People searching for a rodent or mouse repellent in Canada find three very different things sold under the same word: scented pouches, sprays and plug-in ultrasonic units. This guide covers the three rodent repellents listed at Pipestone Farm Supply that carry a Health Canada registration (Pest Management Regulatory Agency), and sorts them by what each label actually allows: which animal, indoors or outdoors, and how to use it. Every registration number below can be looked up on Health Canada's Pesticide Label Search, and each product page links to its label.
Three registered repellents, three different jobs
- Rodents Away Odor Free (PCP Reg. No. 33648, Domestic class, registrant Rodents Odor Free International, Inc.) — stearic acid sachets for house mice, indoors.
- Tomcat Rodent Repellent Spray (PCP Reg. No. 32499, Domestic class, registrant Scotts Canada Ltd.) — a denatonium benzoate aerosol for surfaces, outdoors only.
- Tomcat Ultrasonic Rodent Repeller (PCP Reg. No. 33070, Domestic class, registrant Scotts Canada Ltd.) — a plug-in device, indoors only. Health Canada registers it as a device, so it has no chemical guarantee.
None of the three is a rodenticide or a trap, and none of the labels says it kills mice.
Rodents Away Odor Free: stearic acid sachets for house mice indoors
The guarantee on the label reads "Stearic acid and related fatty acids" at 99.7%. The label states its purpose in one sentence: "Rodents Away Odor Free reduces house mouse (Mus musculus) presence and activity." Its use site is "Indoor spaces including modes of transport (e.g., homes and recreational vehicles) where house mice are present." So the registration covers house mice, indoors, including a camper or RV. It does not cover rats and it is not an outdoor product.
From the directions: the sachets "are best located on the floor along walls, in confined places, by gnawed openings, and on either side of doorways", placed "at approximately 3 m (10 ft) intervals throughout the areas", with "one sachet within each space (one per 114 L volume)" for an enclosed space. The label says to "Check every two weeks" and to "Replace sachets as necessary." Precautions include "KEEP OUT OF REACH OF CHILDREN" and "Wash thoroughly with soap and water after handling."
We list the Rodents Away Odor Free 6-pack of 40 g sachets; the brand page is Rodents Away Odor Free.
Tomcat Rodent Repellent Spray: a bitter coating for outdoor surfaces
The guarantee is denatonium benzoate 0.075%, a bitter-tasting compound. The label reads: "This product is used to control damage caused by mice, rats and voles." Where it may be used: "Spray on fence posts, bark of trees, siding, garbage, and places reached by rodents." The label is explicit that it is "For outdoor use only."
From the directions: "Generously apply to dry surfaces." "Spray all surfaces to be protected until completely wet." "Allow to dry before handling or re-applying." "Annual re-application is advised." The restrictions matter on a farm or acreage: "Never use on food, edible plants or directly on the fruit or nuts of trees." and "Do not use on sugar maple trees if sap is to be used since the product could affect the taste of the maple syrup." The label also says to "Wear chemical resistant gloves when handling product or contaminated equipment."
See Tomcat Rodent Repellent Spray 400 g.
Tomcat Ultrasonic Rodent Repeller: a plug-in unit for one indoor area
The label describes a device that "Repels mice and rats from areas where ultrasonic soundwaves are present." It plugs into "a 120V AC outlet" and is rated "Covers areas up to 46 m2". Placement, from the label: "Best placement is 0.5 to 1 m off the floor with the speaker grill aimed at known problem areas." and "Do not block speaker with drapes, furniture or other obstructions."
Two label lines set expectations: "Ultrasound is directional and can't penetrate anything solid." and "Do not expect immediate results." The label's own answer on coverage: "One Tomcat® Ultrasonic Rodent Repeller is capable of covering 46 m2. Most homes will require multiple units." The box lists it as ideal for "Homes and Apartments", "Farm Buildings, Boats and RVs" and "Domestic Kennels and Stables". On pets, the label says it is "Safe to use around non-rodent pets", and "Do not keep rodent pets, gerbils, rabbits, hamsters or guinea pigs in an ultrasonically protected area." Precautions include "Do not use outdoors." and "Do not expose to moisture."
See Tomcat Ultrasonic Rodent Repeller.
Which one fits where, by label
- Inside the house, a cabin or an RV: Rodents Away's label names house mice and "recreational vehicles"; the ultrasonic unit's box names homes, farm buildings, boats and RVs, for mice and rats, one 46 m2 area per unit.
- Outdoors, on fence posts, tree bark, siding or garbage: only the Tomcat spray; neither of the other two labels allows outdoor use.
- Rats: the spray (outdoors) and the ultrasonic unit (indoors) name rats. Rodents Away does not.
- A garage, shop or farm building: indoors, so the spray is out. The ultrasonic label rules out moisture and says ultrasound "can't penetrate anything solid", so place it with a clear line to the problem area; Rodents Away's label covers indoor spaces where house mice are present.
When a repellent is not the whole answer
None of these labels claims to remove mice that are already living in a building. For that, the options are registered baits in bait stations, and traps. For setting and checking traps, see Mouse and Rat Traps in Canada: Snap, Wood, Glue or Live-Catch?. Our guide to mouse and rat bait in Canada by class and label sorts the baits we list by active ingredient and marketing class, and Tomcat bait stations: mouse vs rat, refillable vs disposable compares the Tomcat stations, for example the Tomcat refillable mouse bait station with 8 blocks. If you would rather not use bait, we also list Tomcat mouse snap traps and the Tomcat multiple live catch mouse trap. For barns and outbuildings before winter, see Fall mouse control for barns, shops and outbuildings in Alberta. Our rat and mouse control category lists the stations and traps.
Common questions
Is stearic acid a mouse repellent? In Canada, stearic acid and related fatty acids are the registered active ingredient in Rodents Away Odor Free (PCP Reg. No. 33648), at 99.7%. Its label covers house mice in indoor spaces.
Can I use a mouse repellent in an RV or camper? The Rodents Away label names "recreational vehicles" as an example of its indoor use site. The Tomcat ultrasonic unit's box lists "Farm Buildings, Boats and RVs"; it plugs into a 120V AC outlet and must be kept away from moisture. For storage season, see How to Keep Mice Out of an RV, Camper or Trailer Over Winter: What the Labels Allow.
Can I spray a repellent inside the house? Not the Tomcat Rodent Repellent Spray; its label says "For outdoor use only."
How can I tell whether a repellent is registered? A registered pest control product carries a PCP registration number on its label, and you can look any number up on Health Canada's Pesticide Label Search. The three repellents in this guide each have one.
Pipestone Farm Supply is in Millet, Alberta, between Leduc and Wetaskiwin, south of Edmonton, with in-store pickup and Canada-wide shipping.
Pesticides are regulated by Health Canada; read and follow the label before every use.
Sources: Health Canada Pesticide Label Search, registrations 33648 (Rodents Away Odor Free), 32499 (Tomcat Rodent Repellent Spray) and 33070 (Tomcat Ultrasonic Rodent Repeller), all Domestic class, viewed September 2026; every quotation above was checked against those label files.