For further details about Rhodar's new range of Mould Remediation Services, please email Andrew Cottrell.
Case Study: National Library of Scotland
Origins:
After a significant flood where poor workmanship caused a joint in a recently installed pipe to fail, one of the Strong Rooms on the “stack floor” became contaminated with mould infestation. Toxic Mould had infested the linoleum and firewall that made up the wall of the strong room adjacent to the smoke ducting. All of the book and document collection had since been removed from the area and a survey had been conducted.
After the lab testing Rhodar were asked as experts in toxic mould removal to establish a ‘plan of work’ to remove the significant mould accumulation and reinstate the area back to dry shell. After establishing the ‘plan of works’ acceptable to the client, Rhodar were contracted to remove the mould to ensure that the area could be re-occupied.
The risk to the client of the mould was two fold; it presented an obvious health risk which was only getting greater; and also presented a risk of physical destruction to the valuable books and the fabric of the building.
The Works:
The Team made up of Rhodar’s Specialist Mould Technical Operatives & Supervisors (from Rhodar Leeds and Glasgow offices) were sent to the library to remediate the area. Working alongside the existing collection on the exterior of the strong room corridor, where some of the books were over two hundred years old, the team commenced remediation by constructing a fire retardant polythene enclosure to encompass the areas of contaminated flooring, walls and ducting. Shelving was removed and stored before cleaning and re-instatement. The smoke fans within the duct provided adequate negative pressure to suppress spores.
Operatives were required to wear specialist respiratory protective equipment providing organic and dust protection to an APF of 40.
Using the shadow vacuuming technique and the application of a specialised Jati Mould remover, the contaminated ducting insulation was removed and pipe work cleaned to visual standard. Once this was completed, the contaminated flooring was removed and the remaining floor was again treated with Jati mould remover. As the specialised Mould Remover was applied, the floor was seen to react to the application indicating that on the floor a species of toxic mould remained. The floor was allowed to dry then scraped and vacuumed using H-Type vacuums (HEPA Filtered).
After removal of these areas, the specialist RPE was no longer required and operatives could don half mask with organic and dust filtration combined to an APF of 20.
Rhodar and the client then had to establish that the infestation on the floor had not spread. A further one meter of flooring was removed from either side of the contamination and no species were found. It was established that due to the breaking of the linoleum where the racking had been placed this had not allowed the mould to spread.
The mould contaminated floor in the smoke duct was then removed. In the same manner, the flooring in the smoke duct was removed until such time as no contamination was found. Upon the application of the Mould Remover, the species remaining were found to be dead as no reaction was found upon application.
As the linoleum was removed, a salt line along the smoke duct wall was found. This is an indication of the drying out after the flood. The skirting board was removed to reveal heavy black mould and blue green algae contamination up the duct wall. This needed to be removed.
The walls along the smoke duct adjacent to the strong room were removed using hand tools. The plasterboard fire wall was heavily contaminated with mould in a number of areas but the contamination was not following any pattern of infestation. In some areas where the linoleum was contaminated, the board was not and vice-versa.
The contaminated board was removed and then sprayed with the Mould Remover before being double bagged. The waste was then carefully removed at set times to reduce the contact with staff and keeping to routes that could damage or dislodge the books.
All boards were then re-instated to provide the required fire protection in the duct. All floors and walls were cleaned to a high standard using the H Type vacuums.
Once all mould contamination had been removed to the satisfaction of the technical team and the client representative, the area was then subject to two atmospheric decontaminations using the Mould remover through an atomising device. This was to ensure that any airborne spores were removed.
After a contact time of only 120 minutes, the area was safe to enter without (RPE) Respiratory Protective Equipment. Although not required as the chemical used left no residues, the existing shelving was cleaned. Stored racking was then replaced after being cleaned.
After the area was cleared of all enclosure materials and plant, the area was subject to a final clean before returning the area over to the client.
For further information please contact: Andrew Cottrell on a.cottrell@rhodar.co.uk