What percent of H2S becomes dangerous within 30 minutes?

When assessing the dangers of hydrogen sulfide (H2S), it is important to understand its concentrations and the corresponding health risks. At concentrations between 0.005 and 0.07 percent, H2S can cause significant health effects within a short exposure time, such as 30 minutes. This concentration range is particularly concerning because it can lead to symptoms like irritation of the eyes, respiratory distress, or even loss of consciousness for higher exposures.

Recognizing the properties and effects of H2S is critical for safety in environments where it might be present. The option selected accurately reflects the threshold where H2S starts to present serious risks, highlighting the necessity for monitoring and appropriate safety measures in any operation where H2S exposure is possible.

The other ranges do not accurately capture the threshold at which substantial health risks begin to manifest within a 30-minute exposure period, making them less relevant in the context of immediate safety concerns.