Which of the following is NOT included in Section 4 of the MSDS, Fire and Explosion Data?

Section 4 of the Material Safety Data Sheet (MSDS), which has been replaced with Safety Data Sheets (SDS), focuses on Fire and Explosion Data. This section provides critical information regarding the flammability and potential hazards posed by the material in the event of a fire or explosion.

Vapour pressure is an important parameter in understanding how readily a substance can form vapours at a given temperature and can relate to its flammability, but it is not specifically categorized as a fire and explosion data point in this section. The other items listed, including auto ignition temperature, flammability range, and flash point, directly pertain to the conditions under which a substance may ignite or contribute to a fire hazard.

Flash point indicates the lowest temperature at which a substance can vaporize to form an ignitable mixture in air, auto ignition temperature signifies the temperature at which a substance ignites without an external ignition source, and the flammability range shows the concentration limits (in air) within which the substance can combust. All these factors directly influence safety measures related to fire and explosion risks.

Thus, vapour pressure is the element that does not specifically fall under the standard fire and explosion data parameters that are critical for immediate fire safety assessments