The product that put cosmetic hypochlorous acid on the US map and the foundation Tower 28's whole brand was built around. Four ingredients — saltwater plus hypochlorous acid — used to address acne, eczema, rosacea, post-procedure recovery, and just about any skin condition where bacterial overgrowth or barrier inflammation is a factor. Pricey for what it is, but uniquely well-tolerated.
SOS Daily Rescue Facial Spray
The product that put cosmetic hypochlorous acid on the US map and the foundation Tower 28's whole brand was built around. Four ingredients — saltwater plus hypochlorous acid — used to address acne, eczema, rosacea, post-procedure recovery, and just about any skin condition where bacterial overgrowth or barrier inflammation is a factor. Pricey for what it is, but uniquely well-tolerated.
Score Breakdown
The most universally tolerated antimicrobial product on the market, with a four-ingredient formula and broad clinical backing for the active. Strong score across all dimensions; the price is the only honest weakness.
Data Confidence: high
On the market since 2020 with tens of thousands of reviews on Sephora and the Tower 28 site. Hypochlorous acid is one of the most well-studied antimicrobial molecules in dermatology, with decades of clinical wound-care literature behind it.
0/100
Overall Score
Ingredient Quality 0
Value for Money 0
Suitability Breadth 0
Irritation Risk (↑ = safer) 0
Assessment
Pros
- Four-ingredient formula — essentially hypochlorous acid in saline
- Clinically validated antimicrobial active with decades of wound-care use
- Safe on broken skin, sensitive skin, eczema, and post-procedure recovery
- Pregnancy-safe and gentle enough for children
- Calms inflammatory acne, rosacea flushing, and barrier-related redness
- Universal compatibility with other skincare actives, including retinol
- National Eczema Association accepted and Allure Best of Beauty winner
Cons
- Expensive for what amounts to saltwater plus an antimicrobial
- Subtle, cumulative effect — not a dramatic single-step treatment
- Faint chlorine note bothers some users
- Aluminum aerosol nozzle can leak in transit
Full Review
There is a particular kind of skincare product that becomes culturally important not because it's complicated, but because it's correct. The Tower 28 SOS Daily Rescue Facial Spray is one of those. The formula is four ingredients long: electrolyzed water, sodium chloride, sodium hypochlorite, and hypochlorous acid. That is the entire thing. There is no glycerin, no botanical extract, no preservative system, no fragrance. It is functionally saltwater that has been processed to generate hypochlorous acid, and that minimalism is not a marketing position — it's the actual product. The spray exists because Amy Liu, who founded Tower 28 in 2019 because her own eczema made most cosmetics unwearable, was using hypochlorous acid wound-care products from clinical brands and decided the same thing should be available in a format that didn't look like it came from a hospital supply catalog.
The ingredient is interesting enough to deserve a paragraph on its own. Hypochlorous acid (HOCl) is the antimicrobial molecule that human neutrophils produce as part of the immune response to bacterial infection. It has been used in clinical settings since the early 1900s — Dakin's solution, used to clean wounds in World War I, was a hypochlorous acid preparation — and modern formulations are FDA-cleared for wound care under brand names like Vashe, Vetericyn, and Hocl. In dermatology specifically, it has been studied for atopic dermatitis (where S. aureus colonization is part of the disease mechanism), inflammatory acne (where C. acnes overgrowth contributes), seborrheic dermatitis, and post-procedure recovery. The selling point versus other antimicrobials is that hypochlorous acid is selective enough to suppress problematic bacteria without wiping out the broader skin microbiome — alcohol, by contrast, kills indiscriminately and disrupts the barrier. Benzoyl peroxide kills C. acnes effectively but irritates and bleaches everything. HOCl is the rare antimicrobial that works without collateral damage, which is why it ended up in the wound clinic in the first place.
