Wells, Cisterns & Septic Tanks: Hidden Dangers at Home
Many homes have a tank, well or pit that looks harmless, yet the air inside can kill in seconds. Every year people die when they climb in to fix a pump, retrieve a tool or rescue someone. Staying out is the rule.
- Homeowners
- Farms & Rural
- Parents
Where the hidden dangers are
- Wells and well pits. See Well Water.
- Cisterns and rainwater tanks.
- Septic tanks and pump chambers. See Septic System Safety.
- Sump pits, manholes, old cellars, storm drains and dry wells.
- Silos, grain bins and manure pits on farms.
- Unvented crawl spaces and underground vaults. See Attics & Crawlspaces.
Why they are deadly
- Low oxygen: rust, rotting material, or burning fuel uses up oxygen. You can pass out after one or two breaths.
- Toxic gases: hydrogen sulfide (rotten egg smell, but it can block your sense of smell), methane, carbon dioxide and carbon monoxide. See Hydrogen Sulfide.
- Drowning in water or sludge, or being unable to climb out of a smooth, deep space.
- Cave-in of old, unlined walls.
- A person who climbs in to rescue another is often the next victim.
What to do
- Do not enter. Hire a licensed professional with proper gas testing, ventilation, rescue gear and training. See Confined Spaces.
- Keep lids, covers and caps in good condition and locked or secured. Replace rotted or cracked covers.
- Mark the locations and keep children, pets and mowers away. See Childproofing.
- Do not drop tools or lean over the opening. Do not light a match or use a torch near it, since gases may explode.
- Put a sign on old open wells or fill and cap abandoned wells according to local rules.
If someone collapses inside
- Do not go in. Even a few seconds can make you unconscious.
- Call 911 and say it is a confined space rescue.
- If a rope or lifeline is already attached, you may try pulling from outside. Do not climb in.
- Keep others away and wait for rescuers. See Confined Space Rescue.
Standards & references
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