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SECTION V: CHAPTER 3 

CONTROLLING LEAD EXPOSURES IN THE CONSTRUCTION INDUSTRY: ENGINEERING AND 

WORK PRACTICE CONTROLS

Contents:

I. INTRODUCTION. 

A. This chapter provides OSHA compliance officers and safety and health professionals with 

general information on the types of construction activities involving worker exposure to lead 

and the feasible engineering and work practice controls to reduce these exposures. The 

construction activities identified range from those such as abrasive blasting and welding, 

cutting, and burning, where exposures to lead are often high, to encapsulating lead-based 

paint or using lead pots, where exposures are generally low. 

B. The material in this chapter will help OSHA compliance officers and safety and health 

professionals apply their resources to the industrial-hygiene problems associated with lead 

exposures in the construction industry. General engineering and work practice controls that 

can be applied to almost any construction activity are addressed under Paragraph II, below. 

C. This chapter also describes those lead-related tasks and operations that give rise to lead 

exposures among construction workers. Recommended/feasible engineering controls (e.g., 

isolation, substitution, change of process, wet methods, local exhaust ventilation, general 

ventilation) are then discussed for each task or operation, along with work practice controls 

that are unique to these activities. 

D. The current OSHA standard (29 CFR 1926.62) for lead exposure in construction has a 

permissible exposure limit (PEL) of 50 micrograms per cubic meter of air (50 μg/m3), measured 

as an 8-hour time-weighted average (TWA). As with all OSHA health standards, when the PEL 

is exceeded, the hierarchy of controls requires employers to institute feasible engineering and 

work practice controls as the primary means to reduce and maintain employee exposures to 

levels at or below the PEL. When all feasible engineering and work practice controls have been 

implemented but have proven inadequate to meet the PEL, employers must nonetheless 

implement these controls and must supplement them with appropriate respiratory protection. 

The employer also must ensure that employees wear the respiratory protection provided when 

it is required. 

E. Certain lead-related construction tasks commonly produce exposures above the PEL and often 

I. 

II. 

III. 

IV.

Introduction

Engineering and Work Practice Controls

Operations

Bibliography

Appendix V:3-1. Lead-Related Construction Tasks and Their Presumed 8-Hour TWA 

Exposure Levels

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orders of magnitude above the PEL. The OSHA lead standard for construction is unique in that 

it groups tasks (Appendix V:3-1) that are presumed to be associated with employee exposures 

above the PEL into three lead-exposure ranges. The exposure ranges assigned to the different 

categories of tasks are based on data collected by OSHA and other sources including two 

advisory groups. 

F. Until an employer performs an employee-exposure assessment and determines the magnitude 

of the exposures actually occurring during the lead-related activity, the employer must assume 

that employees performing that task are exposed to the lead concentrations indicated in 

Appendix V:3-1.For all three groups of tasks, employers are required to provide respiratory 

protection appropriate to the task's presumed exposure level, protective work clothing and 

equipment, change areas, hand-washing facilities, training, and the initial medical surveillance 

prescribed by paragraph (d)(2)(v) of the standard (29 CFR 1926.62). The only difference in the 

provisions applying to the three categories of tasks is the degree of respiratory protection 

required. 

II. ENGINEERING AND WORK PRACTICE CONTROLS. 

A. ENGINEERING CONTROLS. Engineering controls, such as ventilation, and good work 

practices are the preferred methods of minimizing exposures to airborne lead at the worksite. 

The engineering control methods that can be used to reduce or eliminate lead exposures can 

be grouped into three main categories: (1) substitution; (2) isolation; and (3) ventilation. 

Engineering controls are the first line of defense in protecting workers from hazardous 

exposures. 

1. Substitution. 

a. Substitution includes using a material that is less hazardous than lead, changing 

from one type of process equipment to another, or even, in some cases, changing the 

process itself to reduce the potential exposure to lead. In other words, material, 

equipment, or an entire process can be substituted to provide effective control of a lead 

hazard. However, in choosing alternative methods, a hazard evaluation should be 

conducted to identify inherent hazards of the method and equipment. 

b. Examples of substitution include: 

 Use of a less hazardous material: applying a nonleaded paint rather than a 

coating that contains lead. 

 Change in process equipment: using less dusty methods such as vacuum 

blast cleaning, wet abrasive blast cleaning, shrouded power tool cleaning, or 

chemical stripping to substitute for open abrasive blast cleaning to reduce 

exposure to respirable airborne particulates containing lead. 

 Change in process: performing demolition work using mobile hydraulic shears 

instead of a cutting torch to reduce exposure to lead fumes generated by 

heating lead compounds. 

c. Any material that is being considered as a substitute for a lead-based paint should 

be evaluated to ensure that it does not contain equally or more toxic components (e.g., 

cadmium or chromates). Because substitute materials can also be hazardous, employers 

must obtain a Material Safety Data Sheet (MSDS) before a material is used in the 

workplace. If the MSDS identifies the material as hazardous, as defined by OSHA's 

hazard communication standard (29 CFR 1926.59), an MSDS must be maintained at the 

job site and proper protective measures must be implemented prior to usage of the 

material. 

2. Isolation is a method of limiting lead exposure to those employees who are working 

directly with it. A method which isolates lead contamination and thus protects both 

nonessential workers, bystanders, and the environment is to erect a sealed containment 

structure around open abrasive blasting operations. However, this method may 

substantially increase the lead exposures of the workers doing the blasting inside the 

structure. The containment structure must therefore be provided with negative-pressure 

exhaust ventilation to reduce workers' exposure to lead, improve visibility, and reduce 

emissions from the enclosure. 

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3. Ventilation. 

a. Ventilation, either local or dilution (general), is probably the most important 

engineering control available to the safety and health professional to maintain airborne 

concentrations of lead at acceptable levels. Local exhaust ventilation, which includes 

both portable ventilation systems and shrouded tools supplied with ventilation, is 

generally the preferred method. If a local exhaust system is properly designed, it will 

capture and control lead particles at or near the source of generation and transport 

these particles to a collection system before they can be dispersed into the work 

environment. 

b. Dilution ventilation, on the other hand, allows lead particles generated by work 

activities to spread throughout the work area and then dilutes the concentration of 

particles by circulating large quantities of air into and out from the work area. For work 

operations where the sources of lead dust generation are numerous and widely 

distributed (e.g., open abrasive blasting conducted in containment structures), dilution 

ventilation may be the best control. 

c. Examples of ventilation controls include the following: 

 Power tools that are equipped with dust collection shrouds or other attachments 

for dust removal and are exhausted through a HEPA vacuum system. 

 Vacuum blast nozzles (vacuum blasting is a variation on open abrasive blasting). 

In this type of blasting, the blast nozzle has local containment (a shroud) at its 

end, and containment is usually accomplished through brush-lined attachments 

at the outer periphery and a vacuum inlet between the blast nozzle and the 

outer brushes. Containment structures that are provided with negative-pressure 

dilution ventilation systems to reduce airborne lead concentrations within the 

enclosure, increase visibility, and control emissions of particulate matter to the 

environment. 

B. WORK PRACTICE CONTROLS. Work practices involve the way a task is performed. OSHA 

has found that appropriate work practices can be a vital aid in lowering worker exposures to 

hazardous substances and in achieving compliance with the PEL. Some fundamental and easily 

implemented work practices are: (1) good housekeeping, (2) use of appropriate personal 

hygiene practices, (3) periodic inspection and maintenance of process and control equipment, 

(4) use of proper procedures to perform a task, (5) provision of supervision to ensure that the 

proper procedures are followed, and (6) use of administrative controls. 

