Regulations (Preambles to Final Rules) - Table of Contents Regulations (Preambles to Final Rules) - Table of Contents
• Record Type: Occupational Exposure to 4,4' Methylenedianiline (MDA)
• Section: 10
• Title: Section 10 - X. Summary and Explanation of the Standard for the Construction Industry

X. Summary and Explanation of the Standard for the Construction Industry

Paragraph (a). Scope and Application

A separate standard for occupational exposure to MDA in the construction industry was developed. OSHA took this action based primarily on the recommendations of the MDA Mediated Rulemaking Committee which recommended that a separate standard be developed for the construction industry. OSHA also consulted, as required by section 107 (e) of the Contract Work Hours and Safety Standards Act (40 U.S.C. 333 (e)) and 29 CFR 1912.3, with the Construction Advisory Committee concerning this rule for Construction. This meeting took place on November 3, 1987. This Committee advised that OSHA adopt the recommendations made by the MDA Mediated Rulemaking Advisory Committee for the construction industry and use such as the basis for its standard for construction. The Committee made this recommendation because they felt that the specialized use of MDA in the construction sector could best be addressed through the development of a separate construction standard. OSHA agreed with the recommendations of both committees and has developed a separate standard for the construction industry.

The final standard uses 1910.12 (b) to define "construction work" as work for construction, alteration, and/or repair, including painting and decorating. Accordingly, the final standard applies to all occupational exposures to MDA in the construction industry. Depending on the nature and extent of exposure, certain provisions of the standard rule may not be applicable in certain situations or may have limited applicability. The applicability of many provisions of the standard is based on the results of initial employee monitoring conducted by the employer or on the availability of other objective data concerning employee exposures or product characteristics. The construction operations listed in paragraph (a)(1) include construction, alteration, repair, maintenance, or renovation of structures, substrates, or portions thereof that contain MDA; the installation or finishing of surfaces with MDA containing products; the removal of MDA spills or emergency clean-up on site; and transportation, disposal, or storage of contaminated products.

MDA spill and emergency situations are included within the scope of the standard, because these events clearly have the potential for serious employee and bystander exposures. MDA spills might occur during the handling of bags or containers of MDA-containing materials to be used at the construction site. The final group of activities listed in the scope and application paragraph includes the transportation, disposal, storage, or containment of MDA or MDA-containing products on the worksites at which construction operations occur. These operations are included because they have considerable potential for excessive employee exposure to MDA, and, if not closely supervised and properly conducted, may lead to serious bystander exposure as well. The Environmental Protection Agency (EPA) has specific requirements for the disposal of hazardous waste, and the MDA standard contemplates compliance with EPA provisions for the safe disposal and handling of MDA-containing wastes and of MDA-contaminated clothing.

The final standard has been carefully structured to relate the stringency of the requirements to the extent and duration of employee exposures. OSHA therefore believes that a compliance burden will not be placed on construction employers who either do not use, handle, or apply MDA-containing products or who maintain MDA exposures in their workplaces at levels below the action level or where dermal exposure to MDA does not exist. In addition, the exemptions found in paragraphs (a)(2) through (a)(6) are identical to exemptions found in the general industry standard. Full discussions regarding the rationale for these exemptions can be found in the general industry preamble and apply equally well here. Essentially, these exemptions apply to workplaces where MDA is present but in such a way as to not present a significant risk of harm to the employee.

Paragraph (b). Definitions

Paragraph (b) of the MDA standard for the construction industry defines a number of terms used in the standard. In some instances, the definitions used are consistent with those of other OSHA standards to be used in the general industry standard, e.g., "Director," "Assistant Secretary," and "Authorized person." However, certain other terms require definition because they are used in accordance with their meanings in the construction industry.

Action level is defined as one-half of the PEL. If employers are engaged in MDA work causing worksite levels of MDA above the action level for 30 or more days per year, they must also institute a medical surveillance program for all employees. In addition, on sites where food and beverages are consumed and the airborne MDA level exceeds the PEL, the standard requires employers to provide lunch areas that have airborne MDA levels below the action level.

Definition of MDA The final construction standard includes a definition of MDA. Included in the definition are the salts of MDA. The rationale for including the salts in the definition of MDA was not challenged in the response to the NPRM. Thus the compounds covered by the proposed definition remains the same in the final standard.

The NPRM definition contained an exclusion for finished products which is now part of the scope and application section of this final rule.

Employee exposure is defined as that exposure to airborne MDA that would occur if the employee were not using respiratory protective equipment or personal protective clothing or equipment. OSHA believes it is essential to determine employee exposure levels without the use of respiratory protection in order to gauge the efficacy of mandated work practice and engineering controls.

Decontamination area is defined as an area outside of but as near as practical to the regulated area, consisting of an equipment storage area, wash area, and clean change area, which is used for the decontamination of workers, materials, and equipment contaminated with MDA. For more discussion see the hygiene facility section.

