{
“@context”: “https://schema.org”,
“@graph”: [
{
“@type”: “MedicalWebPage”,
“name”: “Cold Laser vs Class IV Laser — What’s the Difference?”,
“about”: [
{
“@type”: “MedicalTherapy”,
“name”: “Photobiomodulation”,
“alternateName”: [“Cold Laser Therapy”, “Low-Level Laser Therapy”, “LLLT”, “PBM”]
},
{
“@type”: “MedicalTherapy”,
“name”: “High-Power Laser Therapy”,
“alternateName”: [“Class IV Laser Therapy”, “HPLT”]
}
],
“lastReviewed”: “2026-04-28”,
“reviewedBy”: {
“@type”: “Person”,
“name”: “Dr Sam Johnson”,
“jobTitle”: “Chiropractor”,
“alumniOf”: [
{ “@type”: “CollegeOrUniversity”, “name”: “Macquarie University” }
]
}
},
{
“@type”: “FAQPage”,
“mainEntity”: [
{
“@type”: “Question”,
“name”: “What is the difference between cold laser and hot laser?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Cold laser (super-pulsed) delivers very short, high-energy bursts of light that produce no heat in the tissue. The primary mechanism is photochemical — light is absorbed by cells to trigger biological responses. High-power Class IV lasers deliver continuous energy at higher average power, which creates thermal effects in the tissue. Both have clinical applications, but they work through different mechanisms.”
}
},
{
“@type”: “Question”,
“name”: “Is Class IV laser more powerful and therefore better?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Higher power does not automatically mean better clinical outcomes. Research suggests that the therapeutic effect of photobiomodulation is photochemical, not thermal. The Arndt-Schultz principle and biphasic dose response indicate that there is an optimal therapeutic window — too little energy has no effect, but too much may be inhibitory. The majority of positive photobiomodulation trials used parameters consistent with lower-power and super-pulsed devices.”
}
},
{
“@type”: “Question”,
“name”: “Does cold laser therapy hurt?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “No. Cold laser therapy produces no sensation of heat and is non-invasive. Most patients feel nothing during treatment, though some report a mild tingling. The device can be placed directly on the skin without risk of burns. It is classified as a Class 1M laser, which means it meets the highest safety classification for consumer exposure.”
}
},
{
“@type”: “Question”,
“name”: “Which type of laser therapy has more research behind it?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “The vast majority of the 700-plus randomised controlled trials in photobiomodulation used Class 3B or super-pulsed lasers, not Class IV devices. Class IV laser therapy is a newer application and its dedicated evidence base is still developing. Both approaches have published research, but the depth and breadth of evidence is currently stronger for lower-power and super-pulsed parameters.”
}
},
{
“@type”: “Question”,
“name”: “Can I get burned by cold laser therapy?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “No. A 2015 study (Grandinetti et al., PMID: 25987340) tested the Multi-Radiance super-pulsed laser at multiple doses across all skin types and found no significant skin temperature increases. The device is classified as Class 1M — the same safety classification as a laser pointer. It can be held stationary on the skin without any risk of thermal injury.”
}
},
{
“@type”: “Question”,
“name”: “Why does your device use multiple wavelengths?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Different wavelengths of light interact with different tissue depths and biological targets. Our super-pulsed laser uses four wavelengths — 455 nm (blue), 660 nm (red), 875 nm (infrared) and 905 nm (super-pulsed infrared) — to target tissues from the skin surface down to deeper structures. Each wavelength is sequenced so that shallower wavelengths prepare the tissue pathway for deeper ones.”
}
},
{
“@type”: “Question”,
“name”: “What does super-pulsed mean?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Super-pulsed means the laser fires in extremely short bursts — each lasting roughly 100 to 200 nanoseconds — with long rest periods between them. During each pulse, peak power reaches 50,000 milliwatts, but because the pulses are so brief and the duty cycle is approximately 0.001%, average power stays very low. Think of it like a camera flash compared to a desk lamp — the flash delivers intense light for an instant without generating heat.”
}
},
{
“@type”: “Question”,
“name”: “Is one type of laser therapy safer than the other?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Both types are used clinically and both have established safety protocols. However, there are practical differences. Class IV lasers carry thermal risk if not moved continuously, require mandatory laser safety eyewear for the patient and all personnel, and typically need dedicated treatment rooms with door interlocks and warning signage. Super-pulsed Class 1M devices carry no burn risk, do not require protective eyewear at treatment distances, and have no special room requirements.”
}
},
{
“@type”: “Question”,
“name”: “What device do you use?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “We use the our clinical-grade super-pulsed laser, a super-pulsed Class 1M laser that is TGA-registered and FDA 510(k) cleared. It delivers four simultaneous wavelengths plus a static magnetic field. The device weighs 250 grams, is cordless, and can be applied directly to the skin without any thermal risk.”
}
},
{
“@type”: “Question”,
“name”: “How do I know which type of laser my practitioner uses?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Ask your practitioner directly. Key questions: What is the laser classification? What is the average power output? Does it require protective eyewear? If the answer is Class IV and above 500 milliwatts average power with mandatory eyewear, it is a high-power thermal laser. If it is Class 1M or Class 3B at lower average power with no eyewear required, it is a cold laser or low-level laser device.”
}
}
]
}
]
}