When I was running my own shop, for years on Staff Appreciation Day, my partner and I would shut down the office, rent out an entire spa, and treat our mostly female staff for  manicures and pedicures, or any service they wanted—a welcome break from the daily grind of personal injury work. My staff had the best fingernails (and toenails) in the city!

Perhaps not coincidentally, I often had potential clients walking in with complaints of salon-related injuries, and over time I developed a mini-specialty in handling those cases.

A few stand out.

One involved a client who alleged a scalp burn from a chemical product, followed by severe psychological injury when hair loss and scarring set in.

Another centred on permanent scarring after a so-called “hot rock” treatment that was anything but controlled.

Another involved alleged permanent hair loss after a reaction to a salon-applied treatment, where the salon pointed the finger directly at the product manufacturer.

The legal fights were never simple.

The hard part isn’t proving someone was hurt. Photos, client testimony, and specialists handle that. The hard part is pinning legal responsibility on the right defendant. The salon for application, warnings, screening and after-care, or the manufacturer for defect, formulation, labelling and warnings. In Ontario, that split drives everything—pleadings, experts, discovery strategy, and settlement posture.

Despite the volume of beauty salon and spa treatments performed across Ontario every day, I have found that remarkably few reported cases make their way into the courts. I believe there are several reasons for this. Most claims are relatively low in dollar value compared to the cost of litigation, making them prime candidates for early settlement or resolution in Small Claims Court, where decisions are rarely get published.

Insurers also tend to resolve these files quietly to avoid publicity and expert costs that can easily dwarf the damages at issue. Add to that the evidentiary complexity of separating salon negligence from product liability, often requiring duelling dermatologists, chemists, or engineers, and many plaintiffs and defendants alike choose settlement over protracted proceedings. The result is a dearth of appellate guidance, leaving practitioners to extrapolate from general negligence principles and the occasional medi-spa or cosmetic-treatment case that does reach the Superior Court.

The framework: negligence, not strict liability

Ontario law doesn’t impose strict liability on salons or product makers for these injuries. Instead, liability is grounded in negligence, breach of contract, or statutory duties, depending on the context. Courts have repeatedly emphasized that product liability in Canada is fault-based, not strict. See for example Hollis v. Dow Corning Corp., [1995] 4 S.C.R. 634, where the Supreme Court of Canada confirmed that manufacturers owe a duty to warn but are not strictly liable for injuries caused by their products.^[1]

Plaintiffs must prove fault—typically negligent application, inadequate screening/patch testing, poor after-care instructions, or failure to warn. Salons are “occupiers,” so ordinary negligence principles and the Occupiers’ Liability Act^[2] govern the premises and how services are delivered. But it’s still a reasonableness standard, not insurer-level responsibility. When products are implicated, you’re into products-liability negligence (design/manufacture/warnings) and, in many cases, contractual and consumer-protection theories if the product was sold. None of that is strict liability in the classic sense.

Waivers and “consent” aren’t a get-out-of-jail-free card

A frequent defence in spa/medi-spa files is the signed “consent/waiver” form^[3]. Ontario courts are rightly skeptical when a waiver is used to sidestep careless treatment. In Rush v. De Ruiter, 2018 ONSC 1210^[4], the Court refused to throw out a negligence claim arising from cosmetic light-based therapy despite a signed release. The judge treated it as a medical-negligence style claim and would not allow a waiver to bar liability for substandard care. A practical takeaway for salons and medi-spas is that you can’t contract out of the duty to take reasonable care with potentially injurious treatments. Good screening, warnings, settings, supervision, and after-care still matter^[5].

Salon vs. manufacturer: who should pay (and in what share)?

In chemical-injury and hair-loss files, plaintiffs usually sue both the salon and the product maker (sometimes the distributor) and let discovery sort out causation and apportionment.

Where salons lose:

I believe that salons tend to lose cases when the mistakes are rooted in their own process rather than the product. Application errors are the most obvious example—using the wrong mix, leaving a product on for too long, setting a device at the wrong temperature, or ignoring the manufacturer’s instructions for use. Skipping a patch test where one is recommended, or failing to monitor the client properly during the procedure, only compounds the problem. Pre-service screening is another common weak spot. When salons don’t ask about a client’s history of reactions, existing dermatological issues, medications, or recent treatments such as colouring or bleaching, they leave themselves exposed to claims that the injury could have been anticipated and avoided. Finally, liability often comes down to communication after the fact. If clients aren’t warned about the specific risks of the procedure, told what to expect in terms of downtime, or given clear instructions on when to escalate if burning or tingling intensifies, I think that courts are far more likely to conclude that the salon fell below the standard of care.

Where manufacturers get pulled in

Manufacturers tend to be drawn into these cases when there is evidence that the product itself was at fault rather than the way it was applied. One avenue is a formulation or defect theory, where the product is shown to have deviated from its specifications or become contaminated. These cases underscore the importance of preserving the actual bottle and lot number early on to allow for proper testing. More commonly, manufacturers face scrutiny under a duty-to-warn theory. If the product’s label is vague, if contraindications are missing, or if the instructions for use are so poorly drafted that misuse is foreseeable even by someone who follows them, liability can attach. But even then, the law in Ontario frames this as fault-based negligence, not strict liability, meaning plaintiffs must still prove that the manufacturer failed in its duty rather than relying on the mere fact of injury.

