Recently, a poisoning and suffocation accident occurred at a pig farm in Anshun, Guizhou, resulting in the tragic deaths of three people. Such tragedies are not uncommon in scenarios involving confined space operations such as septic tanks and sewage pools. Accidents often begin with one person in danger, followed by colleagues blindly entering to rescue without adequate protective awareness, ultimately leading to an increase in casualties. This once again sounds a safety alarm for EHS managers across all industries.
In enclosed or partially enclosed spaces such as farms, chemical plants, and municipal sewer systems, hydrogen sulfide, ammonia, methane, and other hazardous gases may accumulate, often together with oxygen deficiency. Entering without atmospheric testing - or relying on odor as a warning - is a major cause of poisoning and asphyxiation incidents.
The first rule is to ventilate, test the atmosphere, and only then enter under a controlled confined-space procedure. Multi-gas monitoring should continue before and during entry. If hazardous concentrations cannot be reduced below acceptable limits or oxygen is deficient, workers need appropriate atmosphere-supplying respiratory protection.
Air-purifying respirators are not suitable for oxygen-deficient atmospheres or where contaminant concentrations are unknown. These conditions require positive-pressure self-contained breathing apparatus (SCBA) or a supplied-air respirator meeting the applicable requirements, with an independent breathing-air supply.
Emergency rescue planning is equally important. Where non-entry rescue is feasible, full-body harnesses, lifelines, and a rescue tripod or winch should be available. Attendants should never enter an unsafe atmosphere without the same level of appropriate respiratory protection and rescue controls.
Confined-space safety requires a complete program: entry permits, atmospheric testing, ventilation, communication, suitable PPE, rescue planning, and regular drills. These controls need to work together to prevent a single exposure from becoming a multiple-casualty event.
News source:Safety Management Network, 2026-05-29: "Poisoning and Suffocation Accident at a Pig Farm in Anshun, Guizhou, Resulting in 3 Deaths." This article only provides PPE knowledge interpretation based on public news topics.