Dermal exposure to MDA occurs where employees are engaged in the handling, application or use of mixtures or materials containing MDA, with any of the following non-airborne forms of MDA: (i) liquid, powdered, granular, or flaked mixtures containing MDA in concentrations greater than 0.1 percent by weight or volume; and (ii) materials other than "finished articles" containing MDA in concentrations greater than 0.1 percent by weight or volume. The final standard requires the employer to take certain protective actions where employees, engaged in the handling application or use of mixtures or materials containing MDA, are subject to dermal exposure to MDA. In situations where employees handle, apply or use any MDA mixtures or materials as defined above, dermal exposure to MDA is considered to occur. The agency believes that correlating dermal exposure with the handling, applying or using specific forms of MDA removes the confusion that has arisen from using such terms as "likelihood of dermal exposure." Simply put, dermal exposure to MDA is assumed to occur when employees handle, apply or use any MDA falling under the definition of "Dermal exposure to MDA."

Historical monitoring data is defined as monitoring data for construction jobs that are substantially similar. The data must be scientifically sound, the characteristics of the MDA containing material must be similar and the environmental conditions comparable. See the monitoring discussion below and the Committee discussion at 52 FR 26868.

Regulated areas are defined as areas where MDA concentrations exceed or can be reasonably expected to exceed the permissible exposure limits or where employees are engaged in the handling, application, or use of MDA that can result in "dermal exposure to MDA."

Paragraph (c). Permissible Exposure Limit

The final standard requires that the PEL for the construction industry be set at 10 parts of MDA per billion parts of air as an 8-hour time-weighted average (TWA) limit and at 100 ppb as a short term exposure limit (STEL). This is consistent with the final standard for general industry. The requirements contained in the final standard are supported by OSHA's findings that occupational exposure to MDA under current occupational conditions poses a significant risk to the health of employees and that the final standard can achieve a reduction in that risk.

As with the final standard for general industry, the standard for construction establishes a ceiling or short-term exposure limit of 100 ppb (sampled over a 15-minute period) for MDA.

Biological monitoring was also recommended by many of the hearing participants for inclusion into the construction standard. OSHA's rationale for not including biological monitoring provisions in the construction standard are the same reasons stated in the general industry standard.

Paragraph (d). Communication Among Employers

Paragraph (d) of the rule requires that, on multi-employer construction worksites, employers performing MDA work requiring the establishment of a regulated area inform other employers on the site of the nature of their work with MDA and of the existence of and requirements pertaining to regulated areas. OSHA recognizes that several different operations involving workers from numerous trades may simultaneously take place on the same construction site and that the exposures of these workers to MDA should be minimized to the extent possible. OSHA believes that requiring employers who are directly involved in MDA-related activities to inform other employers working nearby on a multi-employer worksite of the existence of hazardous levels of MDA, regulated areas, and the rules pertaining to such areas will contribute substantially to the protection of these nearby employees.

Paragraph (e). Emergency Situations

OSHA believes that available health data suggest that elevated short-term exposure to MDA should be viewed with concern. An unexpected high exposure must be viewed as an emergency situation. A written plan is required for each construction operation where there is a possibility of an emergency. The plan shall include the applicable elements prescribed in 29 CFR 1910.38, "Employee emergency plans and fire prevention plans." OSHA believes that there is no substitute for proper planning for an emergency situation. In the construction industry where the work force and the job sites are constantly changing, the importance of proper emergency planning can not be overstated.

The standard provisions also include a requirement to alert employees other than those who have the potential to be directly exposed in an emergency situation. Such employees may be employees from neighboring work sites who may inadvertently approach the emergency site. They may also include employees of other employers or from other work shifts or employees who may be later exposed to work surfaces or equipment contaminated as a result of the emergency.

OSHA believes that the performance language of the emergency situation paragraph will give employers the flexibility to choose any effective method of alerting employees, including communications systems, voice communication, or a bell or other alarm.

There was considerable testimony provided regarding the difficulty with implementing the proposed emergency requirements for the construction industry. The major difficulty was with the written plan which was proposed at 54 FR 20730 as follows:

(1) Written plan. (i) A written plan for emergency situations shall be developed for each workplace where there is a possibility of an emergency. Appropriate portions of the plan shall be implemented in the event of an emergency. (Emphasis added.)

The Dow Chemical Company (Ex. 11-20) states that the requirement that a written emergency plan be developed for each construction worksite is infeasible for jobs of short duration. They recommend that OSHA establish a generic emergency plan approach. The Society of the Plastics Industry, Inc. (Ex. 11-16) agrees that it is not feasible to have a specific emergency plan for every work site. Specifically, they state:

Such a requirement is not practical for all worksites of the construction industry. For example, a work crew may apply epoxy floor coverings containing MDA to three or four different worksites in a single day. To develop a written emergency plan for each of these sites could require more time than is necessary to carry out the work. (page 3).

SPI believes that construction employers who have MDA related jobs of short duration should be permitted to develop a written emergency plan that covers emergency situations, typical of a work operation, rather than a particular site. For example, instruction to don respirators in certain described situations, to locate the nearest exit upon arrival at each worksite, and to use that exit to depart from the work area in specified circumstances would provide practical and effective worker protection in an emergency, without imposing a burden far out of proportion to any benefit.