1. Housekeeping. 

a. A rigorous housekeeping program is necessary in many jobs to keep airborne lead 

levels at or below permissible exposure limits. Good housekeeping involves a regular 

schedule of housekeeping activities to remove accumulations of lead dust and 

lead-containing debris. The schedule should be adapted to exposure conditions at a 

particular worksite. 

b. All workplace surfaces must be maintained as free as practicable of accumulations of 

lead dust. Lead dust on overhead ledges, equipment, floors, and other surfaces must be 

removed to prevent traffic, vibration, or random air currents from re-entraining the 

lead-laden dust and making it airborne again. Regularly scheduled clean-ups are 

important because they minimize the re-entrainment of lead dust into the air, which 

otherwise serves as an additional source of exposure that engineering controls are 

generally not designed to control. 

c. Vacuuming is considered the most reliable method of cleaning dusty surfaces, but 

any effective method that minimizes the likelihood of re-entrainment may be used (for 

example, a wet floor scrubber). When vacuuming equipment is used, the vacuums must 

be equipped with high-efficiency particulate air (HEPA) filters. Blowing with compressed 

air is generally prohibited as a cleaning method, unless the compressed air is used in 

conjunction with a ventilation system that is designed to capture the airborne dust 

created by the compressed air (e.g. dust "blowdown" inside a negative-pressure 

containment structure). In addition, all persons doing the cleanup should be provided 

with suitable respiratory protection and personal protective clothing to prevent contact 

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with lead. 

d. Where feasible, lead-containing debris and contaminated items accumulated for 

disposal should be wet-misted before handling. Such materials must be collected and 

put into sealed impermeable bags or other closed impermeable containers. Bags and 

containers must be labeled to indicate that they contain lead-containing waste. 

2. Personal Hygiene Practices. 

a. Personal hygiene is also an important element in any program to protect workers 

from exposure to lead dust. When employee exposure is above the PEL, the lead 

standard requires the employer to provide, and ensure that workers use, adequate 

shower facilities (where feasible), hand-washing facilities, clean change areas, and 

separate noncontaminated eating areas. Employees must also wash their hands and 

faces prior to eating, drinking, using tobacco products, or applying cosmetics, and they 

must not eat, drink, use tobacco products, or apply cosmetics in any work area where 

the PEL is exceeded. In addition, employees must not enter lunchroom facilities or 

eating areas while wearing protective work clothing or equipment unless surface lead 

dust has first been removed from the clothing or equipment by vacuuming or another 

cleaning method that limits dispersion of lead dust. 

b. Workers who do not shower and change into clean clothing before leaving the 

worksite may contaminate their homes and vehicles with lead dust. Other members of 

the household may then be exposed to harmful amounts of lead. A recent NIOSH 

publication (NIOSH 1992) points out the dangers of "take-home" lead contamination. 

For the same reason, vehicles driven to the worksite should be parked where they will 

not be contaminated with lead. 

c. The personal hygiene measures described above will reduce worker exposure to lead 

and decrease the likelihood of lead absorption caused by ingestion or inhalation of lead 

particles. In addition, these measures will minimize employee exposure to lead after the 

work shift ends, significantly reduce the movement of lead from the worksite, and 

provide added protection to employees and their families. 

3. Change Areas. 

a. When employee airborne exposures to lead are above the PEL, the employer must 

provide employees with a clean change area that is equipped with storage facilities for 

street clothes and a separate area with facilities for the removal and storage of 

lead-contaminated protective work clothing and equipment. Separate clean and dirty 

change areas are essential in preventing cross-contamination of the employees' street 

and work clothing. 

b. Clean change areas are used to remove street clothes, to suit up in clean work 

clothes (protective clothing), and to don respirators prior to beginning work, and to 

dress in street clothes after work. No lead-contaminated items are permitted to enter 

the clean change area. Work clothing should be worn only on the job site. Under no 

circumstances should lead-contaminated work clothes be laundered at home or taken 

from the worksite, except to be laundered professionally or properly disposed of 

following applicable Federal, State, and local regulations. 

4. Showers. When employee exposures exceed the PEL, the employer must provide 

employees with suitable shower facilities, where feasible, so that exposed employees 

can remove accumulated lead dust from their skin and hair prior to leaving the worksite. 

Where shower facilities are available, employees must shower at the end of the work 

shift before changing into their street clothes and leaving the worksite. Showers must 

be equipped with hot and cold water, in accordance with 29 CFR 1926.51(f)(4)(iv). 

5. Washing Facilities. Washing facilities must be provided to employees in accordance 

with the requirements of 29 CFR 1926.51(f). Water, soap, and clean towels are to be 

provided for this purpose. Where showers are not provided, the employer must ensure 

that employees wash their hands and faces at the end of the work shift. 

6. Eating Facilities. The employer must provide employees who are exposed to lead at 

levels exceeding the PEL with eating facilities or designated areas that are readily 

accessible to employees and must ensure that the eating area is free from lead 

contamination. To further minimize the possibility of food contamination and reduce the 

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likelihood of additional lead absorption from contaminated food, beverages, tobacco, 

and cosmetic products, the employer must prohibit the storage, use, or consumption of 

these products in any area where lead dust or fumes may be present. 

7. Periodic Inspection and Maintenance. Periodic inspection and maintenance of 

process equipment and control equipment such as ventilation systems are another 

important work practice control. At worksites where full containment is used as an 

environmental control, the failure of the ventilation system for the containment area can 

result in hazardous exposures to workers within the enclosure. Equipment that is near 

failure or in disrepair will not perform as intended. Regular inspections can detect 

abnormal conditions so that timely maintenance can be performed. If process and 

control equipment is routinely inspected, maintained, and repaired, or is replaced before 

failure occurs, there is less chance that hazardous employee exposures will occur. 

8. Performance of Task. 

a. In addition to the work practice controls previously described in Section B, the 

employer must provide training and information to employees as required by OSHA's 

lead in construction (29 CFR 1926.62), hazard communication (29 CFR 1926.59), and 

safety training and education (29 CFR 1926.21) standards. One important element of 

this program is training workers to follow the proper work practices and procedures for 

their jobs. Workers must know the proper way to perform job tasks to minimize their 

exposure to lead and to maximize the effectiveness of engineering controls. For 

example, if a worker performs a task away from (rather than close to) an exhaust hood, 

the control measure will be unable to capture the particulates generated by the task 

and will thus be ineffective. 

b. In certain applications such as abatement in buildings, wet methods can significantly 

reduce the generation of lead-containing dust in the work area. Wetting of surfaces 

with water mist prior to sanding, scraping, or sawing, and wetting lead-containing 

building components prior to removal will minimize airborne dust generation during 

these activities. Failure to operate engineering controls properly may also contaminate 

the work area. Workers can be informed of safe operating procedures through fact 

sheets, discussions at safety meetings, and other educational means. 

9. Supervision. 

a. Good supervision is another important work practice. It provides needed support for 

ensuring that proper work practices are followed by workers. By directing a worker to 

position the exhaust hood properly or to improve work practice, such as standing to the 

side or upwind of the cutting torch to avoid the smoke plume, a supervisor can do much 

to minimize unnecessary employee exposure to airborne contaminants. 

b. The OSHA construction standard for lead also requires that a competent person 

perform frequent and regular inspections of job sites, materials, and equipment. A 

competent person is defined by the standard as one who is capable of identifying 

existing and predictable lead hazards and who has authorization to take prompt 

corrective measures to eliminate them. 

