Issue link: http://psai.uberflip.com/i/1426970
5 I PSAI Association Insight, November 10, 2021 (continued on page 6) Combatting the Cold There are two main ways to winterize portable restrooms and equipment: Frost Protection, which includes the steps you can take to prevent equipment freezing in the first place; and Dosing, which involves the use of additives to lower the temperature at which water and waste will freeze. These aren't mutually exclusive strategies and are most effective when used in conjunction, side-by-side. Frost Protection The most obvious step you can take to prevent freezing is to position the toilet away from the cold, ideally indoors. Even a big drafty warehouse or an open barn will offer some protection against the cold. Obviously, that's not always possible, especially on construction sites or civil projects where the portable toilet is often the first structure on site. But if it is possible, operators should always do this first, even if they need to put up a temporary structure such as a wooden shed. In most portable restrooms, the waste tank typically sits hard against the cabin walls. Anything you do to reduce the loss of heat through the walls will help to protect the tank from the cold. It is possible to buy custom- made fabric covers that wrap around restroom cabins to insulate them against the cold. These fit snugly and offer good levels of protection. Alternatively, plywood or foam placed against the sides of the cabin may also provide some protection against frost. While you can't really use this method to insulate the cabin door, that's less of a concern because most cabin doors are double skinned and don't come into direct contact with the tank. In very cold climates, it may also be worth placing insulation beneath the restroom. A sheet of dense PVA foam sandwiched between two layers of ply or a piece of carpet is ideal. Some of the online posts and blogs about winterization mention windchill, which occurs when air at a lower temperature draws heat from any warmer object it meets. People experience the effects of windchill when they lose body heat faster than it's produced. You feel it if you go for a swim outdoors on a cool windy day and then walk back up the beach. Although it can lead to serious harm in people, windchill is not really a major concern with plastic restroom cabins. Shielding the unit from the wind will not in itself prevent freezing. If the outside air temperature is cold enough to freeze the tank, it's cold enough to freeze. That said, placing the toilet in the lee of a building or wall will not do any harm either. In fact, it's often a good idea to find shelter because that will reduce the risk of the unit being blown over by the wind. If you do position restrooms out of the wind, it's important to find a spot that still catches the sun. A frozen tank will thaw more rapidly if the restroom is in the sun than in the shade. If you operate restroom trailers in a region with harsh winters, the best approach is to have the trailers winterized when they're being made. Insulation can be added to the floor, ceiling, and walls; pipework should be wrapped or lagged; and a heater installed. Insulated trailers cost more to build, but it's much easier to make those changes in production than to retrofit them later. An insulated, heated trailer will also be fit for year-round use, giving the operator a much longer window for hire. (continued on page 6) Winterization: How to Prepare Restrooms and Equipment for Extremely Cold Weather (Part 1) (continued from page 4)