OSHA has reviewed the comments regarding the difficulties expected with implementing the emergency provisions in the construction industry. In addition, OSHA has reviewed both the preambular portion of the Committee's recommendations (52 FR 26868) and the substantive requirements of 29 CFR 1910.38. OSHA believes that the Committee had intended to tailor this provision to better fit the nature of the changing worksites of the construction employee as it did in other areas of the standard. Examples of this are the use of historical monitoring data to satisfy the initial monitoring requirements for substantially similar construction operations, and the portable decontamination areas in the hygiene facilities paragraph. Looking also at the substantive elements found in the existing Employee emergency plan standard cited above, it appears that the only required element that would always be site specific is the emergency evacuation route. In light of these considerations, the language of paragraph (e)(1)(i) of the final construction standard reads as follows:

(i) A written plan for emergency situations shall be developed for each construction operation where there is a possibility of an emergency. The plan shall include procedures where the employer identifies emergency escape routes for his employees at each construction site before the construction operation begins. Appropriate portions of the plan shall be implemented in the event of an emergency. (Emphasis added.)

OSHA believes that this language will satisfy the concerns of the commenters and give effect to the Committee's intent without compromising the protection of the employee.

Paragraph (f). Exposure Monitoring

The standard also requires that the employers conduct monitoring to determine employee exposures to MDA. The standard requires initial determinations of employee exposures using frequencies and patterns of monitoring sufficient to represent with reasonable accuracy the exposures of employees. The standard would also require that monitoring be conducted no less frequently than once every 3 months if MDA exposure exceeds the PELs and once every 6 months if exposure is between the action level and the PELs. Section 6 (b)(7) of the Act mandates that standards promulgated shall, where appropriate, "provide for monitoring or measuring employee exposures at such locations and intervals, and in such a manner as may be necessary for the protection of employees" (29 U.S.C. 655(b)(7)). Based on the recommendations made by CACOSH in its "Report on Occupational Health Standards for the Construction Industry," May 16, 1980, CACOSH Docket (pp. 35-37), and the provisions of the Act, OSHA requires that the construction industry do the same sort of monitoring that is required of the general industry sectors.

Accordingly, the standard for construction includes several monitoring requirements, i.e., employers must perform monitoring of their employees' breathing zones that will accurately reflect and be representative of their exposures to MDA. In paragraph (f)(2), construction employers are required to conduct initial monitoring of employee exposures, unless: (1) the employer can demonstrate, on the basis of objective data, that the MDA-containing product or material being handled cannot cause exposures above the standard's action level, even under worst-case release conditions; or (2) the employer has historical monitoring or other data demonstrating that exposures on a particular job will be below the action level. Periodic monitoring is addressed in paragraph (f)(3) and is consistent with the toxicity of MDA. In recognizing the unique circumstances of working in a regulated area on a construction site, OSHA allows employers who are conducting MDA operations within a regulated area to forego periodic monitoring if the employees are all wearing supplied-air respirators while working in the regulated area.

Monitoring may be terminated when, in accordance with paragraph (f)(4), employers obtain confirmation by means of periodic monitoring that their employees' exposures are below the action level. Paragraph (f)(5) requires the employer to conduct additional monitoring when there has been a change in production process, chemical present, control equipment, personnel, or work practices which may result in new or additional exposures to MDA, or when the employer has any reason to suspect a change which may result in new or additional exposures. Paragraph (f)(6) provides the accuracy and precision requirements for the sampling methodology selected by the employer. The requirements in paragraph (f)(7) pertain to employee notification of monitoring results.

Although employers are required to determine the exposure of each employee exposed to MDA, this determination is not required to be based on separate measurements taken for each employee. Instead, the standard permits employers to use a "representative" measurement to characterize the exposures of more than one employee when these employees perform essentially the same job under the same conditions. For these types of situations, it may be sufficient for the employer to monitor one or a few of these employees to obtain data that are "representative" of the exposure of the remaining employees in the group. As permitted in paragraph (f)(1)(iii), representative personal sampling for employees engaged in similar work and exposed to similar concentrations of MDA can be achieved by measuring the exposure of that member of the exposed group who can reasonably be expected to have the highest exposure and then attributing this exposure level to the remaining employees in the group. In many work situations, this representative monitoring approach may be more cost-effective than individual monitoring of all employees to determine the exposures of affected employees. However, employers are free to use any monitoring approach that will correctly identify the breathing-zone exposures of their employees to airborne MDA.

Paragraph (f)(2) of the final rule contains requirements for initial monitoring for construction employees exposed to MDA. In this paragraph OSHA requires employers to conduct initial monitoring at the start of each new MDA job in order to assess the effectiveness of existing engineering controls and to provide information necessary for the proper selection of appropriate respirators.

OSHA believes that initial monitoring is essential for protecting employee health because it provides the employer with information for determining the necessity for using engineering controls, instituting or modifying work practices, and selecting appropriate respiratory protection. Recognizing the varied nature of construction projects, OSHA has required that initial monitoring for employee exposures be conducted at the start of each new construction project that involves the handling of MDA-containing materials.

