Casella Air Sampling Handbook

The Casella Air Sampling Solutions Handbook is one of the most practical introductory guides available for occupational hygienists, LEV professionals and anyone involved in workplace exposure monitoring. The handbook explains the principles of personal and area air sampling and provides a clear overview of the equipment, sampling heads, filters and pumps commonly used for monitoring airborne contaminants.

The guide covers:

Personal air sampling principles
Dust and fume sampling
Inhalable, thoracic and respirable dust fractions
Sampling pumps and calibration
Sampling heads and cyclones
Vapour and gas monitoring
Sorbent tube sampling
Area and environmental monitoring
Flow-rate selection
Practical occupational hygiene applications

The handbook is designed as a practical reference rather than a regulatory document and provides useful explanations of the equipment and methodologies used during workplace exposure assessments.

This resource is relevant to:

Occupational Hygienists
LEV Consultants
P601 TExT Engineers
Exposure Monitoring Specialists
Health & Safety Professionals
COSHH Assessors
Environmental Monitoring Practitioners
Occupational Health Professionals
Students entering the profession

Source Document

View the Air Sampling Guide here:

View Original Air Sampling Guide

Source: TSI/Casella
Document Type: Technical Handbook
Status: Edition HB4071_03 2022
Last reviewed by LEVCentral: June 2026

LEVCentral Expert Commentary

This handbook has become something of a “starter reference manual” for many occupational hygienists because it explains the practical side of exposure monitoring in a way that is often missing from formal guidance documents.

Whilst standards such as BS EN 689, EH40 and HSG173 explain what should be measured and why, the Casella handbook focuses on how exposure measurements are actually obtained in the workplace. It provides a useful bridge between occupational hygiene theory and field practice.

One of the strongest sections of the handbook is its explanation of particle size fractions. Many practitioners entering the profession initially struggle with the differences between:

Inhalable dust
Thoracic dust
Respirable dust

The handbook explains how different sampling heads are used to selectively collect these fractions and why respirable particles present particular concern because they can penetrate deep into the gas-exchange regions of the lung.

For LEV professionals, the handbook reinforces an important principle:

Effective LEV performance should ultimately be judged by its ability to reduce worker exposure, not simply by achieving airflow targets.

Exposure monitoring and LEV testing are often viewed as separate disciplines. In reality they are complementary. LEV commissioning and TExT activities help verify engineering performance, while air sampling provides evidence of actual worker exposure. Together they provide a far more complete picture of control effectiveness.

The handbook is also particularly useful for explaining sampling trains, calibration requirements and filter-based sampling methodologies. Engineers who regularly encounter occupational hygiene reports often find that understanding the underlying sampling techniques improves their ability to interpret exposure-monitoring data and make informed recommendations.

For new entrants to occupational hygiene, this handbook provides one of the clearest introductions available to the practical equipment and techniques used throughout the profession.

Key Learning Points

Exposure Monitoring Supports Exposure Control

Air sampling provides evidence of worker exposure and helps determine whether control measures are effective.

Different Dust Fractions Require Different Sampling Methods

Inhalable, thoracic and respirable fractions require different sampling heads and flow rates to obtain representative measurements.

Calibration Is Critical

Accurate calibration before and after sampling is essential to ensure reliable exposure measurements.

LEV and Occupational Hygiene Are Closely Linked

Engineering controls and exposure monitoring should be considered complementary components of an effective exposure-control strategy.

Further Resources

Recommended Learning

LEVCentral Observation

One of the reasons this handbook has remained popular for many years is that it explains occupational hygiene instrumentation in plain language.

Many guidance documents focus on regulatory compliance, but this handbook helps practitioners understand the practical realities of collecting meaningful exposure data.

For Occupational Hygienists and for LEV engineers wishing to broaden their understanding of occupational hygiene, it provides an excellent guide to the science and equipment that sit behind workplace exposure assessments.