China
Africa
Explore chapters and articles related to this topic
Construction Issues
Published in Martin B., S.Z., of Industrial Hygiene, 2018
A fundamental provision of AHERA’s coverage was the establishment of a process mandating inspections and re-inspections of the primary and secondary schools. The purpose of the inspections is to assess the location, condition, and exposure potential of asbestos-containing building materials (ACBM) based upon the ACBM’s friability. According to AHERA, a material is considered friable if it is capable of being reduced to powder or dust with hand or mechanical pressure. AHERA categorized ACBM in seven hazard assessment categories, based on potential to create exposure events. The AHERA Standard recognized that certain asbestos types had greater potential to create exposure episodes based on the given materials ability to release fibers that can become airborne. This fiber release capability is related to the material’s friability. Table 15.8 depicts the AHERA assessment categories. The type of ACBM will dictate the minimum number of samples that will have to be collected to verify whether a homogeneous sampling area can be called non-ACM.
Current Uses of Asbestos
Published in Kenneth F. Cherry, Asbestos, 2020
The potential of an asbestos-containing product for releasing breathable fibers depends on its degree of friability. “Friable” means that the material can be crumbled with hand pressure and is therefore likely to emit fibers. The fibrous, fluffy sprayed-on materials used for fireproofing, insulation, or soundproofing are considered to be friable and they readily release airborne fibers if disturbed. Materials such as vinyl-asbestos floor tile or roofing felts are considered nonfriable and generally do not emit airborne fibers unless subjected to sanding or sawing operations. Asbestoscement pipe or sheet can emit airborne fibers if the materials are cut or sawed or if they are broken during demolition operations.
Material Characterization and Analysis
Published in Muhammad E. Fayed, Thomas S. Skocir, Mechanical Conveyors, 2018
Muhammad E. Fayed, Thomas S. Skocir
Some materials are degradable or friable; that is, their particles or lumps break down mechanically through impact, agitation, or attrition. The resulting materials will have a different size consistency; this may affect the behavior of the material. Many foods fall into this category.
Releasability of asbestos fibers from weathered roof cement
Published in Journal of Occupational and Environmental Hygiene, 2018
Andrew F. Oberta, Lee Poye, Steven P. Compton
Two of the panels were sampled according to ASTM D5755.[9] The “microvacuum” sampling procedure consists of vacuuming the surface with a flexible plastic inlet tube attached to a 25-mm air-sampling cassette through which air is drawn at 2 L min−1. On the first microvacuum sample, 25216-C-01 from the center panel, it was observed that the surface layer, which had weathered from black to dark brown, was crumbling (becoming friable) and a light brown sub-layer was being exposed. A friable material is one that “can be crumbled, pulverized, or reduced to powder by hand pressure.” [10] In this case, the hand pressure was applied with the inlet tube attached to the sampling cassette.