Furthermore, however, Paragraph (f)(2) allows employers to dispense with initial monitoring if they can demonstrate by means of objective data that MDA-containing products or material cannot release airborne MDA in concentrations exceeding the action level. OSHA believes that employers may be able to obtain data from the manufacturers of MDA-containing products that demonstrate that these materials will not release MDA at levels that exceed the action level, even under worst case conditions. This exemption would relieve employers from monitoring when employees are handling MDA containing products that are not capable of releasing a significant amount of MDA.

OSHA also has included in paragraph (f)(2) an exemption from initial monitoring for employers who have historical monitoring data. OSHA included this exemption in recognition of the fact that many employers are currently conducting exposure monitoring on construction sites; this exemption would prevent these employers from having to repeat monitoring activity for construction jobs that are substantially similar to previous jobs for which monitoring was conducted.

However, such monitoring data must have been obtained from projects conducted by the employer that meet the following conditions:

(1) The data upon which judgments are based are scientifically sound and collected using methods that are sufficiently accurate and precise.

(2) The processes and work practices in use when the historical monitoring data were obtained are essentially the same as those to be used during the job for which initial monitoring will not be performed.

(3) The characteristics of the MDA- containing material being handled when the historical monitoring data were obtained are the same as those on the job for which initial monitoring will not be performed.

(4) Environmental conditions prevailing when the historical monitoring data were obtained are the same as for the job for which initial monitoring will not be performed.

Paragraph (g). Regulated Areas

The standard requires that signs be posted to alert employees to the existence of areas where MDA concentrations exceed or can be reasonably expected to exceed the permissible exposure limits or where employees are engaged in the handling, application, or use of MDA that can result in "dermal exposure to MDA." Paragraphs (g)(2) and (g)(3) require that the regulated area be demarcated in a manner that restricts entry to the area to authorized persons only. Respirators must be supplied to persons entering regulated areas as specified in paragraph (g)(4) and eating, drinking, smoking, and applying cosmetics are prohibited in such areas by paragraph (g)(5). These requirements are consistent with similar provisions in previous OSHA standards (Acrylonitrile, 29 CFR 1910.1045; Inorganic Arsenic, 29 CFR 1910.1018; Ethylene Oxide, 29 CFR 1910.1047; and Vinyl Chloride, 29 CFR 1910.1017) and with the general industry standard regulating occupational exposure to MDA.

Paragraph (h). Methods of Compliance

The standard governing occupational exposure to MDA requires that a combination of engineering controls and work practices be used to meet the exposure limits contained in the standard. The engineering control methods outlined in the standard include isolation, enclosure, exhaust ventilation, and dust collection. Work practices are also necessary for maintaining exposures at or below the PELs.

Local exhaust ventilation systems that are equipped with HEPA-filtered dust collection systems are required for use in the general industry standards and are likewise being required for use in the construction industry.

OSHA believes that in some instances but not as a general rule, that general exhaust ventilation systems may also be effective in reducing employee exposure to MDA in construction. Such systems are useful for reducing the concentration of MDA-containing materials and removing potentially harmful MDA particulates from the air through a HEPA filtration system. OSHA cautions employers, however, that the use of general exhaust ventilation will tend to spread MDA airborne contaminants unless the return air is passed through a HEPA filter. Vacuum cleaners that are equipped with HEPA filters are effective controls for cleaning MDA spills and performing clean-up, since the HEPA-filtered vacuum systems collect MDA-containing material and prevent it from becoming airborne.

Isolation and enclosure of operations where MDA-containing materials are being applied to surfaces during construction activities is an effective means of containing exposures. The burden would be on the Assistant Secretary, in a particular enforcement proceeding to demonstrate the feasibility of engineering controls required by paragraph (h)(1)(i)(D).

The prompt disposal of MDA-containing materials in leak-tight containers can be an effective work practice because MDA-containing materials sealed in disposal containers while they are still wet are less likely to pose a dermal exposure problem.

OSHA also notes the significance which respirator use has in controlling worker exposure to MDA resulting from spray application. In fact, OSHA believes that, in this instance, for the most part, a properly selected and functioning respirator serves as the only feasible control for ultimately separating the worker from his environment. OSHA recognizes that application of MDA through spray techniques would result in the potential for very high worker exposures and thus in these instances requires that respirators, in addition to the use of feasible engineering, controls be used.

Further, OSHA requires that compressed air not be used to remove MDA-containing materials. Using compressed air to clean MDA dust from surfaces results in the formation of large dust clouds that lead to excessive exposures of the worker and bystanders unless local exhaust ventilation is used. There was no indication, however, that using compressed air to blow MDA-containing dust from surfaces was a current practice.

Paragraph (i). Respiratory Protection

The standard for the construction industry requires that employers provide respirators at no cost to employees:

(1) during the interval necessary to install or implement feasible engineering and work practice controls;

(2) in operations such as maintenance and repair activities and spray application processes for which engineering and work practice controls are not feasible;

(3) in work situations where feasible engineering and work practice controls are not yet sufficient to reduce exposure to or below the PELs; and (4) in emergencies.

