Karren Kossey, a partner in Mid Island Safety Consulting, presented "Exposing the Invisible: Asbestos in the Construction Industry" to the Bridging The Gap safety conference in Richmond, B.C. on November 14.
Kossey began by explaining that in 2012 the Hazardous Materials regulations changed. Prior to demolition or renovation, the presence of hazardous materials has to be assessed.
The employer has to ensure that a qualified person inspects the site to identify any asbestos-containing materials or other hazardous materials. Lead, heavy metal and zinc, and even excessive animal feces can be a problem.
Inspection results must also be available at the worksite, including any plans, drawings or specifications.
They must ensure that hazardous materials found are contained and removed appropriately, and all work has to cease if hazardous materials are encountered post survey.
"These surveys are an invasive look at what's in the building," Kossey said.
One common hazard is drug addicts punching holes in walls and storing waste there, which must be dealt with before restoration can resume.
ACM stands for "asbestos-containing material". "Friable" is another term, which means when dry, it is easily crumbled or powdered with hand pressure. That means it can be airborne and is very dangerous.
Asbestos was originally adopted because it has high tensile strength, long fibres, flexibility, is chemical and heat resistant, and is inexpensive.
There are three asbestos related diseases. Asbestosis manifests 10 to 20 years after exposure, lung cancer in 15 to 25 years and mesothelioma in 30 to 45 years, but in some case as few as five years.
Exposures must by very high to get asbestosis, but it's much lower for cancers.
Electricians and plumbers are the hardest hit sector of the industry. They aren't dealing with remediation but they are digging into older buildings.
Asbestos was mined in Quebec until 2013, and Canada was the leading source globally for asbestos until that time, Kossey said.
The exposure limit is 0.1 fibre per cubic centimeter, which is roughly the size of a Canadian quarter. That amount of asbestos contains 2.56 trillion fibres.
It is required to sample any suspect material used before 1990, and if you choose not to test your option is to treat the material as asbestos and remediate regardless.
Asbestos hazards include human hair, which is 600 times larger than asbestos so workers wearing respirators have to be clean shaven. Over 3,000 building products prior to 1990 contained asbestos.
"It's everywhere," Kossey said.
Many workers don't feel it will affect them, because the health effects are not immediate.
Power tools can't be used either, she said, because that makes asbestos friable.
"Lagging" insulation on pipes or other steam and pressure vessels is also a source of asbestos.
Vermiculite was contaminated with asbestos when it was mined from Libby, Mont., and can still be encountered today.
"Water is your best friend with this material," Kossey said. She said a misting system will drop fibres that are invisible to the human eye, but never use a high pressure water system.
There are resources on asbestos in the home on WorkSafeBC's website, as well as informational videos, Kossey said.
The main requirements for asbestos handling are enclosure, controlling fibre release, protecting the worker with personal protective equipment, and decontamination procedures for both workers and tools.
Training is also key, Kossey said.
Before starting a job, you must find out the age of the building, consider structural stability, and ensure a hazmat survey is completed.
Wet environments, lockout and electrical hazards, fall protection, work platforms, confined space entry, emergency response plans and first aid are all considerations.
Heat stress considerations is also vital. "Tyvek (protective suit material) is hot!" Kossey said.