresses. Ice and frozen packs never belong directly on the skin; the freshly treated area is more sensitive to cold than usual. After hair removal the sensation of warmth has usually passed within 1 to 2 hours; after tattoo removal or fractional laser it can last until the evening. During this time, avoid hot showers, sauna and exercise. If severe burning persists until the next day or blisters form, contact the studio and have the area examined by a doctor.
In the studio, the KYROMASTER takes care of post-treatment cooling directly after the session. Which care is suitable afterwards is set out in the SIACSKIN Aftercare Guide.
What are the running costs of a cold air device compared with cryogen spray and cooling gel?
In operation, a cold air device incurs practically only electricity costs, whereas cryogen spray and gel are used up with every treatment. Cryogen spray cools very precisely, but every session costs gas from cartridges that have to be repurchased and stored. Gel and cold packs are inexpensive but take time to apply, remove and pre-chill, and they cool unevenly. After a short lead time, cold air is available continuously, for every area and for several devices in the same room.
The KYROMASTER from SIACSKIN works without consumables and is suitable for alexandrite, diode, BBL and IPL, CO2, picosecond, Nd:YAG and RF microneedling. One cooling device thus accompanies your entire fleet of devices, including later purchases.