Employers are required under paragraph (i)(2) of the final rule to select appropriate respirators based on employee exposure levels that exist in the workplace. The required respirators range from half-mask air-purifying respirators equipped with high-efficiency filters for concentrations that do not exceed 10 times the PEL, to full-facepiece supplied-air respirators or SCBA when the concentration of MDA exceeds 1000 times the PEL. Employers are required to select respirators from those that are approved jointly by the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration under the provisions of 30 CFR Part 11.

Under paragraph (i)(3), employers are required to institute a respiratory protection program as required under 29 CFR 1910.134. The required program is to include among other things, (1) criteria for changing filter elements for air-purifying respirators, and (2) a policy permitting employees time to leave work areas to wash their faces and respirator facepieces to prevent skin irritation. Under paragraph (i)(5), the final standard requires that employers conduct qualitative or quantitative fit testing for all employees required to wear a negative-pressure respirator. The requirements for the use, selection, program elements, and fit testing of respirators are the same as those contained in the general industry standard.

Paragraph (j). Protective Work Clothing and Equipment

The construction standard, like the general industry standard, requires that all workers exposed to MDA be provided with personal protective clothing and equipment: i.e., coveralls, aprons, gloves, boot covers, and goggles. OSHA has imposed stringent provisions for the use of personal protective clothing because of the hazards associated with dermal absorption of MDA or MDA-containing materials. When non-disposable protective clothing is used, the employer is required by paragraph (j)(3) to launder the clothing in a manner that prevents the release of airborne MDA in excess of the PEL and to notify the person responsible for laundering. Paragraph (j)(2) requires employers to transport contaminated clothing in sealed impermeable bags or other impermeable containers. The requirements of paragraphs (j)(2) and (j)(3) are identical to the requirements of the general industry standard.

In addition, a requirement has been included that the personal protective equipment worn by employees be examined periodically to detect rips or tears, and that when rips or tears are detected in clothing they must be immediately mended, or the worksuit must be immediately replaced.

Also, OSHA allows disposable work suits to be used by construction workers handling MDA or MDA-containing products. OSHA believes that this type of clothing provides sufficient protection to the worker but eliminates the problems that may be involved in laundering and storing MDA-contaminated clothing on non-fixed work sites. OSHA recognizes that while disposable overalls may not be as durable and comfortable as cotton work clothes, they do not require laundering which would expose another workforce or the worker's family to MDA. OSHA, however, believes that non-disposable work clothes similar to those regulated in the general industry standard will provide sufficient protection for employees engaged in construction activities, provided that such clothing is properly cleaned after work and then laundered. OSHA, nonetheless, chooses to require performance language in its regulatory text which would allow the employer to choose the clothing which is appropriate.

OSHA also recognizes that heat stress is a concern when disposable protective clothing is used in hot environments. However, the use of protective clothing is necessary to protect employees from MDA exposure that may result from contaminated clothing. In situations in which heat stress is a concern, OSHA believes that employers should use appropriate work-rest regimens and provide heat stress monitoring that includes measuring employees' heart rates, body temperatures, and weight loss. If such measures are used to control heat stress, disposable protective clothing can be safely worn to provide the needed protection against MDA exposure.

Paragraph (k). Hygiene Facilities and Practices

The hygiene facilities requirements of the construction standard are similar to those in the general industry standard. For example, shower facilities are required wherever the possibility of employee exposure to airborne levels of MDA in excess of the action level exists. All workers required to wear personal protective equipment must have a place to change their street clothes and to store them separately from their work clothes.

Paragraph (k)(1)(i) of the construction standard modifies the language of the general industry standard to allow "decontamination areas," in recognition of the fact that the place where employees change from street clothing to work clothing and back again to street clothing is not always a separate room but may be merely a separate area of a larger space. This difference recognizes that it may not be feasible at some construction sites to provide a separate room with physical barriers.

"Decontamination area" is defined in the final standard to mean an area outside of but as near as practical to the regulated area, consisting of an equipment storage area, wash area, and clean change area, which is used for the decontamination of workers, materials, and equipment contaminated with MDA.

OSHA also requires "separate storage facilities" in recognition of the fact the employers must use portable storage facilities that can be transported from job to job. OSHA's intent in this provision is to ensure that street clothes are sufficiently separated from work and protective clothing and equipment in order to prevent contamination of employees' street clothing, and this can be accomplished by separate lockers, baskets, or other containers.

OSHA also requires the provision of clean lunch areas: i.e., areas that have airborne concentrations of MDA below the action level, where employees may consume food or beverages on site. This addition was recommended by CACOSH in its 1980 report. CACOSH recognized that permanent lunch rooms, such as exist on fixed worksites, were probably not feasible for the construction industry, due to the nonfixed nature of construction project worksites. See "Report on Occupational Health Standards for the Construction Industry," May 16, 1980, CACOSH Docket. The term "lunch area" is adopted by OSHA to indicate that a temporary facility, such as a separate trailer, would serve the purpose of protecting employee health.

