Laboratory Test: Screening Test for Polymer Off‑Gassing (TVOC‑PID)

This article describes one of three analytical procedures used in kinetic studies of polymer off‑gassing. A general overview of the full testing program is provided separately, along with links to the other available methods.

LCS Laboratory conducts this screening test to evaluate the emission rate of Total Volatile Organic Compounds (TVOC) from polymeric materials under controlled conditions.

Purpose of the TVOC‑PID Screening Test

The test measures the kinetics of VOC release from a sample maintained at constant temperature. It provides time‑resolved data showing how the concentration of volatile compounds changes during the test period.

Test Procedure

The sample is placed in a stainless‑steel or glass vessel.
The vessel is purged with solvent‑free air at a constant flow rate.
VOC concentration in the outlet air is monitored using an in‑line Photoionization Detector (PID).

Available test durations include 6‑hour, 30‑hour, and 55‑hour runs. Testing may be performed at ambient or elevated temperatures. Relative humidity of the purge air can be controlled from 0% RH to ambient levels, and up to 80% RH. Samples may be tested in their commercial form or as dust.

Data and Reporting

Results are presented as:

VOC concentration in the headspace over time, and
Emission rate, expressed as milligrams of VOC released per kilogram of sample per hour (mg/kg/hr).

This format allows assessment of both instantaneous concentration and overall emission behavior.

Advantages and Limitations

Advantages: Rapid and cost‑efficient screening, Sensitivity of approximately 0.05 mg/hr

Limitations: Results are semi‑quantitative, PID detectors do not respond to certain compounds, including: Light alcohols, Formaldehyde, Low‑molecular‑weight hydrocarbons (e.g., methane through butane)

Other off‑gassing procedures for polymers are described on the summary page, including methods suitable for compound‑specific analysis and quantitative VOC profiling.