Last week, while cleaning some of my Stanfield heat pads, I found myself appreciating their many fine qualities. A prime feature is the versatile range of sizes available. The large surface of the pads provides floor heat over a considerable area. You ask "Why use floor pads, I keep my tortoises quarters plenty warm." I have found that a floor in a well-heated room can remain prohibitively chilly in cold weather. A tortoise sitting on a cold floor in a warm room can still become chilled, which may lead to respiratory, digestive and other problems.
Stanfield heat pads were originally produced and sold to the agriculture industry to provide a warm resting area for small farm animals, mainly piglets. Nowadays the list of applications has grown to include tortoises, boid snakes, iguanas and monitors, and ostriches etc.
These heat pads consist of rigid fiberglass material incorporating a heating element. Their heavy construction, flat profile and reliability make them an astute addition to the exotic tortoise quarters. The installation, use and maintenance of the pads is not however, without serious consideration. If you are building a new tortoise quarters, build it so that the pads stay dry. Make sure that the heating pads are well drained by sloping the floor towards the door or a drain, thus preventing liquids from remaining on or under them. If you are installing pads in an existing facility, build a sub floor and make it slope. If I have choice, I prefer plywood as a pad substrate because it does not conduct heat away from the pads like concrete does, thus allowing me to use a lower control setting and save energy. The pads are factory drilled, so use these holes to anchor them securely. To protect the power cord from fretful tortoises, run it through schedule 40 P.V.C. pipe which is anchored firmly by steel plumbing strap.
When the pads are in use they must be appropriately regulated. First and foremost, use only power sources that are protected by ground fault interrupter (GFI) circuits. I use the manufacturer's pad controller (F920) for all my outdoor tortoise housing. This control unit will govern up to 2,000 watts worth of pads, and automatically cycles electricity to the pads based on information received from a remote sensor-probe. This is no time to skimp on your setup. The F920 is well worth the money, I have many in operation and they work well. A rheostat (dimmer) is OK to use also, but only if the background temperature is controlled.
On all of my controlled environment applications, i.e. in indoor set-ups, I use rheostats such as the Osborne's F911, that are continuously monitored with voltmeters. If I have a number of pads in like-kind enclosures that require heat settings, I use a remote probe thermosensor and set the temperature where I want it. Then I read the voltmeter and set the other pads accordingly. Otherwise, rheostats are much too user dependent and can lead to too low or dangerously too high pad temperatures (as can using any type of bedding material over the pads). The pads still have to be adjusted as the background air temperature changes. If you are skimping and using a rheostat in an uncontrolled environment, an uncompensated for rise in air temperature such as a suddenly warm day can be a recipe for debacle.
What happens when a pad becomes too hot? One obvious possibility is injury to your animals. Another possibility is that the heating element inside the pad could become overly hot for a prolonged period of time and accelerate the aging of the element, causing premature loss of pad function. When this happens the fiberglass immediately surrounding the short may oxidize and allow moisture to enter. The stage is then set for perhaps a life threatening electrical shock to the user who handles or hoses the pads off without first unplugging them. Now you have a darn good reason for not using tinder (I mean bedding) on your pads. Fire!
Moisture in and of itself can ruin a heat pad. If constantly present, moisture can wick into the pad and cause an electrical short or malfunction. I prefer to dry sweep my pads when possible, and I always treat the pads as potentially dangerous appliances. So, give the pads the respect and consideration they deserve and check them often for possible loss of function.
Photo by Sean Baker.
Originally published in the Tortuga Gazette 30(3): 6, March 1994
