Which ERG guide number would you consult for guidance on a highway spill of liquified sulfur dioxide?

• A. #16
• B. #32
• C. #4
• D. #8

Answer: (A)

When a highway spill involves liquified sulfur dioxide, the main concern is its toxicity if inhaled. That makes the guide for toxic inhalation hazard (TIH) gases the most relevant ERG section. This guide is designed specifically for TIH gases and provides the immediate actions responders should take, such as isolating the area, evacuating as needed, and approaching from the upwind side, along with guidance on protective actions and appropriate PPE. It also helps responders understand potential health effects and release scenarios to determine safe distances and containment steps.

Other ERG guides cover different hazard classes (for example, corrosives, flammable liquids, or oxidizers). Those would not address the inhalation hazard profile of sulfur dioxide as effectively, so the TIH gases guide is the best fit for this scenario.