concentration: Calculate new concentration after a time interval

In dwnadler/rEHS: A set of tools for EHS management

Description

When using dilution ventilation, the flow rate of fresh air is determined by (a) contaminant generation, (b) proper mixing, and (c) target final concentration. The methods used apply to uniform rates of generation and low to moderate toxicity. This function is used to determine the concentration buildup that will occur over a given period measured in minutes.

Usage

concentration(contaminant.generation.rate, flow.rate.cfm, timeframe, volume.cf)

Arguments

contaminant.generation.rate	the rate of contaminant released in cubic feet per minute (cfm)
flow.rate.cfm	the rate of air flow in cubic feet per minute (cfm)
timeframe	the number of minutes (min) it takes to reach the new concentration
volume.cf	the volume of the room in cubic feet (cf)

Examples

## concentration(1.4, 2500, 11, 75000)
## contaminant generation is 1.4 cfm
## air flow is 2500 cfm
## 11 minutes is the time interval
## room is 75,000 cubic feet
## "Concentration: 171.90 ppm"

  

dwnadler/rEHS documentation built on Dec. 20, 2021, 2:16 a.m.