Air sampling accessories
Personal sampler accessories
Product range: Workplace Monitors for Dusts and Gases
Overview
Air Sampling Heads
Total Inhalable
Inhalable sample heads collect a particle size of 100 micron and smaller; i.e. all available inhalable dust. All the sampling heads are designed for use with a controlled rate of air provided via a personal air sampling pump. Sampling media (filters) are placed inside the heads directly or using cassettes. The filter will be weighed before sampling and then again afterwards to gravimetrically determine the amount of dust collected.
Respirable Fraction
Respirable fraction sampling heads are specifically designed to separate out the smaller dust fractions which travel further into the human airways and are generally more harmful. The collection efficiency curve meets the ACGIH/ISO/CEN standards for a respirable curve with a median 50% cut point of 4micron. The cyclones work by physical separation of particles and the flow of air through the cyclone must be controlled accurately by the personal sampling pump for the cyclones to work efficiently.
Other Sampling Heads
We also supply other sampling heads designed for specific applications, for example; a Swinnex head for Rosin/Welding fumes or a filter head for lead sampling.
Asbestos sampling
Asbestos is a group of naturally occurring fibrous silicate minerals which have been used widely in construction and industry because of its flexibility, strength, chemical resistance, insulation properties and non-combustibility. Asbestos releases fibres into the air if it becomes damaged or disturbed and asbestos fibre inhalation is associated with lung diseases, i.e., asbestosis, mesothelioma and lung cancer.
Airborne asbestos fibres are sampled by drawing a measured volume of air through a membrane filter. This is then mounted onto a microscope slide and rendered transparent with solvents, generally acetone/glycerol triacetate. Fibres on a measured area of filter are counted using phase contrast microscopy (PCM) and the number concentration of fibres in the air is calculated. Casella offers specific sampling accessories for the analysis of asbestos fibres; An open faced filter holder fitted with an electrically conducting cylindrical cowl is required along with MCE filters with a printed grid. MCE filters (a mixture of cellulose acetate and cellulose nitrate) are recommended for asbestos sampling as they are readily rendered transparent for fibre counting. Pre-loaded asbestos cassettes are also available in pore sizes of 0.8µm and 0.45µm for ease of use.
Sorbent Tubes
These are sealed glass tubes, with generally 2 sections of adsorbent material. They are used for monitoring levels of organic vapours and gases. Both ends of the tube are broken off and air is drawn through the sampling tube and the vapour or gas that’s being monitored is adsorbed onto the material in the tube. After sampling, the ends of the tube are capped and sent to a laboratory where the material is desorbed from the tube, either chemically or thermally, and analysed usually by a gas chromatograph.
Different types of adsorbent material are used; the most common being charcoal and silica gel. Please refer to your MDHS, NIOSH, OSHA or other standard method to find out which type of tube your need.
