Register March 2010 No. 651
APPENDIX H
PROTECTING OCCUPANTS
Chapter 8, HUD Guidelines for the Evaluation and Control of
Lead-Based Paint Hazards in Housing
____________________________
Step-by-Step Summary
Resident Protection and Worksite Preparation: How To Do It
1. If possible, perform the work in a vacant unit. If residents must remain inside the dwelling during work, erect appropriate barrier systems as described in the tables in this chapter.
2. Permit residents to reenter the work area only after work is complete and visual inspection has been completed and dust samples collected. If the work is not completed at the end of the day, keep the barriers in place overnight and instruct residents not to enter the work area.
3. Determine if the dwelling will require precleaning before worksite containment. If the paint is severely deteriorated and there are paint chips present, the paint chips should be removed by HEPA vacuuming before plastic is laid down.
4. Determine requirements for relocation, isolation of work areas, and other worksite preparation measures based on the type and extent of the work and the amount of dust that will be generated.
5. Select an Interior Worksite Preparation Level, an Exterior Worksite Preparation Level, and/or a Window Worksite Preparation Level (depending on the work required) from the tables in this chapter.
6. Conduct daily cleanup.
7. Perform a visual examination daily.
8. Conduct dust sampling as specified in this chapter.
9. Never permit residents to enter a work area where lead hazard control work is under way. Entry should be denied until cleaning and clearance have been completed.
Chapter 8: Resident Protection and Worksite Preparation
I. Introduction
Lead hazard control methods generate varying amounts of leaded dust, paint chips, and other lead-contaminated materials. This chapter describes ways to protect residents and the environment from exposure to, or contamination from, these materials. Some processes require complete isolation of the work area and/or full evacuation of the residents and their belongings, while other methods require little or no containment. Containment refers to various methods of preventing leaded dust from migrating beyond the work area. It includes everything from the simple use of disposable plastic drop cloths to the sealing of openings with plastic sheeting. The required degree of containment depends upon a number of considerations (e.g., type of hazard control, resident relocation possibilities, size of work area, etc.). Generally speaking, significant lead hazard control work should be performed in vacant units, with only small-scale activity conducted in occupied units. Worksite preparation is needed for both interim control and abatement work.
This chapter describes the general principles behind resident protection and proper worksite preparation. Three tables are included: one for interior work, one for exterior work, and one for windows. Guidance is also offered for certified abatement supervisors, risk assessors, and project planners on the development of a written occupant protection plan, which may be required by some agencies.
II. Resident Entry Into Work Area Prohibited
Regardless of the extent of the work, residents must never be permitted to enter the work area while work is under way, even if the work only disturbs a small area. Resident reentry into the work area is permitted only after the area has been cleaned and has passed clearance. All of the work-site preparation strategies discussed in this chapter are based on this fundamental requirement. While residents may not be present inside the work area, it is possible for them to remain inside other parts of the dwelling during some types of work, or to leave for the day and return to the dwelling at night after cleaning and visual evaluation, and collection of dust samples. In cases of hardship where the resident must occupy the area prior to receiving laboratory results of clearance dust samples, occupancy should not occur until visual inspection has been completed and dust samples collected.
III. Site Assessment and Precleaning
The certified lead hazard control supervisor should ensure that the dwelling is structurally sound. If structural deficiencies exist, they must be corrected before the site can be prepared for lead hazard control (see Figure 8.1). Environmental and worker protection must be provided if the structural repairs will involve disturbance of surfaces coated with lead-based paint.
If the paint is severely deteriorated and there are numerous paint chips on the floors, the paint chips should be removed by high-efficiency particulate air (HEPA) vacuuming before any plastic is laid down (see Figure 8.2). Vacuuming will prevent the paint chips from being ground into dust by the workers' feet. Wet washing usually is not required for precleaning.
IV. Debris Control
The only way that lead hazard control work can proceed safely in
occupied dwellings is to ensure that cleaning is completed before residents reenter the unit. Cleaning is especially important when residents are present in the dwelling while work is in progress, or when residents return in the evening after work has been completed for the day. Neither debris nor plastic sheeting may be left outside the dwelling overnight or in any area where passersby or children could come into contact with these materials. All debris must be handled in accordance with the standards outlined in Chapter
10. When residents cannot be relocated and work must proceed room by room, clearance standards may be more difficult to meet, since dust from moved furniture may cause recontamination.
V. Worksite Preparation Levels
A. Worksite Preparation Level Selection
When planning a lead hazard control job, the worksite preparation levels listed in Tables 8.1, 8.2, and 8.3 should be considered. Since each worksite is unique, it is necessary to pick the level that is the most cost-effective for each specific situation. This judgment should be made by a certified risk assessor, a certified abatement supervisor, or a trained lead-based paint planner/designer. The tables provide guidance on choosing the appropriate preparation level for each job.
The necessary worksite preparation level will depend on:
* The size of the surface(s) needing work.
* The type of hazard control methods to be used.
* The extent of existing contamination.
* The building layout.
* The vacancy status of the dwelling.
* The types of worker protection needed.