Paragraph (l). Communication of MDA hazards to Employees

In paragraph (l) of the standard, includes requirements to ensure that the dangers of MDA-containing materials are communicated to employees by means of signs, labels, and employee information and training. The requirements for the signs and labels mandated in this section parallel those in OSHA's Hazard Communication standard (29 CFR 1910.1200).

(1) Signs and Labels. The construction standard includes specifications for signs to be posted at all locations where regulated areas have been established to indicate that concentrations of airborne MDA exceed or can be reasonably expected to exceed the PEL or where employees are engaged in activities that can result in "dermal exposure to MDA"; such signs are to bear the same legend as that required in the general industry standard.

The purpose of such signs is to minimize the number of employees in a regulated area by alerting them to the fact that they must have authorization from their employer and take the appropriate protective measures before entering. Furthermore, as discussed in the summary and explanation section for the standard for general industry, signs serve to apprise employees of the hazards to which they are exposed in the course of their employment, and foster cooperation between the employee and employer in controlling workplace hazards. The standard also requires that all MDA products and containers of MDA products, including waste containers, be labeled with appropriate information and with a warning statement against inhalation or dermal contact with MDA. These labeling requirements are consistent with those found in 1910.1200.

(2) Employee Information and Training. The training requirements are consistent with those found in 1910.1200, except that annual training is required in both the general industry and construction standards. The standard requires that training be provided to all employees prior to or at the time of initial assignment and at least yearly thereafter. Component areas to be covered in the training program include: (1) methods for recognizing MDA; (2) the health effects associated with MDA exposure; (3) the importance of necessary protective measures to minimize exposure including, as applicable, engineering controls, work practices, respirators, housekeeping and protective clothing, and any necessary instruction in the use of these controls; (4) the purpose, proper use, fitting instructions, and limitations of respirators, as described in 29 CFR 1910.134; (5) the appropriate work practices for performing the MDA related job; and (6) the medical surveillance program requirements. The employer may design and implement his own training program that contains these elements, or rely on third-party training programs. Finally, the standard requires that the employer make readily available to affected employees and provide to OSHA and NIOSH all written materials regarding the employee information and training program.

OSHA strongly believes that informing and training employees can reduce the incidence of work-related diseases caused by exposure to hazardous workplace conditions.

Paragraph (m). Housekeeping

The standard for the construction industry includes a housekeeping provision stipulating that (1) when vacuuming is used for cleanup, only HEPA-filtered equipment may be used; and (2) all waste, scrap, debris, bags, containers, equipment, and contaminated clothing must be collected and disposed of in sealed impermeable bags or in other closed impermeable containers. OSHA believes that these housekeeping practices reflect advances in vacuum filter technology and good hygiene practices, and are essential parts of any effective MDA control program. OSHA believes that the use of HEPA-filtered vacuums and proper disposal practices will considerably diminish the risk of generating airborne MDA during cleanup -- a potentially high-exposure activity -- and minimize the potential for dermal absorption of MDA. The required use of high-efficiency particulate air filters on vacuums employed for cleanup is not intended to preclude the use of other complementary cleanup methods, such as wet methods (where applicable). OSHA believes that the housekeeping requirements will aid in minimizing worker contact with MDA.

Paragraph (n). Medical Surveillance

Section 6(b)(7) of the OSH Act requires that, where appropriate, medical surveillance programs be included in OSHA health standards to aid in determining whether the health of workers is adversely affected by exposure to toxic substances. The medical surveillance requirements contained in this final MDA construction standard are designed to detect changes in liver function and signs or symptoms of acute liver disease.

OSHA requires that each employer must institute a medical surveillance program for all employees exposed to MDA as follows:

(1) Employees exposed at or above the action level to dusts or vapors for 30 or more days per year;

(2) Employees who are subject to dermal exposure to MDA for 15 or more days per year;

(3) Employees who have been exposed in an emergency situation;

(4) Employees whom the employer, based on results from compliance with (g)(8), has reason to believe are being dermally exposed; and

(5) Employees who show signs or symptoms of exposure.

The final language requires that the medical surveillance program provide each covered employee with an opportunity for a medical examination. Further, all examinations and procedures must be performed by or under the supervision of a licensed physician and be provided without cost to the employee. Clearly, a licensed physician is the appropriate person to supervise and evaluate a medical examinations. However, certain parts of the required examination do not necessarily require the physician's expertise and may be conducted by another person under the supervision of the physician.

OSHA also requires that exams be given at a reasonable time and place. It is necessary that exams be convenient and be provided without loss of pay to the employee to assure that they are taken.

The final standard allows the examining physician to prescribe the specific protocols to be included in the medical surveillance program. There are, however, some specific requirements, such as:

(i) comprehensive medical and work histories with special emphasis directed to an evaluation of other carcinogens to which the employee is exposed, and smoking and alcohol use;

(ii) comprehensive physical examination, with particular emphasis given to symptoms related to eye and skin irritation, and liver dysfunction;

(iii) complete urinalysis; and
(iv) screening for liver damage.

It is important to note that the employer is required to make any prescribed tests available more often than specified if recommended by the examining physician. OSHA also requires that the employer provide examinations recommended by the physician to any employee exposed to MDA under emergency conditions. Due to the effects of high short-term exposures, it appears prudent to monitor medically such affected employees. However, trivial exposures which are peripherally related to an emergency do not trigger the requirement.

