With the advent of indoor plumbing, clogged drain lines have become very much a part of our lives. When it is time to unclog a sink drain line, start with the least aggressive method and work your way up.

Step 1: Try a good old fashion plunger. Choose the little plunger with a short handle, made specifically for sink drain lines. Seat the plunger over the drain opening and press down with some force. Allow the cup to reform itself and press again. After three or four plunges, if possible, run a little hot water through the drain. Repeat the process several times until the line is clear. If this does not work, move on to step two.

Step 2: Check the plumbing. Clear everything out from under the sink and place a bucket beneath the drain trap. Loosen the two lock nuts holding the curved portion of the trap in place and remove the trap. Be prepared for water to rush out of the line. Check the trap for any clogs and (wearing rubber gloves) manually clear the drain line of any debris.

Step 3: Replace the trap, hand tighten the nuts and test the line again.

Step 4: If the drain is still clogged, a chemical drain cleaner may be the next step. Straight sulfuric acid or sodium hydroxide granules are the best products for this purpose. Keep in mind that chemical drain cleaners remain in the line for an extended period. Never use more than one type of drain cleaner in the same drain within a three-month period. Read all directions carefully and follow them completely to avoid damage to the pipes — or worse. Since you cannot mix drain cleaners, choosing the strongest chemical the first time is the right decision. Keep in mind that using a chemical drain cleaner will cause difficulty for you or the plumber if augering the line becomes necessary. If the line is completely clogged, skip the chemicals and move onto the drain auger instead.

Step 5: There are several different types of drain augers. Check with your local hardware store or rental yard to identify the best tool for the job. Wear protective goggles and leather gloves when operating an auger. Remove the drain trap and feed the cable directly into the drain line. For best results, work slowly and let the cable do the job for you.