* The need for other construction or abatement work (e.g., renovation or asbestos abatement).
A certified individual should weigh all of these issues in determining which level of preparation is appropriate for a given situation. For example, the enclosure of walls will probably require a lower worksite preparation level than the wet scraping of a large area, since enclosure will generate less dust. Similarly, deteriorated component replacement (demolition work) will probably require a higher containment level than the wet scraping of a small area.
These Guidelines are performance-oriented and are not specifications. It is possible to select elements from different worksite preparation levels to devise a unique worksite preparation plan for an individual dwelling. Whatever combination of containment measures is selected, the levels of leaded dust outside the containment area must not rise above clearance levels. Containment measures should be designed to prevent the release of leaded dust, which can be spread by workers' shoes or by airborne dust. A previously conducted risk assessment will indicate if hazardous leaded dust levels exist outside the containment area. If such a problem was identified and if leaded dust levels rise in the course of the work, it is reasonable to conclude that the dust was released from the containment area and that the containment system is ineffective. Dust sampling is usually conducted no further than 10 feet away from the containment area. If deviations from the worksite preparation plans described below are contemplated, then the performance of the containment system should be determined by a certified risk assessment professional. This flexibility permits owners to select the most cost-effective strategy, while also protecting the public health and the environment.
B. Hazard Control Work in Occupied Dwellings
If bathrooms are not accessible, residents should always be relocated during the day (Table 8.1, Level 2 at a minimum) unless alternative arrangements can be made (e.g., use of a neighbor's bathroom). In addition, if construction will result in other hazards (such as exposed electric wires), then residents should also be relocated.
If a worksite preparation level is selected that permits residents either to remain inside the dwelling while work is being conducted or return to the dwelling in the evening after work has been completed, then a dust sample should be collected from the living area at greatest risk of contamination (usually the living area adjacent to the work area) at the end of each work day. It is essential that the sample be collected before the work area is cleaned to determine if the containment system protected the occupants that day. If the leaded dust level is above clearance standards, residents must be relocated immediately and must not be allowed to reenter the dwelling until cleanup and documented compliance with clearance standards is achieved.
If the same work crew and supervisor can document compliance with these criteria for three or more consecutive dwelling units using the same hazard control techniques, then dust sampling frequency can be reduced to 1 in every 20 dwellings for that crew.
C. Worksite Preparation Level Definitions
Tables 8.1 and 8.2 define interior and exterior worksite preparation levels. There are four levels for the preparation of dwelling interiors and three levels for the preparation of dwelling exteriors. The lowest levels are primarily designed for interim control activities, while the highest levels are designed for the dustiest abatement methods. Table 8.3 describes worksite preparation as it applies specifically to windows (this technique could be performed from either the interior or exterior of the dwelling). The plastic sheeting in the tables refers to polyethylene plastic sheeting that is at least 6 mils thick (or equivalent). These recommendations represent the best guidance that can be offered at this time. Worksite preparation levels should be designed on a site-by-site basis.
VI. Relocation Dwellings
Relocation dwellings should be acceptable to residents so that they will not attempt to return to their own dwellings during lead hazard control work. Dwellings serving as temporary relocation units must be lead safe. In addition, these units should be adequately equipped with furniture, cooking facilities, refrigerators, televisions, and toys (unless these items will be moved with the resident). Relocation is usually a substantial undertaking, involving not only the movement of people and their possessions, but also the coordination of mail, phone, school, and community changes. Whenever possible, children should continue to attend the same school during the relocation period, even though this may involve finding special transportation. Due to their complex nature, relocation considerations may dictate the scheduling of the project.
VII. Negative Pressure Zones (“Negative Air" Machines)
In asbestos abatement work and lead-based paint removal work on structural steel, it is common to create work sites that are under negative pressure in comparison to the outside of the containment structure. A negative pressure zone is usually created by blowing air out of the work area through a HEPA filter, while air intake is restricted to a lower flow rate than exhaust. This process causes air to leak into the containment area instead of out of the containment area, and reduces dust fall and worker exposure by removing contaminants from the airstream through constant filtration.
Due to the different aerodynamics of leaded dust particles and asbestos fibers, negative pressure zones do not appear to be necessary for most forms of residential lead hazard control work. No effect on airborne lead levels, either inside or outside the containment area, has been associated with the use of an air filtration device commonly known as a “negative air" machine (NIOSH, 1993a). In addition, no effect on cleanup efficiency was noted. Most lead-based paint abatement projects in the public housing program have not found it necessary to use negative air machines. Therefore, the added expense of requiring negative pressure zones for general residential lead-based paint hazard control work does not appear to be justified. However, there are two specific situations where the use of a negative pressure zone would be appropriate in a residential setting.
The first case involves floor sanding. Even if the paint has already been removed, leaded dust generation is likely to be quite high due to residual dust in the flooring. Enclosing old flooring with new flooring is the recommended course of action. However, if old flooring must be restored, then negative pressure zones should be established. At least 10 air changes per hour should be provided and all exhaust air must be passed through a HEPA filter.