The employer is also required to provide the physician with the following information: a copy of this standard and its appendices; a description of the affected employee's duties as they relate to the employee exposure level; and information from the employee's previous medical examinations which is not readily available to the examining physician. Making this information available to the physician will aid in the evaluation of the employee's health in relation to assigned duties and fitness to wear personal protective equipment.

The employer is required to obtain a written opinion from the examining physician that contains the results of the medical examinations; the physician's opinion as to whether the employee has any detected medical conditions which would place the employee at increased risk of material health impairment from exposure to MDA; any recommended restrictions upon the employee's exposure to MDA or upon the use of protective clothing or equipment, such as respirators; and a statement that the employee has been informed by the physician of the results of the medical examination and of any MDA-related medical conditions which require further explanation or treatment. This written opinion must not reveal specific findings or diagnoses unrelated to occupational exposure to MDA, and a copy of the opinion must be provided to the affected employee.

The requirement that a physician's opinion be in written form will ensure that employers have had the benefit of this information. The requirement that an employee be provided with a copy of the physician's written opinion will ensure that the employee is informed of the results of the medical examination. The purpose of requiring that specific findings or diagnoses, unrelated to occupational exposure to MDA, not be included in the written opinion is to encourage employees to take the medical examination by removing the concern that the employer will obtain information about their physical condition that has no relation to present occupational exposures.

Like the general industry standard this standard would also include a multiple physician review mechanism. This mechanism is required because OSHA believes this would aid in ensuring that employees take physical examinations. Finally, the standard contains provisions for removing an employee from exposure who has suffered reversible material impairment to health as a result of being exposed to MDA. OSHA believes that employees whose health has been adversely affected as a direct result of occupational exposure to MDA must be removed from exposure and must receive medical removal benefit protections. For a fuller discussion of the multiple physician review mechanism and the medical removal provisions, see the general industry summary above.

Paragraph (o). Recordkeeping

The final standard's requirements are consistent with Section 8(c)(3) of the OSH Act which provides for the promulgation of regulations requiring employers to maintain accurate records of employee exposures to potentially toxic substances or harmful physical agents which are required to be monitored or measured.

OSHA permits the use of objective data in order to be exempted from the standard. Records of objective data must be maintained to demonstrate that employees are not exposed to excessive airborne MDA concentrations or "dermally exposed to MDA", as defined.

For this final construction standard, OSHA also permits the use of historical monitoring data in order to meet the requirements for initial monitoring found in paragraph (f)(2) of this section. Records of historical monitoring data must be maintained to demonstrate that employees are not exposed to airborne concentrations of MDA in excess of the action level. While this specific recordkeeping language was not in the NPRM its substantive basis is found both in paragraph (f)(2) found at 54 FR 20731 and the definition of "Objective and historical data" found on the page before. In addition, this language is taken verbatim from the Committee's preamble at 52 FR 26869. OSHA believes that this language will help to clarify what is expected from an employer who chooses to use historical monitoring data to satisfy his initial monitoring obligations under the standard.

OSHA also requires that records be kept to identify the employee monitored and to reflect the employee's exposure accurately. Specifically, records must include the following information: (a) the names and social security numbers of the employees sampled; (b) the number, duration, and results of each of the samples taken, including a description of the representative sampling procedure and equipment used to determine employee exposure where applicable; (c) a description of the operation involving exposure to MDA which is being monitored and the date on which monitoring is performed; (d) the type of respiratory protective devices, if any, worn by the employee; and (e) a description of the sampling and analytical methods used, and evidence of their accuracy.

OSHA also includes a provision for requiring the employer to keep an accurate medical record for each employee subject to medical surveillance.

Section 8(c) of the Act authorizes the promulgation of regulations requiring any employer to keep such records regarding the employer's activities relating to the Act as are necessary or appropriate for the enforcement of the Act or for developing information regarding the causes and prevention of occupational illnesses. OSHA believes that medical records, like exposure monitoring records, are necessary and appropriate to both the enforcement of the standard and the development of information regarding the causes and prevention of illness.

As explained above, it is necessary to relate employees' medical conditions to their exposures to develop information regarding cause and prevention. Medical records are necessary and appropriate for this purpose. In addition, medical records are necessary for the proper evaluation of the employee's health.

The employer is also required to keep a record of any employee's medical removal and return to work status.

The standard requires that all records required to be kept shall be made available upon request to the Assistant Secretary and the Director of NIOSH for examination and copying. Access to these records is necessary for the agencies to monitor compliance with the standard. These records may also contain essential information which is necessary for the agencies to carry out their other statutory responsibilities.

The standard also provides for employees, former employees, and their designated representatives to have access to mandated records upon request. Section 8(c)(3) of the Act explicitly provides "employees or their representatives" with an opportunity to observe monitoring and to have access to the records of monitoring and exposures to toxic substances; and several other provisions of the Act contemplate that employees and their representatives are entitled to play an active role in the enforcement of the Act. Employees and their representatives need to know relevant information concerning employee exposure to toxic substances and their health consequences if they are to benefit fully from these statutory rights.

