Predicting PID readings:

Meter readings scenario: Your team is reading a known spill of xylene. Entry reports readings of 19,782 PPM on PID. Using the CF for xylene of 0.46 the actual concentration in air is 9,100 PPM.

You are the science officer on this incident: You know that xylene has a vapor pressure of 7 mmHg. To predict, you multiplied the vapor pressure (7 mmHg) x 1300 to determine the maximum airborne concentration of 9,100 PPM. 9,100 divided by the C.F. of 0.46 tells you the anticipated value to be reported by the entry teams meter which is 19,782 PPM.

Summary to predict PID: 1300 x vapor pressure = ______PPM ÷ C.F. = predicted meter reading

The author recognizes that PID operate in limited span. The values shown here are used to demonstrate the math.

Values are approximations not intended for response.