Law Department notice on WTC document preservation, Oct 2001

NYC 9/11 Public Portal Document

1. Changes to the Health and Safety Plan As a result of changing conditions and new information gained in the field through analytical activities, changes were made to the Health and Safety Plan. The changes related to lead sampling, levels of protection, and use of personal protective equipment. A memorandum concerning detection of cristobalite interference in laboratory results was also incorporated. (See Attachment E).

1.1 Lead Sampling

Air sampling to characterize for exposure of personnel to lead was discontinued on July 24, 2002, because lead in air concentrations consistently presented below the OSHA Action Limit of 30 ug/m3. (29CFR 1926.62).

1.2 Level of Protection

Levels of personal protective equipment (PPE) were changed to reflect exposure measurements. An addendum to the Health and Safety Plan was prepared to address this on September 17,2002. The table below presents the PPE assignments by task, pursuant to original and the amended Health and Safety Plan.

13 Personal Protective Equipment (PPE) By Task

-; iit' Location i ' Original id ?• ; PPE Exclusion 1. Surveying and prep of previously cleaned areas Level C- face Level C- face Zone 2. Surveying and prep of areas not previously cleaned Level C PAPR Level C PAPR 3. Vacuuming with non-HEPA-filtered equipment Level C PAPR Level C PAPR 4. Vacumning with HEPA-filtered equipment in Level C- % face Level C- face previously cleaned areas 5. Wet wiping following non-HEPA vacuuming Level C- ‘A face Level C- face 6. Wet wiping following HEPA vacuuming Level D+ Level D+ 7. Cleaning equipment using air and vacuiun Level C PAPR Level CPAPR 8. Removing/ changing vacuum bags and filters Level C PAPR Level C PAPR 9. Re-cleaning units w/HEPA vacumning and New Task Level D+ supporting personal air sampling results 10. Re-cleaning units w/ non-HEPA vacuuming New Task Level C- face 11. Re-cleaning units w/HEPA vacuuming without supporting personal air sampling results New Task Level C- ‘4 face

1.4 Use of Goggles

Goggles were assigned for Levels D and D+ because of concerns that irritation of employee’s eyes might result from airborne fiberglass. Once it was determined that eye irritation was not occurring, safety glasses were substituted.

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