Employees exposed to hexavalent chromium Cr(VI) are at increased risk of developing serious adverse health effects including lung cancer, asthma and damage to the nasal passages and skin. Employers are required to take measures to protect employees from the hazards associated with exposure to Cr(VI). Hexavalent chromium most commonly exists as a metal (M) chromate (MCrO4), such as lead chromate, or also as chromium trioxide (CrO3).

RJLG offers analysis for hexavalent chromium by OSHA Method ID 215. An air sample is collected using a 37-mm diameter polyvinyl chloride (PVC) filter (5-μm pore size) contained in a polystyrene cassette. Samples from spray paint, chrome plating, or welding require different preparation methods for analysis. 

On February 27, 2006 OSHA issued a final standard for hexavalent chromium. OSHA’s Permissible Exposure Limit (PEL) for hexavlent chromium and for all Cr(VI)  compounds is 5 micrograms of Cr(VI) per cubic meter of air as an 8-hour time- weighted average. The new OSHA regulation requires lower analysis limits and RJLG is equipped to accomodate these requirements.

RJLG offers the OSHA ID-215 method using our Dionex Ion Chromatography (DX500) instrument. OSHA ID-215 has adequate sensitivity for determining Cr(VI) compliance with the proposed OSHA, TWA and AL PELs for Cr(VI) exposure. The method is rapid and easily automated. The extraction and preparation of samples for analysis involve common procedures and equipment.

Media:

To sample for Cr(VI), a 37-mm diameter PVC filter (5-m pore size) is normally used. A calibrated sampling pump is used to draw a representative air sample from the breathing zone of workplace personnel through the cassette and collect particulate on the filter.

Sampling:

Recommended Sampling Rate: 2 liters per minute (L/min). Recommended Air Volume: TWA and AL -960 L (2 L/min for 480 min)

Method:

OSHA ID-215 method

Instrument:

The hexavalent chromium, Cr(VI), is extracted from the PVC filter using a hot aqueous solution containing sodium carbonate (Na2CO3)/ sodium bicarbonate (NaHCO3) and the mixture of phosphate buffer/ magnesium sulfate. After dilution, an aliquot of this solution is analyzed for Cr(VI) by an ion chromatograph equipped with a UV-vis detector at 540-nm following post-column derivatization using diphenyl carbazide.