Section 855.420  Remote Decontamination Enclosure System

a)         A remote worker or equipment decontamination enclosure system may be used when the asbestos abatement work occurring in a contained area in a school is restricted to the removal of nonfriable ACBM by a method which does not cause the ACBM to become friable, or removal of thermal system insulation by use of a glovebag technique.

b)         Worker access to and from a contained area must be through an airlock.

c)         If a worker decontamination enclosure system attached to a contained area is to be used as a remote decontamination enclosure system for work conducted in other contained areas, access to the worker decontamination enclosure system consisting of one of the following methods may be provided, and shall be provided when it is not feasible for the equipment decontamination enclosure system to be used for this purpose:

1)         An airlock attached to the equipment room of the decontamination enclosure system.

2)         A two-stage airlock, consisting of two airlocks in series, which provides access directly to the contained area connected to the worker decontamination enclosure system.

3)         If only nonfriable removal or removal by a glovebag technique is to be conducted in the contaminated area having the attached worker decontamination enclosure system, an airlock attached to the contained area.

d)         Setup of the remote decontamination enclosure system shall be in accordance with Section 855.410.

e)         The remote decontamination enclosure system shall be located inside the separation barriers and shall be in accordance with Section 855.430(b).

f)         The following procedures shall be used with a remote decontamination enclosure system:

1)         Licensed asbestos workers shall don respiratory protection and two pairs of protective coveralls prior to entering the contained removal area.

2)         After completion of the removal and cleaning, the worker shall HEPA vacuum the outer suit, enter the airlock, remove the outer suit and dispose of it as asbestos-contaminated waste.

3)         Still wearing the inner suit and respiratory protection, the worker shall either proceed to another containment, don a second suit and enter, or proceed to the remote decontamination enclosure system.

4)         The remote decontamination enclosure system shall consist of a five chamber unit as illustrated in Section 855.Appendix A, Illustration D.

5)         A HEPA filtered negative air pressure unit shall be attached to the remote decontamination enclosure system at the equipment room end.  The negative air unit shall be exhausted to the exterior of the building and shall operate in accordance with Section 855.380.

6)         The remote decontamination enclosure system shall be wet cleaned after the completion of abatement and have a 12 hour settling period prior to the collection of air samples.

7)         One aggressive air sample shall be taken in the equipment room and analyzed by phase contrast microscopy (PCM) for clearance following USEPA Asbestos Hazard Emergency Response Act (AHERA) clearance standards.  If the decontamination enclosure system does not meet clearance requirements, then the above mentioned procedure shall be repeated until clearance is obtained.