Name two common types of occupational air sampling media and the hazards they measure.

• A. Gravimetric filters for inhalable/respirable particulates; sorbent tubes or DNPH cartridges for VOCs or aldehydes (e.g., formaldehyde).
• B. Sorbent tubes for metals; DNPH for humidity.
• C. Gravimetric filters for gases; DNPH for humidity.
• D. Water samples for aerosols; tapes for DNA.

Answer: (A)

In occupational air monitoring, two common sampling media cover the main hazard types you’re likely to encounter: particulates and gases/vapors. Gravimetric filters are used to quantify dust by collecting airborne particles on a filter, then weighing the filter before and after sampling to determine the mass of inhalable or respirable particulates. This directly gives the dust concentration in the air and helps assess particulate exposure.

For gases and vapors, sorbent-based media such as sorbent tubes or DNPH cartridges are used. Sorbent tubes trap volatile organic compounds by adsorption onto the sorbent material, allowing analysis of VOCs in the air. DNPH cartridges react with carbonyl compounds (like aldehydes, including formaldehyde) to form hydrazones, which can be measured with spectrophotometry or HPLC. This combination is well-suited for capturing and quantifying gases and vapors that aren’t effectively measured by a gravimetric filter.

So, gravimetric filters quantify particulates (inhalable/respirable dust), while sorbent tubes and DNPH cartridges quantify VOCs and aldehydes, respectively.