In use, the spray is unremarkable in exactly the right way. It mists on cool, absorbs almost instantly, has a very faint clean chlorine note that some people notice and others don't, and produces no sting on application — even on broken or sensitized skin. The instructions are 'spray two to three times on cleansed skin, let air dry, continue with your routine,' and that's all there is to do. It can also be used throughout the day as a mid-routine refresh after a workout, after a mask, after sun exposure, or when an active breakout flares. The effects are subtle and cumulative. Within one to two weeks of consistent twice-daily use, people with sensitive-acne overlap typically notice that breakouts settle faster and that the chronic redness around the cheeks and jawline softens. Rosacea-prone users often notice that flushing episodes are shorter. Eczema sufferers report fewer flare-up episodes, particularly when the spray is used as a daily maintenance step.
The limitations are honest and well-known. The price is the most-cited one — $28 for 120ml of what is essentially saltwater feels expensive, and there is no way around that cost criticism. You can find generic hypochlorous acid sprays from brands like Briotech and SkinSmart at lower per-ml prices, and if you don't care about the Tower 28 packaging or the brand's design language, those alternatives use the same active ingredient. The aluminum aerosol nozzle can also leak slightly if the bottle is jostled in transit. And the effect, taken in isolation, is genuinely subtle — this is a foundational maintenance product, not a transformative single-step treatment. People who come in expecting a dramatic acne or eczema cure tend to be underwhelmed.
What justifies the recommendation is the breadth of use cases combined with the safety profile. There are very few products that can be sprayed on broken skin, used during pregnancy, used on kids, used on body breakouts, used after retinol, used after laser, used over rosacea, and used on sensitive-acne overlap, all without any reasonable concern about adverse effects. The SOS Daily Rescue Facial Spray covers all of those, and the cumulative benefit on inflammation-driven conditions is well-documented in the dermatology literature even if the cosmetic-grade product itself hasn't been the subject of a published clinical trial. It is the product that built Tower 28's reputation, and it is the product that introduced an entire wave of US consumers to a wound-care active they hadn't heard of before. For a sensitive-skin household, it is one of the most useful single bottles you can keep on the shelf.
Formula
Ingredients
The hero actives that drive this product's performance.
| Ingredient | Function | Evidence |
|---|---|---|
| Hypochlorous Acid (0.012%) | The entire formula. Hypochlorous acid is the same antimicrobial molecule produced by the human immune system to fight infection, used here at the cosmetic concentration that targets C. acnes, S. aureus, and other skin-overgrowth bacteria without disrupting the broader skin microbiome. There are essentially no other ingredients — this is hypochlorous acid in saline water, purposely minimalist. | well-established |
Full INCI List · pH 4.5
Electrolyzed Water, Sodium Chloride, Sodium Hypochlorite, Hypochlorous Acid
Product Flags
✓ Fragrance Free✓ Alcohol Free✓ Oil Free✓ Silicone Free✓ Paraben Free✓ Sulfate Free✓ Cruelty Free✓ Vegan✓ Fungal Acne Safe
Compatibility
Skin Match
Best For
sensitive oily combination normal dry
Works For
Not Ideal For
Addresses These Conditions
acne rosacea eczema compromised skin barrier post procedure sensitivity
Routine Step
treatment
Time of Day
AM & PM
Pregnancy Safe
Yes ✓
Layering Tips
Spray onto clean skin and let air dry before the rest of your routine. Can also be misted throughout the day as needed for redness, post-workout flushing, or post-mask irritation.
Results Timeline
Immediate cooling and calming on application. Reduction in active breakout severity, redness, and barrier flushing typically visible within 1-2 weeks of consistent twice-daily use.
