NYC-WTC_000209310

NYC 9/11 Public Portal Document

04/25/02 Liberty Mutual WTC IH Operations

• Remove entrant protective clothing prior to leaving the stairwell area to minimize contamination drag out. Respiratory protection should only be removed when outside of the B2 area.

• Qean the stairwell wall, ceiling, etc. surfaces with a biocide or chlorine solution.

• Require workers performing this stairwell cleaning to wear full face respirators with tri-combination filters and full body coverings. This PPE is needed primarily to provide protection against biocide chemical spray or splatter

• Remediate microbial contamination throu^out WTC 5 B4 and on B2 in the first room on the rij^t room as you enter the loading dock from the j ramp (West) side, as well as any additional areas tliat may be identified moving forward. At a minimum die remediation should follow the NYC guidelines for mold remediation. This work should be performed under the over si^t of an industrial hygienist. liberty Mutual is available to hilfill this role.

• Utilize a contractor with a broad experience remediating microbial contamination including both fungi and bacteria, especially fecal bacteria.

• Conduct a review of at least the following for any contractors being considered to perform the remediation:

• hingi/bacteria remediation work history expenence

• tungi/bactena remediation training and qualifications

• hazard communication program

• medical surveillance program

• respiratory protection program

• PPE programs

• Blood Borne Pathogens program

• waste handling plan

Liberty Mutual industrial hygiene and medical consultation staff are available to assist in thi.s review. It is highly recommended that this service be utilized.

Data Interpretation

The outdoor samples contained 27 and 173 spores per cubic meter of air. (cu.m.) These consisted of Amerospores and Qadosporium. The attached glossary describes the major fungal genii found .

The B4 Vault 1 and Kitchenette contained 322,667 fungal spores/cu.m. and 289,333 fungal spores/cu.m. These consisted of Aspergillus/Penecillium-like spores and Basidiospores (refer to the attached glossary). These lugli levels are considered extremely high as they are in excess of 25,000 times the average outdoor level found on the sampling day'. These levels support the decision to: secure the space, treat entry into the space as a permit required entry, require Tyvek coveralls, ^oves.

’ 'fhe outdoor level found on the sampling day is typical for this area and time of year, per data posted on the .\intrican Academy of Allerg)’ Asthma and Immunology (AAAAI) web site.

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