10. Administrative Controls. 

a. Administrative controls are another form of work practice controls that can be used 

to influence the way a task is performed. Controls of this type generally involve 

scheduling of the work or the worker. For example, employee exposure can be 

controlled by scheduling construction activities or workers' tasks in ways that minimize 

employee exposure levels. One method the employer can use is to schedule the most 

dust- or fume-producing operations for a time when the fewest number of employees 

will be present. 

b. Another method is worker rotation, which involves rotating employees into and out 

of contaminated areas in the course of a shift, thereby reducing the full-shift exposure 

of any given employee. When a worker is rotated out of the job that involves lead 

exposure, he or she is assigned to an area of the worksite that does not involve lead 

exposure. If this method is used to control worker exposure to lead, the lead standard 

requires that the employer implement a job rotation schedule that (1) identifies each 

affected worker, (2) lists the duration and exposure levels at each job or work station 

where each affected employee is located, and (3) lists any other information that may 

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be useful in assessing the reliability of administrative controls to reduce exposure to 

lead. 

III. OPERATIONS. 

This section describes the job operations that take place in construction worksites and involve worker 

exposures to lead. Although this list of operations is extensive, it is not necessarily inclusive (i.e, other 

construction activities not mentioned here may also involve lead exposure). OSHA's lead standard for 

construction applies to any construction activity that potentially exposes workers to airborne 

concentrations of lead. 

A. OPEN ABRASIVE BLAST CLEANING. 

1. The most common method of removing lead-based paints is open abrasive blast 

cleaning. The abrasive medium, generally steel shot/grit, sand, or slag, is propelled 

through a hose by compressed air. The abrasive material abrades the surface of the 

structure, exposing the steel substrate underneath. The abrasive also conditions the 

substrate, forming a "profile" of the metal, which improves the adherence of the new 

paint. Work is generally organized so that blasting proceeds for approximately one-half 

day, followed by compressed air cleaning of the steel and application of the prime coat 

of paint. Prime coat painting must follow blasting immediately to prevent surface rust 

from forming. Intermediate or finish coats of paint are applied later. 

2. Structures that are typically cleaned by open abrasive blasting are bridges, tanks and 

towers, locks and dams, pipe racks, pressure vessels and process equipment, 

supporting steel, and metal buildings. Until recently, abrasive blasting work was 

conducted in unobstructed air. The free circulation of wind and air helped to reduce the 

airborne concentration of lead-containing dust in the workers' breathing zone. 

Tarpaulins were generally used only to protect neighboring homes and automobiles 

from a damaging blast of abrasive or to reduce residents' complaints about overspray, 

dust, and dirt. Currently, some state and local regulations require the use of enclosures 

or containment structures to prevent the uncontrolled dispersal of lead dust and debris 

into the environment. Although containment structures are designed to reduce the 

dispersion of lead into the environment, they usually increase worker exposure to 

airborne lead, reduce visibility, and increase the risk of slip and fall injuries due to waste 

material build-up on the footing surface of the enclosure. 

3. Containment structures vary in their design and in their effectiveness in containing 

debris. Some containment structures consist of tarpaulins made of open mesh fabrics 

(screens) that are loosely fitted around the blasting area; some use rigid materials such 

as wood, metal, or plastic to enclose the blasting area; and some use a combination of 

flexible and rigid materials. Large air-moving devices may be connected to the enclosed 

containment structure to exhaust dust-laden air and create a negative pressure with 

respect to the ambient atmosphere. 

4. Containment or enclosure structures can be broadly classified as either partial or full. 

Partial containments refer to those that inherently allow some level of emission to the 

atmosphere outside of the containment. An example of a partial containment is a 

structure with loosely hung permeable tarps and artially sealed joints and entryways. 

Full containment refers to a relatively tight enclosure (with tarps that are generally 

impermeable and fully sealed joints and entryways) where minimal or no fugitive 

emissions are expected to reach the outside environment. Partial or full containments 

can be used to contain entire structures or portions thereof. Examples of the kinds of 

engineering controls and work practices that can be implemented to protect blasting 

workers are presented below. 

5. Engineering Controls. 

a. Containment/ventilation systems should be designed and operated so as to create a 

negative pressure within the structure, which reduces the dispersion of lead into the 

environment. The containment/ventilation system should be designed to optimize the 

flow of ventilation air past the worker(s), thereby reducing the airborne concentration of 

lead and increasing visibility. This can be accomplished by employing either a downdraft 

or crossdraft ventilation system that is properly balanced by a make-up air supply. 

Designs for the containment structure and ventilation systems should be specific to 

each task, because conditions can vary substantially from one worksite to another. The 

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dust-laden air must be filtered prior to its release into the atmosphere. 

b. Mini-enclosures, which have smaller cross-sectional areas than conventional 

enclosures, can be erected. Mini-enclosures have advantages over larger conventional 

enclosures because the same size fan and dust collector can achieve much higher 

velocities past the helmets of the workers. Mini-enclosure containment structures are 

usually light-weight, low wind-loading structures that isolate that area where blasting 

and surface priming is taking place on a given day. 

c. The risk of silicosis is high among workers exposed to abrasive blasting with 

silica-containing media, and this hazard is difficult to control. The National Institute for 

Occupational Safety and Health (NIOSH) has therefore recommended since 1974 that 

silica sand (or other substances containing more than 1% crystalline silica) be 

prohibited as abrasive blasting material. A variety of materials such as slags and steel 

grit are available as alternative blasting media. Because some substitute materials may 

have their own unique hazards, the MSDS for the substitute material should be 

consulted before it is used. 

d. Blast cleaning with recyclable abrasive such as steel grit or aluminum oxide requires 

specialized equipment for vacuuming or collecting the abrasive for reuse, separating the 

lead dust and fines from the reusable abrasive, and, in the case of steel grit, 

maintaining clean, dry air to avoid rusting of the abrasive. In addition, the abrasive 

classifier must be extremely efficient in removing lead dust, to prevent it from being 

reintroduced into the containment and combining with the paint to increase worker 

exposures. Recycling equipment must be well-maintained and regularly monitored to 

ensure it is removing lead effectively. 

e. When site conditions warrant, less dusty methods should be used in place of open 

abrasive blast cleaning. These include: 

 Vacuum-blast cleaning; 

 Wet abrasive blast cleaning; 

 High-pressure water jetting; 

 High-pressure water jetting with abrasive injection; 

 Ultrahigh-pressure water jetting; 

 Sponge jetting; 

 Carbon-dioxide (dry-ice) blasting; 

 Chemical stripping; and 

 Power-tool cleaning. 

6. Work Practice Controls. Construction employers engaged in open abrasive blast 

cleaning operations should implement the following control measures: 

 Develop and implement a good respiratory protection program in accordance 

with OSHA requirements in 29 CFR 1926.103. 

 Provide workers with Type CE abrasive-blast respirators; these are the only 

respirators suitable for use in abrasive-blasting operations. Currently there are 

only three models of Type CE abrasive blast respirators certified by MSHA/ 

NIOSH: 

- A continuous-flow respirator with a loose-fitting hood that has 

 a protection factor of 25; 

- A continuous-flow respirator with a tight-fitting face-piece 

 that has a protection factor of 50; and 

- A pressure-demand respirator with a tight-fitting face-piece 

 that has a protection factor of 2000. 