In addition, access to exposure and medical records by employees, designated representatives, and OSHA is to be provided in accordance with 29 CFR 1910.20. Section 1910.20 is OSHA's generic standard for access to employee exposure and medical records (45 FR 35212). By its terms, it applies to records required by specific standards, such as this MDA standard, as well as records which are voluntarily created by employers. In general, it provides for unrestricted employee and designated representative access to exposure records. Unrestricted access to both kinds of records is allowed, but access to personally identifiable records is made subject to rules of agency practice and procedure concerning OSHA access to employee medical records, which have been published at 29 CFR 1913.10. An extensive discussion of the provisions and rationale for 1920.20 may be found at 45 FR 35312; the discussion of 1913.10 may be found at 45 FR 35384.

It is necessary to keep records for extended periods because of the long latency periods commonly observed for carcinogens. Cancer often cannot be detected until 20 or more years after onset of exposure. The extended retention period is therefore needed for two purposes. Diagnosis of disease in employees is assisted by having present and past exposure data as well as the results of the medical exams. Retaining records for extended periods also makes it possible at some future date to review the adequacy of the standard.

The time periods required for retention of exposure records and medical records are thirty years, and period of employment plus thirty years, respectively. These retention periods are consistent with those in the OSHA records access standard.

The standard requires certain employers to notify the Director in writing at least 3 months prior to the disposal of the records. Section 1910.20(h) contains further requirements regarding the transfer of records.

To increase the effectiveness of training goals the standard requires that the training material be made available, without cost, to all affected employees or their representatives.

OSHA recognizes the transient nature of the construction industry and the difficulties which this industry may have with recordkeeping requirements; it is for this reason that OSHA would not mandate the specific methods of recordkeeping. Employers are free to use the services of competent organizations such as industry trade associations and employee associations to maintain the required records. To reduce the costs and facilitate the recordkeeping some groups currently use centralized medical recordkeeping financed through employer contributions.

Centralized recordkeeping could be instrumental in alleviating the problem of lost records associated with the transient nature of the construction workforce and the frequency of business closures in this sector.

Paragraph (p). Observation of Monitoring

The final standard also includes a provision for observation of exposure monitoring. This provision is in accordance with section 8(c) of the OSH Act which requires that employers provide employees and their representatives with the opportunity to observe monitoring of employee exposures to toxic substances or harmful physical agents. Observation procedures are set forth which require the observer, whether it be an employee or a designated representative, to be provided with the personal protective clothing and equipment that is required to be worn by the employees who are working in the area. The employer is required to assure the use of such clothing and equipment or respirators and is responsible for requiring that the observer complies with all other applicable safety and health procedures.

Paragraph (q). Effective dates.

The standard becomes effective September 9, 1992. The effective date established in the final standard remains the same as the date which appeared in the proposed rule.

Paragraph (r). Appendices

Five appendices have been included at the end of this final standard. Appendices A,B, C, and D have been included primarily for purposes of information. None of the statements contained in Appendices A,B,C, and D should be construed as establishing a mandatory requirement not otherwise imposed by the standard, or as detracting from an obligation which the standard does impose. However, the protocols for respiratory fit testing in Appendix E are mandatory.

Appendix A contains information on the description and exposure levels of MDA. Also provided in Appendix A is information on the health hazards associated with exposure, descriptions of protective clothing and equipment, emergency and first aid procedures, medical requirements, provisions for the observation of monitoring, access to exposure and medical records, and precautions for the safe use, handling, and storage of MDA.

Appendix B contains "substance technical guidelines" for MDA, including physical and chemical data, spill and leak procedures, including waste disposal methods, and other miscellaneous precautions for the safe handling of MDA.

Appendix C contains the medical surveillance guidelines for MDA. Included in these guidelines are the description of the routes of entry, the toxicology and symptoms and signs associated with MDA exposure, information on the treatment of acute toxic effects, and surveillance and preventive considerations, including hematology guidelines which may be useful to physicians in conducting the medical surveillance program required by paragraph (n) of this final standard.

Appendix D gives details of the sampling and analytical methods for use in monitoring employee exposures to MDA.

Appendix E gives detailed fit testing procedures that are to be followed for qualitative or quantitative fit testing of negative pressure respirators. Various protocols for qualitative and quantitative fit tests are outlined in detail.

All the Appendices are designed to aid the employer in complying with the requirements of the standard. Paragraph (l) of this final standard on the "communication of MDA hazards to employees" specifically requires that the contents of the standard and Appendices A and B be made available to affected employees. Information contained in Appendix C on medical surveillance is to be explained to affected employees. Appendix C also provides information needed by the physician to evaluate the results of the medical examination.

Paragraph (s). Start-up dates.

The final standard contains start up dates for the various standard provisions. These dates go into effect based on the effective date. The dates originally proposed in the MDA rule have been modified to reflect a more logical schedule for compliance. These dates are based on economic and technological considerations discussed in the regulatory impact analysis.

[57 FR 35630, Aug. 10, 1992]

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