Microscopy

Asbestos is a generic name applied to a group of naturally occurring minerals that have been used in commercial products. Asbestos testing falls within Bureau Veritas’ microscopy scope of services, as it is best identified under a microscope.

With laboratories in Canada and the United States, Bureau Veritas is uniquely positioned within the building science and industrial hygiene markets. When analyzing for asbestos, we use Phase Contract Microscopy (PCM), Polarized Light Microscopy (PLM), and Transmission Electron Microscopy (TEM).

BUREAU VERITAS TAKES PRIDE IN PROVIDING UNIQUE SOLUTIONS TO CHALLENGING PROBLEMS THROUGH MATERIALS CHARACTERIZATION

Materials Characterization is a branch of materials science that incorporates elements of physics, chemistry, engineering, and other disciplines to examine the structure and properties of materials, from the atomic level up to the coarse grain structural level. Our electron microscopes allow us to determine the structure of a sample down to its elemental composition and detect stress or internal fractures. We can determine sample composition, fiber and particle size, material origin, foreign substances, physical defects, and various other properties.

We are experts at analyzing a wide range of samples, including:

• Fibers and particulate
• Stack emissions
• Metals and alloys
• Textiles
• Water and sludge
• Residues
• Corroded surfaces
• Building materials
• Cast Metals and ceramics
• Composites and polymers
• Product failure samples
• Nanoparticles

We thrive on providing the industry’s best solutions to your challenges. 

WHY CONDUCT NANOMATERIALS ANALYSIS?

Nanotechnology is a growing field that is still in its infancy and the potential occupational health and safety consequences are not yet known. Our laboratory is one of the contracted laboratories that collaborates with government, industry and universities, making us one of the front runners of sizing and characterizing particles at the nanoscale.

At Bureau Veritas, we can assist with analyzing surrounding work practices, controls and employee protection equipment needs, as well as, exposure assessments for carbon nanotube materials.

Job tasks and processes can be characterized where employees work with raw or processed carbon nanotube (CNT) containing materials by taking air and wipe samples.

Engineering controls can be implemented to reduce exposures for specific tasks.

Airborne levels can be assessed by NIOSH Method 5040 and compared to the NIOSH REL (recommended exposure limit) of 1 micrograms/m3, 8-hour TWA.

Further examination of air samples by transmission electron microscopy (TEM) with X-ray energy dispersive spectroscopy (EDS) can be performed to quantify CNT, obtain size data and rule out elemental carbon containing particles such as carbon black and diesel soot. Wipe sample analysis using electron microscopy evaluates the effectiveness of work practices, housekeeping procedures and engineering controls.

BUREAU VERITAS IS A LEADER IN DEVELOPING MICROSCOPY-BASED METHODS

Utilizing the most advanced techniques, our team of certified industrial hygienists (CIH), chemists (Ph.D., MS, and BS levels), and microscopists provides method development and validation services for asbestos, nanomaterials, and carbon nanotubes.

WHAT’S THE DIFFERENCE BETWEEN CARBON BLACK AND SOOT?

Carbon black is manufactured under controlled conditions for commercial use, primarily in the rubber, painting, and printing industries. Greater than 97% of carbon black consists of elemental carbon arranged as aciniform particulate.

Aciniform morphology (grape-like clusters of carbon black) can be visualized by polarized light microscopy (PLM) for visual estimation. However, confirmation of the carbon black is required at much higher magnifications using transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). Individual particles of carbon black have smooth edges at high magnifications whereas soot has serrated or irregular edges.

Additionally, the types of organic compounds (including PAHs) are not extractable in biological fluids and are not as biologically potent as those present in soot. Confirming the elemental composition of carbon black (typically carbon and minor sulfur) by energy dispersive spectroscopy (EDS) supports the morphological identification of the aciniform particles).

Soot is the unwanted by-product of combustion of carbon-based materials for the generation of energy or heat, or for waste disposal. Depending upon the type of soot, the relative amount and type of carbon and particulate characteristics can vary considerably. Less than 60% of the total soot particulate mass is carbon. Soot has much greater percentages of ash and solvent-extractable organic compounds.

Whether you are dealing with carbon black or soot, Bureau Veritas can meet your analytical needs.

(Source:  Watson, A. Y., & Valberg, P. A. (2001). Carbon black and soot: two different substances. AIHAJ-American Industrial Hygiene Association, 62(2), 218-228