The first two models (i.e. the continuous-flow respirators) should be used only for 

abrasive blast operations where the abrasive materials do not include silica sand and 

the level of contaminant in the ambient air does not exceed 25 or 50 times the 

recommended exposure limit, respectively. The third model, which is a 

pressure-demand respirator, must be worn whenever silica sand is used as an abrasive 

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material (NIOSH 1993). In addition, ensure to the extent possible that workers are 

upstream from the blasting operation to reduce their exposure to lead dust entrained in 

the ventilation air. 

B. VACUUM BLAST CLEANING. 

1. Vacuum blasting is a variation of open abrasive blasting. In this configuration, the blast 

nozzle has local containment (a shroud) at its end and containment is usually 

accomplished by brush-lined attachments at the outer periphery and a vacuum inlet 

between the blast nozzle and the outer brushes (Waagbo and McPhee 1991). The 

brushes prevent dispersion of the abrasive and debris as they rebound from the steel 

surface. These particles are removed from the work area by the built-in vacuum system. 

The abrasive itself can either be disposed of or cleaned and recycled. 

2. If used properly, vacuum blast cleaning can achieve cleaning of good quality with 

minimal dust generation except in areas where access is difficult because of 

configuration (such as between back-to-back angles). A variety of heads are available to 

achieve a tight seal for inside corners, outside corners, and flat surfaces. The 

advantages of vacuum blasting are that most of the waste material and abrasive is 

collected at the site of generation and is therefore not transported to the breathing 

zone of the worker, and that there may be little or no need for containment. 

3. Vacuum blasting has several disadvantages (Knoy 1990). It is more time-consuming 

than conventional open abrasive blasting because the abrasive blast nozzle must be 

smaller to be able to capture the ricocheting abrasive and dust. This restricts the 

dispersion of the abrasive and thus the size of the area that can be cleaned. Abrasive 

also may escape the vacuum head if the brush attachments do not seal completely 

around the substrate; poor seals may be caused by operator fatigue, poor work 

practices or irregular surfaces and edges. Small areas and areas with gross irregularities 

cannot be effectively sealed by the shroud. The vacuum system and brushes obscure 

the blast surface, and some areas may therefore need to be blasted repeatedly because 

they are missed on the first or second pass. In addition, some vacuum heads are so 

heavy that mechanical suspension systems are needed to support them, and even then, 

the blasters may need to take frequent breaks. 

C. WET ABRASIVE BLAST CLEANING. 

1. Wet abrasive blast cleaning is a modification of traditional open abrasive blast cleaning. 

This system uses compressed air to propel the abrasive medium to the surface being 

cleaned; however, water (which reduces dusting) is injected into the abrasive stream 

either before or after the abrasive exits the nozzle (Figure V:3-1). FIGURE V:3-1. WET 

ABRASIVE BLAST CLEANING.

 

2. The disadvantages of using water are that inhibitors may be necessary to avoid flash 

rusting, the containment must be designed to capture the water and debris generated 

by the cleaning process, wet abrasive/paint debris is more difficult to handle and 

transport than dry debris, and, unless the water can be filtered, it may add to the 

volume of debris generated. 

3. Because many corrosion inhibitors (e.g., nitrates, nitrites, and amines) raise industrial 

hygiene concerns, their use must be considered carefully. 

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D. HIGH-PRESSURE WATER JETTING. 

1. High-pressure water jetting (6,000 to 25,000 psi) utilizes a pressure pump, a large 

volume of water, a specialized lance and nozzle assembly and, in some cases, a supply 

of inhibitor to prevent flash rusting. High-pressure water can remove loose paint and 

rust, but will not efficiently remove tight paint or tight rust, or mill scale. This technique 

does not create a profile (mechanically induced toothing pattern to enhance the 

adhesion of high-performance coatings) on its own, but if the original surface was blast 

cleaned, high-pressure water jetting can be used to remove the old paint and restore 

the original profile. 

2. Because of the water, this kind of jetting generates little dust. The containment must be 

constructed to collect water rather than to control dust emissions. The debris generated 

is comprised of the removed paint and rust, along with the water. If the lead debris can 

be adequately filtered from the water, the volume of debris is low. If not, the volume of 

debris can be high. Typically, five to ten gallons of water per minute are used. 

3. Productivity can be high with this method if the objective is to remove only loose, flaky 

paint. If the objective is to remove tight paint, productivity may be low. However, both 

productivity and the ability to remove tight paint, rust, and mill scale can be improved 

through the addition of abrasive to the water stream. 

E. HIGH-PRESSURE WATER JETTING WITH ABRASIVE INJECTION. 

1. This system uses an expendable abrasive that is metered into a pressurized water jet 

(6,000 to 25,000 psi) for surface preparation. Although airborne lead exposures are 

virtually eliminated with this approach, wet abrasive is more difficult to handle and 

move than dry abrasive, and the volume of debris also increases. Because the abrasive 

exposes the bare substrate, inhibitors such as sodium nitrate or amines are often added 

to the water to prevent flash rusting. 

2. Abrasives used for injection include sand and slag materials, as well as soluble abrasives 

such as sodium bicarbonate. The sodium bicarbonate will not remove paint, rust, and 

mill scale as efficiently as sand or slag abrasives. However, the advantage of sodium 

bicarbonate is that the abrasive is water soluble and, if the lead can be filtered from the 

water, the volume of debris is reduced because the dissolved bicarbonate is not 

considered hazardous. 

F. ULTRAHIGH-PRESSURE WATER JETTING. 

1. Ultrahigh-pressure water jetting utilizes pressurized water at pressures in excess of 

25,000 psi. Ultrahigh-pressure water jetting is similar to high pressure water jetting 

except that the ultrahigh variant uses even higher pressures. This means that it cleans 

more efficiently and removes tight paint and rust more effectively. In addition, the 

volume of water required is reduced, with less than five gallons per minute typically 

used. Because of the water, little dust is generated. 

2. The greatest disadvantage of this process is the difficulty of collecting the contaminated 

water; wherever the water goes, it carries debris with it. Dust generation, debris 

generation, and the type of containment necessary in ultrahigh-pressure water jetting 

are comparable to those in high-pressure water jetting. Inhibitors are also often 

required to avoid flash rusting. Mill scale is not removed; however, if the surface was 

previously blast cleaned, the profile of the original substrate can be restored. 

G. SPONGE JETTING. 

1. Sponge jetting involves the use of specialized blasting equipment that propels a 

combination of an abrasive material (e.g., steel, garnet) encased in a soft sponge 

(foam) medium. The high-density foam cleaning medium is absorptive and can be used 

either wet or dry. When the sponge is dampened, it can help reduce the amount of dust 

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generated without unduly wetting the surface. The medium provides the impact needed 

to break the paint coating up into larger particles, and particle rebound is low because 

of the energy absorbed by the foam. 

2. The relatively small volume of dust generated by this method can help to reduce 

containment requirements, although some screens and tarping are necessary to isolate 

the work area and to allow the sponge and debris to be collected. Productivity is lower 

than for open abrasive blasting using more traditional abrasives, according to 

contractors who have used this product (CONSAD 1993). 

