“I’m scared to use my laser/IPL.” Why?

I’ve heard this comment many times from laser/IPL users, through the years. It is perfectly understandable – most people don’t want to hurt or injure their clients. For all sorts of reasons…

In particular, they are scared of “burning” their clients. They are scared that they might not use their equipment correctly or use the wrong protocols.

The main reason for this fear usually comes down to a recurring issue – how to choose the correct settings on your device! If they are ‘too high’ then the risk of damaging the skin is also high. (Click here for a document I wrote to explain how to do this properly).

So, as a consequence, many users ‘turn it down’ so that the risk of skin damage is significantly lower. But…. the likelihood of a successful treatment result is also significantly lower!!

The fact is, the higher the fluence at the skin surface, the higher the chances of a successful outcome. It’s that simple.

But, the risk of unwanted thermal damage is also higher.

So how do we get around this conundrum of achieving good, repeatable results by using higher fluences without scarring our clients?

The answer lies in proper cooling – before, during and after the application of the light energy.

The importance of fluence

Let’s go back to basics. What are we trying to do with these laser/IPL treatments?

In essence, we are trying to ‘cook’ something – usually proteins in the hair or blood vessels or pigmentation. This requires heating them. We do this by firing light energy at them, which is preferentially absorbed, thereby generating heat energy. This translates into a rise in temperature in the targets.

However, calculations show that less than 10% of the energy we fire at the skin actually does the job!! More than 90% of it is excess to requirements. But that energy has to ‘go somewhere’. If left unattended, this excess heat energy will remain in the skin (which is 70% water and very conductive, unlike the air) and will potentially start ‘cooking’ other proteins like collagen.

So the trick is to encourage the heat energy to leave the skin as quickly as possible. We can do this by applying anything cold at the skin surface. This can be cool air, ice packs, cold compresses or IPL tips.

I now train IPL users to ‘pre-cool’ the skin for about 1 to 2 seconds to protect the epidermis and reduce the thermal pain sensation. After firing the energy pulse, I train them to keep the cold IPL tip on the skin for at least 2 or 3 seconds – this cold (often icy) tip will suck much of the excess heat energy out of the skin, before it has a chance to damage the dermis, or epidermis.

After the treatment area has been covered, I suggest applying cold ice packs to it, to keep drawing as much heat from the skin as possible.

Bu using this technique, it is possible to apply higher fluences without damaging the skin. It also feels much more comfortable, since the thermal pain receptors are pre-cooled before the light is delivered.

It is very easy to test this technique on yourself – the photo above shows two IPL shots on my own forearm taken only minutes after a couple of practice shots. We used a 530nm filter with a fluence of 40 J/cm2 in a 35 ms pulsewidth. One spot had a 2 second pre-cool, while the other had no pre-cooling. The difference in sensation was significant (ouch!!).

Sub-surface vascular damage is evident along with some pigmented damage. However, I applied an ice pack to my arm for about 15 minutes after the treatment. While both areas exhibited a ‘stinging’ sensation immediately after the treatment, this disappeared completely after the ice packs.

There is no significant tissue damage today (four days after treatment) and there was no blistering or epidermal damage. There has been no further sensation on these areas since the ice cooling. While it may appear so, this tissue is NOT ‘burnt’! This is what I would expect to see after such a high fluence.

While the areas may appear ‘damaged’, they are not. The only damage has been to the pigmentation (freckles) and some transient capillary damage. I expect this all to resolve in the next week to ten days.

I have no problem delivering high fluences to the skin – I once used a 100 J/cm2 fluence on a client with very deep follicles, with no problems at all. I also applied a lot of cooling!

So, don’t fear your equipment. Don’t be afraid to use higher fluences – they produce better results. But, do make sure you apply sufficient cooling before, during and after the application of the light energy to minimise any unwanted damage.


In summary, the chances of a successful clinical outcome depend greatly on the applied fluence. Higher fluences will generate greater tissue responses, but also greater risk of thermal damage. So more cooling is also required. It’s a balance – the high the fence, the more cooling you must use – during and after the treatment!

Hope this helps,


PS If you would like some training from me, email me at mikemurphyLPA@gmail.com. Or, you might want to attend one of my Masterclasses which I’m planning to hold next year.

PPS Please note that the above does NOT apply to laser tattoo removal. Always use low fluences for that process.

5 thoughts on ““I’m scared to use my laser/IPL.” Why?

    1. Hi Nabil,

      The “ms” you refer to the is the ‘pulsewidth’ of the device. This is the length of time that the pulse of energy is ‘ON’. In essence, this is how long you will be ‘cooking’ the targets. So, a longer pulsewidth will cook for a longer time than a shorter pulse.

      Imagine baking a cake – you need to set your oven to the correct temperature first (that’s the ‘fluence’) then you must cook your cake for the correct length of time (that’s the ‘ms’).

      Does that make sense?


  1. We primarily perform tattoo removal treatments. We use-and have always used- cold air chilling before, during and after treatment. That said, I seldom use a setting that exceeds 2.6J on a Quanta Q+ for first treatments. I do increase power settings on subsequent treatments. Power settings are not asymptotic, but I usually do not need to increase them past 6J.

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