In a recent safety investigation, asbestos fibers were discovered in concrete spacer blocks used in a concrete bridge deck, prompting a critical alert for construction professionals. These spacer blocks, historically made from concrete and more recently from plastic, were found to contain white asbestos fibers, a discovery made during a routine analysis.
Asbestos, a hazardous material, has been subject to bans for its various types over the years. Blue (crocidolite) and brown (amosite) asbestos were outlawed in 1985, with white (Chrysotile) asbestos following in 1999, under The Asbestos (Prohibitions) (Amendment) Regulations. While amosite and crocidolite are the most dangerous, all asbestos types pose health risks.
The focus of this alert is on hard concrete spacer blocks used prior to 1999, which may contain up to 5% white asbestos fibers, classifying them as asbestos cement products. Unfortunately, structure records rarely detail the manufacturer, type, and location of these spacers, making their detection challenging.
Given the potential presence of asbestos fibers in any concrete removal activities involving structures built before 1999, such works are designated as non-licensed by the Health and Safety Executive (HSE). This classification underscores the importance of assuming the presence of asbestos in such cases.
The HSE advises that the health risks from asbestos cement spacer blocks are low. Activities like inspection, maintenance, and concrete repairs are not classified as asbestos work. However, standard practices like dust suppression and pre-wetting surfaces during mechanical concrete removal are recommended to minimize risks.
Demolished concrete waste, potentially containing these spacers, can be crushed and recycled, provided it is kept damp. If asbestos cement spacers are discovered, they should be marked with paint. Workers involved in disturbing reinforced concrete should adhere to relevant guidance regarding personal protective equipment (PPE).