H. CARBON-DIOXIDE (DRY-ICE) BLASTING. 

1. Cryogenic cleaning by blasting with dry-ice pellets is one of the least-tried methods of 

surface preparation (Figure V:3-2). A stream of pellets cooled to about -100° F (-79° C) 

moves at high velocity through a blast hose and nozzle. The pellets impinge on the 

surface and then sublime, leaving only paint debris to be cleaned up. The greatest 

advantage to carbon-dioxide (dry-ice) blasting is that the blast medium sublimes and 

needs no further handling or disposal. However, when used in confined spaces, the 

potential for creating an oxygen-deficient environment is significant and must always be 

guarded against. FIGURE V:3-2. DRY-ICE BLAST CLEANING.

 

2. The cost of cryogenic cleaning, however, is still often prohibitive. In addition, the 

production rate with dry-ice blasting is sometimes slow compared with the rate for 

conventional abrasive blasting. Finally, because only the paint is removed, the surface 

may need to be "brush-off" blasted with an abrasive to produce a rough surface to 

facilitate adhesion of the new coating. 

I. WELDING, BURNING, AND TORCH CUTTING. 

1. Welding and cutting activities that potentially involve exposure to lead can occur as part 

of a number of construction projects such as highway/railroad bridge rehabilitation 

(including elevated mass-transit lines), demolition, and indoor and outdoor industrial 

facility maintenance and renovation. Lead exposures are generated when a piece of 

lead-based painted steel is heated to its melting point either by an oxyacetylene torch 

or an arc welder. In this situation, lead becomes airborne as a volatilized component of 

the coating. 

2. The amount of time a worker may spend actually welding or cutting can vary from only 

a few minutes up to a full shift. In addition, the coating being worked on may consist of 

several layers of lead-based paint, each of which could contain as much as 50% lead. 

Taken together, these factors suggest that a worker's exposure to airborne lead during 

welding or cutting activities can vary widely and may be exceedingly high. Lead 

burning, a process by which virgin or alloyed lead is melted with a torch or otherwise 

fused to another lead object, is typically performed in maintenance operations on 

electrostatic precipitators or during the installation of lead shot, bricks, or sheets in the 

walls or floors of health-care x-ray units or industrial sites. Lead health hazards in this 

operation, as in welding and torch cutting, are from lead that is superheated and 

released into the worker's breathing zone in the form of a fume. 

3. Engineering Controls. The engineering controls that can be used, depending on 

feasibility, are: 

a. Local exhaust ventilation (LEV) that has a flanged hood and is equipped with HEPA 

filtration may be appropriate where the use of LEV does not create safety hazards. Use 

of a flexible duct system requires that the welder be instructed to keep the duct close to 

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the emission source and to ensure the duct is not twisted or bent. 

b. A fume-extractor gun that removes fumes from the point of generation (Figure 

V:3-3) is an alternative to an exhaust hood for gas-shielded arc-welding processes. 

Such extraction systems can reduce breathing zone concentrations by 70% or more 

(Hughes and Amendola, 1982). These systems require that the gun and shielding gas 

flow rates be carefully balanced to maintain weld quality and still provide good exhaust 

flow. FIGURE V:3-3. FUME-EXTRACTOR GUN.

 

c. A longer cutting torch can be used in some situations to increase the distance from 

the lead source to the worker's breathing zone. 

d. Hydraulic shears can sometimes be used to mechanically cut steel that is coated 

with lead based-paint. The use of this method is limited by the ability of the shears to 

reach the cutting area. 

e. Whenever possible, pneumatic air tools should be used to remove rivets in lieu of 

burning and torch cutting. 

4. Work Practice Controls. The following work practice controls will help to reduce 

worker exposures to lead during welding, burning, and torch cutting: 

a. Strip back all lead-based paint for a distance of at least 4 inches in all directions from

the area of heat application. Chemical stripping, vacuum-shrouded hand tools, vacuum 

blasting, or other suitable method may be used. However, in enclosed spaces, strip 

back or protect the workers with air-line respirators in accordance with the 

requirements of 29 CFR 1926.354(c). 

b. Ensure that workers avoid the smoke plume by standing to the side or upwind of the 

cutting torch whenever the configuration of the job permits. 

c. Prohibit burning to remove lead-based paint. Paint should be removed using other 

methods, such as chemical stripping, power tools (e.g. needle guns) with vacuum 

attachments, etc. 

J. SPRAY PAINTING WITH LEAD-BASED PAINT. 

1. In the construction field, the primary source of lead exposure in painting is red lead 

primers, although many finish coatings continue to contain a small percentage of lead. 

For most interior or exterior construction painting projects, workers employ 

conventional compressed-air spray equipment. Overspray and rebound of the paint 

spray off the structure being painted increase the inhalation hazards to workers using 

lead-based paint. The magnitude of the painter's particulate exposure to lead is 

dependent on the product used, its lead content, and the quantity of paint applied. 

2. Engineering Controls. The following engineering controls will reduce or eliminate 

worker exposures to lead during painting: 

a. Applying non-lead containing paints and primers. 

b. To the extent possible, replacing lead chromate with zinc. 

c. Hand-applying lead-based paint by brush or roller coating methods rather than spray 

methods. 

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d. Using local exhaust ventilation with proper filtration. (The ability to use LEV may be 

limited by the location of the painting operation.) 

K. MANUAL SCRAPING AND SANDING OF LEAD-BASED PAINTS. 

1. Hand scraping of lead-based paints involves the use of a hand-held scraping tool to 

remove paint from coated surfaces. The health hazards in this activity are caused by the 

lead dust and paint chips produced in the scraping process. Hand sanding can also 

produce excessive dust. These activities are typically performed during residential and 

commercial/institutional lead abatement projects. 

2. Engineering and Work Practice Controls. Controls that employers can implement 

to protect workers performing scraping and sanding of lead-based paints are: 

a. Use of wet-sanding and wet-scraping methods in conjunction with HEPA vacuuming 

or HEPA mechanical ventilation. Wet methods include misting of peeling paint with 

water before scraping, and sanding and misting of debris prior to sweeping or 

vacuuming. 

b. Use of shrouded power tools with HEPA vacuum attachments. The shroud must be 

kept flush with the surface. 

c. Use of techniques with known low exposure potential, such as encapsulation and 

removal or replacement instead of hand-scraping and hand-sanding. 

L. MANUAL DEMOLITION AND/OR REMOVAL OF PLASTER WALLS OR BUILDING 

COMPONENTS. 

1. The demolition of lead-painted plaster walls or building components is usually 

performed by striking a wall with a sledge hammer or similar tool. This results in an 

uncontrolled release of dust. High levels of airborne total dust and lead dust can be 

generated by breaking lead-painted plaster into small pieces. 

2. Removal and replacement is the process of removing components (such as windows, 

doors, kitchen cabinets, and trim) that have lead-painted surfaces and installing new 

components that are free of lead-containing paint. Exposures may result from the 

release of dust and paint-chip particles when these items are removed with a prybar or 

cut with a saw. Unless the component is seriously deteriorated, occupational exposures 

during this operation are minimal. 

3. Engineering and Work Practice Controls. Controls and practices used to reduce 

lead exposures during demolition/removal of architectural components are: 

a. Install partitions or other temporary barriers to allow for partial containment of dust 

to minimize exposures to other workers and building occupants. 

b. Keep surfaces and debris moist when disturbing them. 

c. Remove wallboard by cutting it into large pieces/sections with a carpet knife or 

shrouded saw with HEPA vacuum attachment. 