Pairs Well With
niacinamide-serumbarrier-creamretinoids-as-pre-steppost-procedure-recovery
Sample AM Routine
- Gentle cleanser
- Tower 28 SOS Daily Rescue Facial Spray
- Serum
- Moisturizer
- SPF
Sample PM Routine
- Cleanser
- Tower 28 SOS Daily Rescue Facial Spray
- Treatment
- Moisturizer
Evidence
Science
The Science
Hypochlorous acid is one of the most extensively studied antimicrobial molecules in clinical use. It is endogenously produced by neutrophils as part of the innate immune response, and FDA-cleared hypochlorous acid wound-care preparations have been used in burn units, chronic wound clinics, and dermatology offices for decades. A 2018 review in Clinical, Cosmetic and Investigational Dermatology surveyed the dermatologic applications of HOCl and noted documented efficacy against C. acnes, S. aureus, and other relevant skin bacteria, with a strong tolerability profile and no documented allergic contact dermatitis from the active itself. A 2017 study in the Journal of Drugs in Dermatology evaluated topical hypochlorous acid spray in atopic dermatitis patients and reported significant reductions in S. aureus colonization and clinical severity scores over 4 weeks of daily use. Separate clinical work has documented HOCl's utility in post-procedure recovery (e.g., after fractional laser, microneedling, and chemical peels) by reducing infection risk and accelerating barrier recovery without irritation. Mechanistically, HOCl works by oxidizing key bacterial cell components — proteins and lipid membranes — at concentrations that are too low to damage human skin cells, which gives it a wide therapeutic window. The Tower 28 spray is a cosmetic-grade product rather than an FDA-cleared medical device, but the active concentration and saline carrier are consistent with the clinical formulations used in dermatology, and the formulation logic is straightforward. No published trial has tested SOS Daily Rescue Facial Spray specifically.
Dermatologist Perspective
Dermatologists have used hypochlorous acid in clinical practice for decades, primarily in wound care and as an adjunct in atopic dermatitis management. Board-certified dermatologists frequently recommend HOCl sprays for patients with eczema, sensitive-acne overlap, post-procedure recovery, and inflammatory rosacea, particularly when stronger antimicrobials like benzoyl peroxide or topical antibiotics are not tolerated. This product is widely cited as the consumer-friendly entry point to the ingredient and is often suggested as a daily maintenance step in pediatric atopic dermatitis routines. Dermatologists typically note that HOCl is most useful as a foundational supportive product rather than a primary treatment for severe disease, and that consistent daily use is more important than any single application.
Guidance
Usage Guide
How to Use
Spray 2-3 times onto cleansed skin, holding the bottle 6-8 inches from the face. Let air dry — do not pat in. Continue with the rest of your skincare routine after the spray has fully absorbed. Can also be used throughout the day as a refresh after workouts, mask use, sun exposure, or breakout flares. Safe for use on broken skin, eczema patches, post-procedure skin, and body breakouts. Pregnancy-safe and gentle enough for children. Replace 12 months after opening per the standard PAO marking.
Value Assessment
At $28 for 120ml, the spray is expensive for the ingredient simplicity. A 75ml travel size is also available, and is the better way to test the product before committing to the full bottle. Generic hypochlorous acid sprays from brands like Briotech and SkinSmart deliver the same active at lower per-ml prices, and if cost is the priority, those are valid alternatives. The Tower 28 premium reflects the brand's positioning, the National Eczema Association heritage, and the role this product played in popularizing the ingredient in mainstream US skincare. For users who want the brand integration with the rest of the SOS line, or who specifically value the formulation discipline, the price is defensible. For users primarily interested in the active itself, alternatives at half the cost exist.
Who Should Buy
Anyone with sensitive, eczema-prone, rosacea-prone, or sensitive-acne overlap skin who wants a foundational antimicrobial maintenance step; people recovering from in-office procedures or barrier damage; pregnant or breastfeeding users seeking safe acne care; parents with kids who have eczema; anyone curious to try cosmetic hypochlorous acid for the first time.
Who Should Skip
Cost-conscious users who would be equally well served by generic hypochlorous acid sprays from Briotech or SkinSmart; people expecting a dramatic single-step transformation rather than cumulative maintenance benefit; anyone who finds the faint chlorine note bothersome; users with severe acne who need prescription therapy as the primary intervention.
Ready to try Tower 28 SOS Daily Rescue Facial Spray?
Details
Details
Texture
Watery mist — sprays as a fine even cloud
Scent
Faint clean chlorine note
Packaging
Aluminum aerosol bottle with fine mist nozzle, 120ml (also available in 75ml travel size)
Finish
non-greasyinvisible
What to Expect on First Use
Cooling, weightless mist that absorbs almost immediately. No tingling, no stinging — even on broken or sensitized skin. Within 1-2 weeks of consistent use, visible reduction in surface inflammation around active breakouts and barrier-related redness.
