Managing asbestos removal for trouble-free projects
Getting asbestos removal right is crucial to avoiding project delays and reputational harm.
The presence of asbestos on building projects has the potential to cause serious problems if not managed correctly.
The challenge
Inappropriate management can lead to projects being temporarily shut down, have significant cost implications, and damage the reputation of the firms involved, particularly if there is contamination outside the work zone. Following a tested and well-implemented process helps ensure projects come in on time and on budget while removing the potential for harm to workers and the wider community.
As part of Ngā iti Kahurangi (NIK) school’s refurbishment programme an asbestos management survey was conducted for Norsewood and Districts School in Manawatu-Wanganui. The survey revealed asbestos in its main classroom block where work was to be carried out. The presence of asbestos meant the refurbishment project couldn’t proceed until the asbestos was either removed or isolated.
Torque IP Project Manager Mark Carter says that this was a Class A asbestos removal project, meaning the asbestos containing material had a high potential for causing harm during the refurbishment work through becoming airborne.
The Class A asbestos removal required that the entire working space be enclosed and negative pressure units (NPU) used to maintain the correct negative pressure inside the space. NPUs are equipped with HEPA filters that are 99.9% effective in filtering the air.
The solution
As project manager Torque IP selected the asbestos removal contractor and ran the project through to completion. This included communications with the school, the contractor, the Ministry and an independent asbestos assessor.
The Ministry requires asbestos removal to be conducted outside of school hours if possible. The affected building contained the majority of the school’s classrooms, so the project had to be tightly managed over the summer break to allow the school to open on time in the new year. Torque IP selected McMahon Services as the asbestos removal contractor following a Ministry of Education aligned RFQ process. The job required the removal of the suspended ceiling in the block, and the clearing of the ceiling cavity and other areas in the block of asbestos.
The entire working space had to be enclosed with negative pressure units (NPU) used to maintain the correct negative pressure inside the fully enclosed space. Additionally mobile units were deployed to ensure there were no ‘dead spots’. Air inlets were used to ensure sufficient airflow, with 40000cm3 of air being circulated every eight minutes. In addition a rigorous procedure is required to transition the removed material out of the building to a temporary safe storage location for disposal at the end of the project.
Mark Carter says that the need for absolute certainty around the work being done means that neither Torque IP as project manager nor the asbestos removal contractor can inspect and approve their own work. Instead an independent assessor is on site for the duration of the project, both to ensure that correct removal processes were adhered to and to complete sample air testing. A final multi-stage inspection was also completed consisting of visual inspection, sample surface testing and air-quality testing.
Only when the independent assessor had provided a Clearance Certificate was the asbestos removal considered complete. With the asbestos safely removed, work could commence on the Ngā iti Kahurangi programme work for the school.
Only when an independent assessor had provided a “Clearance Certificate” was the asbestos removal considered complete and the NIK work programme for the school could commence.
The result
Despite the tight schedule the project was completed on time. Norsewood and Districts School Principal Angela McQuarrie says the project could not have gone better. “We knew it would be a complex job that had to be done within a very tight timeframe, so we had a contingency plan if it wasn’t completed on time, which involved using another hall and two classrooms at another school. But they were really right on the nail, having the classrooms ready for us when they said they would. They were in and out in six weeks. I was impressed.”