M. HEAT-GUN REMOVAL OF LEAD-BASED PAINT. 

1. In this activity, the worker uses a heat gun, a tool similar in design to a hand-held hair 

dryer. The heat gun produces a stream of hot air that the worker directs to heat the 

lead-based paint. This heat separates the substrate, which is subsequently scraped off 

with a putty knife or similar tool. The health hazards encountered are generated by lead 

fumes released into the air during the heating process and lead particulates created 

during the scraping process. 

2. Engineering and Work Practice Controls. The controls used to reduce lead 

exposure during heat gun operations are: 

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a. Provide thermostatic control for heat guns to restrict operating temperatures to the 

lowest temperature that will allow for the effective removal of lead-based paint. 

[NOTE: HUD places a 700° F limit on the use of heat guns. However, NIOSH (1990) 

reports that the 700° F restriction for heat-gun nozzle airstream temperatures appears 

to limit the effectiveness of the guns in removing paint. To compensate for the 

airstream temperature limitation, workers often hold the gun nozzle close to the 

surfaces (less than one inch). This reduces the surface area heated and potentially 

increases the time required for paint removal and prolongs the duration of exposure. On 

the other hand, commercial heat guns operating at airstream temperatures of 1,000° F 

can generate and disperse high levels of airborne lead.] 

b. Use techniques with known low exposure potential such as encapsulation and 

removal/replacement instead of hand scraping with a heat gun. 

N. CHEMICAL STRIPPING OF LEAD-BASED PAINT. 

1. Chemical stripping of old paint coatings is performed by applying solvent- or 

caustic-based strippers to the surface, either by hand or spray gun. The product 

remains on the surface for a period ranging from five minutes to 48 hours, depending 

on the thickness and composition of the paint being removed. Mechanical scrapers, a 

vacuum system, or pressurized water are then used to remove the product and the 

stripped paint. Finally, a wet-vac system is used to clean the surface, although 

hard-to-reach areas may not be accessible to the vacuum. This system may employ 

vibrating brushes to help release the paint from the surface. 

2. Some chemical stripping products are toxic (e.g. methylene chloride) when inhaled or 

absorbed through the skin, and many are skin irritants or skin corrosives. Consequently, 

appropriate controls must be implemented when using chemical strippers. Although 

OSHA does not prohibit the use of methylene chloride-based stripping products, some 

local, State, and other Federal authorities may prohibit its use in residential units. 

3. In the industrial arena, some disadvantages of chemical stripping are that containment 

and collection of the waste materials may be difficult and productivity may be low 

compared with the rate for conventional abrasive blasting. Because chemical stripping 

removes only the paint, a final abrasive blast must often be performed to remove rust 

and mill scale and to provide the metal profile required for adhesion of the new paint. 

Because residues of primer may still adhere to the substrate at the time of the final 

blast, the potential for exposure to lead continues, although at greatly reduced levels. 

O. ENCAPSULATION OF LEAD-BASED PAINT. 

1. Encapsulation refers to processes that makes lead paint inaccessible by covering or 

sealing the lead-painted surfaces. This may be achieved by installing sheet-rock walls 

on top of the paint, covering surfaces with fiberglass, or recoating housing components 

with a nonlead-based paint. Encapsulation is the best strategy if it provides relatively 

long term protection and does not require routine maintenance to ensure the integrity 

of the encapsulant. Local, State, and other Federal authorities may have specific 

requirements regarding types of encapsulants that can be used. 

2. If surfaces are peeling or deteriorating and scraping is necessary prior to encapsulation, 

this method will produce lead dust and paint chips. If encapsulation is used over a 

surface covered with intact paint, little dust is generated and cleanup and waste 

disposal problems are therefore minimized. 

3. Encapsulation may be a temporary measure because the lead-based paint that remains 

under the encapsulant may have to be disturbed at a future time and create a new 

potential for lead exposure. Encapsulation is particularly attractive as a control method 

when large surfaces such as walls, ceilings, and floors are involved because 

encapsulation requires little containment or cleanup and does not threaten the 

environment. Documentation of encapsulation is important because of the potential for 

exposures to underlying lead-based paint during maintenance, future renovation, and 

eventual demolition. 

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4. Engineering Controls. During encapsulation operations, engineering controls may not 

be necessary to protect workers from lead exposures. Results from HUD air sampling 

(NIOSH 1990) indicate that 8-hour TWA exposures are well below 50 mg/m3 for this 

activity. 

P. POWER-TOOL CLEANING. Power-tool cleaning involves the use of power-operated impact, 

grinding, or brushing tools. Power tools available for paint removal include needle guns, disc 

sanders, grinders, power wire brushes, rotary hammers, rotary peeners, and scarifiers. Each 

can be used with or without a local exhaust ventilation control. Health hazards in this operation 

come from lead dust and paint chips created during tool use. 

1. Engineering and Work Practice Controls. The following controls and practices are 

recommended to reduce worker exposures to lead during power-tool cleaning of leadpainted surfaces. 

a. Use shrouded tools wherever feasible (shrouding can restrict accessibility to the 

work area) with vacuum attachment to collect dust and debris at the point of 

generation (Figure V:3-4). Exhaust ventilation must be equipped with an appropriate 

HEPA filtration/collection system. FIGURE V:3-4. EXAMPLE 

OF A SHROUDED TOOL. 

 

b. Keep shroud flush with the surface during cleaning. Dust generation is minimal, but 

dust can escape when cleaning areas are of difficult configuration because it may not 

be possible to maintain a seal between the tool and the surface in these areas. 

Q. USE OF LEAD POTS. This activity involves the use of a lead pot to melt lead for use in (1) 

cast-iron soil pipe installation, removal, and servicing, (2) electrical cable splicing, and (3) 

babbitting while recabling. The health hazard in these operations arises from lead fumes 

becoming airborne. These operations are discussed below. 

1. Cast-Iron Soil Pipe Installation and Removal. 

a. Lead caulking is used in commercial construction building applications, most 

commonly in the joining or sealing of cast iron soil pipes. The lead used for this purpose 

must be liquefied. The process of heating the lead and applying it as a liquid presents 

an opportunity for exposure to lead-oxide fumes. The primary exposure to fumes occurs 

while dipping the ladle into the lead pot, carrying the ladle by hand to the solder area, 

and pouring solder into the pipe joint. Pot dressing is another source of lead fumes. 

Additional exposures to lead fumes can occur during repair and maintenance operations 

in which pipe joints are heated to melt the lead caulking and are then pulled apart. 

b. Engineering Controls. The controls used with lead pots include a portable local 

exhaust ventilation system mounted directly on or near the pot to control lead fumes, or 

a thermostatic control device installed on the lead pot to prevent overheating to reduce 

the amount of lead fumes generated. 

c. Work Practice Controls. During the repair and removal of cast iron pipes, workers 

can disconnect the pipe by cutting it (above and below the leaded joints) without 

creating a lead exposure problem. 

2. Electrical Cable Splicing. 

a. The cable splicing performed by electrical utility workers and utility contractors is 

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another example of the use of lead pots. In this operation, the lead is typically melted 

above ground and then lowered by the assistant to the splicer, who is located in the 

manhole or underground vault. The splicer pours the lead from one ladle over the 

copper joint and catches the excess in another ladle held below. This process is 

repeated several times until the metal is too cold to pour. A lead metal sheath is then 

slipped over the connection and the ends are sealed with molten lead. 

b. Engineering Controls. During cable splicing, the following engineering controls are 

used: (1) a portable local exhaust ventilation system is mounted directly on or near the 

lead pot; (2) a thermostatic control device can be installed on the lead pot to prevent 

overheating and reduce the amount of lead fumes; and (3) rubber or plastic connectors 

can be used instead of molten lead as the sealing method (NIOSH 1993b). 