How Long It Lasts
About 2-3 months with twice-daily use
Period After Opening
12 months
Best Season
All Year
Certifications
VeganCruelty-freeNational Eczema Association acceptedClean at Sephora
Background
The Why
Amy Liu founded Tower 28 partly because she had severe eczema and could not find color cosmetics that didn't trigger flares. Hypochlorous acid had been used in clinical wound care for decades — derm offices already used it on patients, and Liu's own dermatologist had recommended it to her. She built the SOS Daily Rescue Facial Spray as the consumer-friendly version of that clinical product, and it launched in 2020. The spray is widely credited with introducing hypochlorous acid to mainstream US skincare, and the ingredient has since become a recognized name across sensitive-skin dermatology.
About Tower 28 Emerging Brand (2–5 years)
Tower 28 was founded in 2019 by Amy Liu around National Eczema Association acceptance standards. The SOS Daily Rescue Facial Spray is the brand's signature product and the original popularizer of cosmetic hypochlorous acid in the US, which has since become a widely recognized ingredient in sensitive-skin dermatology.
Brand founded: 2019 · Product launched: 2020
Myth vs. Reality
Myths
Myth
Hypochlorous acid is bleach.
Reality
Hypochlorous acid (HOCl) and household bleach (sodium hypochlorite at high concentration) are different molecules with different effects. HOCl is the same molecule the immune system produces to fight infection, and at cosmetic concentrations it is gentle and non-damaging.
Myth
If a product is just water and salt, it can't be doing anything.
Reality
The active here is the hypochlorous acid generated through electrolysis of saline. The minimalism is real, but the active is a clinically validated antimicrobial used in wound care.
Myth
Facial sprays are just expensive water.
Reality
Most are. This one is one of the few exceptions — the formulation contains a documented antimicrobial active, not just thermal water with marketing.
FAQ
FAQ
What does Tower 28 SOS Spray actually do?
It delivers hypochlorous acid — a gentle antimicrobial used in clinical wound care — to the skin. This addresses the bacterial overgrowth involved in acne, eczema flares, post-procedure recovery, and post-workout flushing, without disrupting the broader skin microbiome the way alcohol or benzoyl peroxide does.
Is hypochlorous acid safe?
Yes. Hypochlorous acid is the same molecule your immune system produces to fight infection, and it has been used in FDA-cleared wound care products for decades. At cosmetic concentrations it is gentle, non-irritating, and safe for daily use even on broken skin.
Does it actually work on acne?
Yes, but as a supportive product rather than a primary treatment. It reduces the bacterial component of inflammatory acne and calms the surface inflammation around active breakouts. For severe or cystic acne, it works best alongside a prescription treatment plan.
Can I use this with retinol?
Yes. Spray on clean skin before your retinol — the spray works as a soothing pre-step that reduces the irritation retinoids can cause. It can also be used after retinoid application as a mid-day calming refresh.
Is it safe for kids and pregnancy?
Yes. The formula is essentially saline plus hypochlorous acid, which has no pregnancy-cautious ingredients and is gentle enough for use on children. Many parents use it on kids with eczema or post-bug-bite irritation.
What's the difference between the spray and the rest of the SOS line?
The spray is pure hypochlorous acid in saline — minimalist and used as a baseline antimicrobial layer. The Clear Skin Serum, Clay Mask, and Cleanser build on that hypochlorous acid foundation by adding niacinamide, azelaic acid derivatives, and other actives for more complete daily care.
Community
Community
Common Praise
"Calms breakouts overnight"
"No sting"
"Useful for post-workout flushing"
"Safe for kids"
"Works on body breakouts"
Common Complaints
"Faint chlorine smell"
"Pricey for what's essentially saltwater"
"Spray nozzle can leak"
"Subtle effect on its own"
Notable Endorsements
Sephora bestsellerAllure Best of BeautyNational Eczema Association acceptanceDermatology TikTok favorite
Appears In
best hypochlorous acid spray best facial mist for acne best product for sensitive skin best post procedure spray best tower 28 product
Related Conditions
acne rosacea eczema post procedure sensitivity
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