Apportionment reality

Even with a “hot” product, courts and insurers will ask a blunt question—would proper screening, a patch test, conservative settings, and prompt rinse/neutralization have avoided the injury? If yes, the salon’s share may dominate.

If the salon followed everything to the letter and the label was thin or misleading, the manufacturer’s slice grows. Ontario’s Negligence Act^[6] lets judges apportion fault across defendants. Your file prep should anticipate both theories from day one.

Proving it: evidence that actually moves the needle

Proving liability in a salon injury case is tricky. It ultimately comes down to evidence that holds up under scrutiny. The starting point is the product itself. The client I had with the scalp chemical burn had the wherewithal to insist that she would not leave the salon without the bottle. That won the day.

If you are advancing a defect or formulation theory, it is essential to preserve the same bottle and lot number, along with the labels, MSDS/SDS^[7], and instructions for use. Photographing fill levels and sealing the product for storage establishes a reliable chain of custody and avoids credibility gaps later. Beyond the product, the service records tell their own story. Detailed notes about formulas and mixes, timing of applications, device settings, temperature logs, and even who supervised each step of the treatment can be pivotal in showing whether the salon met the standard of care.

The client’s intake and consent paperwork is another key element. A file that carefully records allergies, prior reactions, medications, and skin or hair history gives the salon a stronger defence. A form that is blank or generic tends to undermine credibility and suggest shortcuts. Patch testing evidence can also move the needle. The question isn’t just whether a patch test was done, but whether it was meaningful—using the same product, at the same strength, on an appropriate test site.

Medical and dermatological evidence anchors the claim in science. Prompt presentation to a physician or dermatologist, findings that match the alleged mechanism of injury—whether contact dermatitis, a thermal burn, or alopecia—and an informed prognosis on whether regrowth is possible or the injury will result in scarring alopecia, all add significant weight.

Finally, if psychological injury is part of the claim, it must be tied closely to the medical evidence. Psychiatric opinions carry real value where the plaintiff’s narrative includes embarrassment, anxiety, or depressive symptoms stemming from visible hair loss or scarring, but claims should be kept proportional to the medical reality.

Consent, standard of care, and the “don’t judge by the outcome” principle

Ontario courts routinely caution against outcome-driven reasoning in professional negligence.

In practical terms, bad outcome does not equal negligence if the process met the standard of care. However the corollary is that good paperwork does not equal a defence if the process was sloppy. For cosmetic/medi-aesthetic settings, the line from Rush is clear—waivers won’t sanitize negligent execution. Ontario appellate courts also emphasize articulating standard-of-care in process terms (what a prudent practitioner does to identify risks and avoid them), not perfection by hindsight (See Armstrong v. Ward 2021 SCC 1^[8]).

For Plaintiffs

For plaintiffs, the most effective approach is to cast the net wide at the outset. That means naming both the salon and the manufacturer from the start and making sure the product and lot information are preserved immediately. The medical evidence should be front-loaded, particularly in cases involving hair loss, scarring, or significant psychological fallout. Dermatological opinions anchor the claim in science, while psychiatric assessments help establish the real-world impact on confidence, anxiety, or daily functioning. The theory of negligence needs to be tied to specific departures from the standard of care. For example, no patch test where one was indicated, failure to follow the manufacturer’s instructions, applying excessive heat or leaving chemicals on too long, or failing to provide adequate after-care advice. Plaintiffs must also anticipate the finger-pointing that inevitably comes. In my experience, salons tend to argue that any harm came from the product itself, while manufacturers insist the issue was in the way it was applied. Building both bridges early—application negligence on the one hand and product failure or inadequate warning on the other—ensures that the case does not collapse into a battle of deflection.

For Salons and Spas

For salons and medi-spas, the best defence begins long before a claim is ever filed. Consent should never be treated as a box to tick or a hurried signature. It is part education and part screening. Properly done, it involves meaningful discussion with the client, patch testing where appropriate, and careful documentation of settings, times, and staff involvement. Staff need to be trained not just in the routine procedure, but in recognizing contraindications and knowing when to stop. If burning or discomfort goes beyond what is reasonably expected, the service should be halted immediately, and the intervention documented. Keeping lot numbers and instructions for use on file is another simple but powerful safeguard. If a salon can show that it followed the manufacturer’s instructions precisely and trained its staff to do the same, it gains leverage in the event the manufacturer is blamed. What salons cannot do is rely on waivers to insulate them from negligence. As the court made clear in Rush, a signed release does not excuse substandard care.

Bottom line

Salon liability cases live or die on fault—in how the service was delivered and what was communicated—not on the mere fact of injury. Ontario courts don’t do strict liability here. If the salon’s process (screening, patching, settings, monitoring, after-care) was careful and the product label was robust, the manufacturer claim will be tough. If the product’s warnings were thin or the chemistry was off, the salon shouldn’t be the only target. Build the record from day one to show who actually failed the reasonableness test—and expect the salon and the manufacturer to split the bill accordingly.