3. Babbitting While Recabling. 

a. Elevators receive new wire ropes (i.e., cables) every 10 to 15 years on average. 

When recabling elevator ropes, it is necessary to secure the ends of the wire ropes in 

the baskets of thimble rods (sockets) at each end of the cable to keep the multi strand 

cable from unwinding. This is accomplished by pouring a tin-based babbitt material into 

the sockets to keep all of the strands in place within the socket. 

b. Engineering Controls. The tin-based babbitt material is usually melted in a 

thermostatically controlled pot that keeps the lead at a temperature below that at which 

it fumes. This job is done within the confines of the hoist way, which normally has an 

updraft that will draw lead fumes up through the hoist way and away from the worker 

and release the fumes over the roof of the building. 

c. Where legally permitted, some elevator companies have switched the wire ropes on 

older elevators from sockets that utilize poured babbitt metal to wedge clamps or to 

sockets utilizing a thermoplastic/epoxy mixture (Personal communication, E. Donoghue, 

Consultant to National Elevator Industry, Inc., February 25, 1991.) 

R. SOLDERING AND BRAZING. 

1. Soldering and brazing are techniques that are used to join metal pieces or parts. These 

techniques use heat in the form of a propane, MAPP gas, or oxyacetylene flame and a 

filler metal (tin/lead compositions, rosin core, brazing rods) to accomplish the task of 

joining. This activity is usually performed by workers in the plumbing trades. The 

potential exposure source is the filler metal that contains lead. 

2. Soldering and brazing operations present similar health hazards (airborne lead fumes) 

but to a different degree. Most soldering operations occur at temperatures that are less 

than 800°F. The melting point of the filler metals is usually quite low (<600°F) and the 

activity does not generate significant concentrations of metal fumes. Brazing operations 

usually occur at temperatures in excess of 800°F. The temperature of the operation is 

of major importance because temperature determines the vapor pressure of the metals 

that are heated and therefore the potential concentration of metal fumes to which the 

employee may be exposed. 

3. Because most field soldering and brazing work is conducted with a torch, it is difficult to 

regulate operating temperatures to within recommended limits to reduce the amount of 

metal fumes generated. However, worker 8-hour TWA exposures to metal fumes are 

usually low due to the limited durations of exposure associated with soldering and 

brazing work. Electricians soldering electrical connections, plumbers soldering 

nonpotable water lines, or roofers repairing tin flashing could all experience these 

short-term and intermittent lead exposures. 

4. Engineering Controls. In confined areas, portable local exhaust ventilation can be 

used to remove metal fumes and gases associated with this type of work. 

S. USE OF LEAD-CONTAINING MORTAR IN CHEMICAL (ACID) STORAGE AND PROCESS 

TANKS. 

1. High-pressure acid tanks used in the mining industry (especially during gold refining), 

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as well as tanks (called "accumulators") found in some older paper mills and perhaps in 

other industries, are often lined with a specialized tile or lead brick. This brick or tile is 

held in place with a specialized lead-containing mortar or grout. Every three to five 

years the linings of these tanks must be repointed (i.e. the grout between the tiles/brick 

must be restored), repaired, or relined with an entirely new lining (either tile or lead 

brick). Speciality contractors are hired to do this work. 

2. After inspection of the lining, the damaged pointing (i.e. mortar between the tiles/brick) 

must be removed. This is done by a crew of workers simultaneously chipping away the 

old mortar by hand. After the old mortar has been removed, new lead-containing 

mortar (which is high in lead oxide content) is mixed in small batches to prevent its 

drying out before use. This mortar is then used as pointing between the tiles or bricks. 

Lead must be included in the grout to ensure the structural integrity of the tank, i.e., 

lead is one of the few materials that can withstand the corrosive effects of the acids in 

use. The health hazards in these operations arise from lead dust and particulates, with 

a potential for high airborne levels in the mortar mixing area. 

3. The following engineering controls apply: 

a. Portable local exhaust ventilation should be used to remove lead dust and 

particulates from localized areas. 

b. The tank should be kept under negative pressure to remove the dust from the tank 

whenever workers are inside. All exhaust systems and vacuum equipment must be 

equipped with HEPA filters. 

T. HANDLING LEAD SHOT, BRICKS, OR SHEETS, AND LEAD-FOIL PANELS. 

1. Due to its inherent properties, lead is used extensively for shielding from radiation 

sources. The three principal projects involving the handling of lead shot, bricks, or 

sheets and lead-foil panels include the construction of linear accelerator suites, 

radiology (x-ray) suites, and industrial processing tanks. Installation and cutting of solid 

lead sheets, lead foil panels, and lead brick as well as the pouring of lead shot into 

cavities produce lead dust in varying quantities (Personal communication, G. Hyde, 

Baltimore Lead Burning Corporation, March 5, 1991). Additional exposures to lead can 

occur when lead sheets and bricks are fused with a welding torch or cut with a power 

saw when they are made into shielding containers. 

2. Engineering Controls. Portable local exhaust ventilation should be used for lead 

burning (melting/fusing) and sawing operations involving lead sheets and lead bricks, 

where exposures can easily exceed the PEL. Engineering controls may not be necessary 

to protect workers from lead exposure when pouring lead shot into cavities or when 

cutting lead-foil sheets. 

U. REINSULATION OVER EXISTING MINERAL WOOL. 

1. Mineral wool insulation manufactured before about 1970 has been found to have lead 

particles. According to industry sources, lead slag is no longer used in the manufacture 

of mineral wool, although lead can be present as a trace impurity (CONSAD 1993). 

2. Exposures to lead while installing new insulation over mineral wool put into place before 

1970 will vary markedly from job site to job site because of such factors as the size of 

the space, the method of application, and the amount of lead dust in the mineral wool. 

Workers perform this work in relatively confined areas (such as an attic) or in an open 

bay structure. Moreover, the worker can install insulation manually (e.g., when installing 

rigid preformed insulation around pipes) or mechanically using, for example, a 

pneumatic blower (e.g., when blowing fiberglass or mineral wool into place over 

existing mineral-wool insulation). Exposures are likely to be highest when insulation is 

blown into place in a confined space. The lead health hazard during these operations 

comes from lead particulates released into the air. 

3. Engineering Controls. No feasible engineering controls are known to exist for this 

operation. 

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V. REMOVAL AND REPAIR OF STAINED-GLASS WINDOWS. 

1. The removal and repair of stained-glass windows includes several distinct activities: 

 Removing the glass from the building and tracing the location of the pieces of 

glass; 

 Disassembling the lead strips ("came") and removing the lead putty seals; 

 Cleaning or replacing of the individual pieces of glass; and 

 Reassembling and soldering the "came." 

2. Only the first activity, removal, takes place at the construction site. Health hazards arise 

from lead dust released into the air during glass removal. The other activities typically 

take place in a workshop and are therefore covered under the general industry lead 

standard (29 CFR 1910.1025). 

3. Engineering and Work Practice Controls. The control that applies is precleaning 

the stained-glass window with HEPA vacuums or damp wiping to remove loose dust 

before removal could lower exposures during removal. Whenever feasible, use portable 

local exhaust ventilation. 

W. INDUSTRIAL VACUUMING. 

1. Industrial vacuuming involves the use of vehicle-mounted vacuum systems to clean 

various areas of industrial facilities. The companies providing this industrial cleaning 

service are hired to clean such areas as catwalks, structural beams, and floors to reduce 

worker exposure to accumulated dust and debris that results from normal operations. 

The kinds of facilities where vacuuming could result in lead exposure include nonferrous 

metal plants (excluding aluminum) or steel plants melting lead-containing scrap in an 

electric-arc furnace. 

2. Engineering and Work Practice Controls. Conventional cartridge dust collection 

systems capable of meeting the EPA ambient air quality requirements of 1.5 μg/m3 for 

discharge air should be used. 

X. MISCELLANEOUS ACTIVITIES. The workers included in this group are those who are 

secondarily involved with other activities described above. These workers are not directly 

involved in the lead-generating activity but may nonetheless be exposed to lead in the course 

of their work. The lead exposure of this group of workers can be caused either by the activities 

of their co-workers or their own work-related activities. 

Three separate miscellaneous activities representative of the jobs performed by this group of 

workers are discussed below. These categories are enclosure movement, activities related to 

abrasive blasting and repainting, and activities related to lead abatement. 

1. Enclosure Movement. 

a. Moving containment enclosures involves the setting up, tearing down, and handling 

of flexible nylon, plastic, and cotton tarpaulins as well as framing members which 

together form the sides of the enclosure. Projects such as the abrasive blasting of 

bridges, elevated highways, water towers, and storage tanks are likely to involve some 

type of containment structure. 

b. Generally, the sequence of events in setting up, tearing down, and moving of a 

containment structure on a bridge project is as follows: First, a section of the bridge is 

blast-cleaned and primed within the enclosure. After completion, the sides of the 

containment (tarpaulins and framing) are dismantled so that the structure can be 

moved forward to the next section of the bridge to be worked on. After relocating the 

containment structure, the framing and plastic nylon coverings for the sides are 

reinstalled before blasting and repainting operations begin. As the enclosures are torn 

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down and moved, the workers involved are exposed to lead dust generated by the 

movement of the containment components. 

c. Engineering and Work Practice Controls. The inside of the containment should 

be cleaned prior to tear-down and movement to remove the lead-contaminated dust 

that accumulates on the walls and ledges. If compressed air is used to clean, the 

ventilation system of the containment structure must be operating and workers must 

wear appropriate respirators. 

2. Abrasive Blasting and Repainting Activities. 

a. In addition to those workers actually performing the abrasive blasting, other workers 

perform support activities such as pot-tending, operating the recycling and 

vacuum-truck equipment, and tending the abrasive medium transfer and waste-removal 

equipment. These workers may be exposed to lead as a result of the dispersion of lead 

dust from the abrasive blasting, the leaking of hose connections, the changing of waste 

drums, the malfunctioning of recycling equipment, and clean-up activities. 

b. Engineering Controls. Full containment enclosures provided with exhaust 

ventilation and conventional cartridge filtration units should be used to reduce lead-dust 

emissions from the abrasive blasting area and prevent environmental contamination. In 

addition, small HEPA-filtered vacuum systems should be used to clean lead dust from 

work clothing and to clean up small spills. 

c. Work Practice Controls. Controls involve regular inspections and timely 

maintenance of process equipment and control equipment help to eliminate dust leaks 

and prevent equipment malfunction or failure. 

Y. LEAD ABATEMENT ACTIVITIES (COMMERCIAL/INSTITUTIONAL AND 

RESIDENTIAL). 

1. These miscellaneous activities occur in conjunction with lead abatement or in-place 

management activities that have been previously addressed (i.e. dry hand-scraping, 

removal, and replacement of building components, heat-gun removal, chemical 

stripping of lead-based paint, and encapsulation). These ancillary activities include 

washing, HEPA vacuuming, enclosure set-up and tear-down, and waste disposal. 

2. Engineering Controls. Exposure levels are generally below the PEL during the 

performance of these activities, and engineering controls are therefore not likely to be 

necessary. 

3. Work Practice Controls. Surfaces and debris should be kept moist when they are 

being disturbed. Before sweeping or vacuuming, dust and debris should be misted with 

water to reduce airborne dust. Plastic sheeting should also be misted with water before 

handling to reduce dust. 

4. All retained liquid waste should be poured through a filter cloth to remove paint chips 

and other debris prior to disposal. Filtered materials as well as other waste and debris 

should be placed in appropriately labeled, 6-mil plastic bags or sealed containers 

suitable for the transport of lead waste, and stored in a secure area pending disposal in 

accordance with State and/or local requirements. 

IV. BIBLIOGRAPHY. 

CONSAD Research Corporation. 1993. Economic Analysis of OSHA's Interim Final Standard for Lead in 

Construction. Performed under contract to the Office of Regulatory Analysis, OSHA. Contract No. 

J-9-F-1-0011. 

Hughes, R.T., and Amendola, A.A. 1982. Recirculating Exhaust Air. Plant Engineering, March issue. 

Knoy, T. 1990. Vacuum Blasting of an Elevated Water Storage Tank. Steel Structures Painting Council, Lead 

Paint Removal From Industrial Structures: Meeting the Challenge, SSPC 90-01-:95-99. 

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NIOSH. 1993a. Notice to All Users of Type CE, Abrasive-Blast Supplied-Air Respirators. NIOSH Division of 

Safety Research. 

NIOSH. 1993b. Health Hazard Evaluation Report. Boston Edison Company. DHHS NIOSH Publication HETA 

90-075. 

NIOSH. 1992. NIOSH Alert: Request for Assistance in Preventing Lead Poisoning in Construction Workers.

DHHS, April 1992. 

NIOSH. 1990. Health Hazard Evaluation Report. HUD Lead-Based Paint Abatement Demonstration Project. 

DHHS NIOSH Publication HETA 90-070-2181. 

Waagbo, S. and McPhee, W. 1991. Vacuum Blasting Lead-Based Paint Structures. Steel Structures Painting 

Council, Lead Paint Removal: Meeting the Challenge, SSPC 91-05:117-130. 

APPENDIX V: 3-1. LEAD-RELATED CONSTRUCTION TASKS AND THEIR PRESUMED 8-HOUR TWA 

EXPOSURE LEVELS. 

The current OSHA lead standard for construction (29 CFR 1926.62) is unique in that it groups tasks 

presumed to create employee exposures above the PEL of 50 μg/m3 as an 8-hour TWA. Until the employer 

performs an employee exposure assessment and determines actual employee exposure, the employer must 

assume that employees performing one of these tasks are exposed to the levels of lead indicated for that 

task in this Appendix. For all three groups of tasks, employers are required to provide respiratory protection 

appropriate to the task's presumed exposure level, protective work clothing and equipment, change areas, 

hand-washing facilities, training, and initial medical surveillance as prescribed by paragraph (d)(2)(v) of the 

standard. The only difference in the provisions applying to these groups is in the degree of respiratory 

protection required. 

> 50 to 500 μg/m3 > 500 μg/m3 to 2,500 μg/m3 > 2,500 μg/m3

Manual demolition Using lead-containing mortar Abrasive blasting

Dry manual scraping Lead burning Welding

Dry manual sanding Rivet busting Torch cutting

Heat gun use Power tool cleaning without dust 

collection systems 

Torch burning

Power tool cleaning with dust 

collection systems

Cleanup of dry expendable abrasive 

blasting jobs

Spray painting with lead paint Abrasive blasting enclosure movement 

and removal

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