29 Cfr 1926.60

29 CFR 1926.60 (up to date as of 5/05/2025)
Methylenedianiline.

29 CFR 1926.60 (May 5, 2025)

This content is from the eCFR and is authoritative but unofficial.

Title 29 —Labor
Subtitle B —Regulations Relating to Labor
Chapter XVII —Occupational Safety and Health Administration, Department of Labor
Part 1926 —Safety and Health Regulations for Construction
Subpart D —Occupational Health and Environmental Controls
Authority: 40 U.S.C. 3704; 29 U.S.C. 653, 655, and 657; and Secretary of Labor's Order No. 12-71 (36 FR 8754), 8-76 (41 FR
25059), 9-83 (48 FR 35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 50017), 5-2002 (67 FR 65008), 5-2007 (72 FR
31159), 4-2010 (75 FR 55355), 1-2012 (77 FR 3912), or 8-2020 (85 FR 58393), as applicable; and 29 CFR part 1911. Sections
1926.59, 1926.60, and 1926.65 also issued under 5 U.S.C. 553 and 29 CFR part 1911. Section 1926.61 also issued under 49
U.S.C. 1801-1819 and 5 U.S.C. 553. See Subpart D of Part 1926 for more
Authority: 40 U.S.C. 3704; 29 U.S.C. 653, 655, and 657; and Secretary of Labor's Order No. 12-71 (36 FR 8754), 8-76 (41 FR
25059), 9-83 (48 FR 35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 50017), 5-2002 (67 FR 65008), 5-2007 (72 FR
31159), 4-2010 (75 FR 55355), 1-2012 (77 FR 3912), or 8-2020 (85 FR 58393), as applicable; and 29 CFR part 1911, unless
otherwise noted Sections 1926.58, 1926.59, 1926.60, and 1926.65 also issued under 5 U.S.C. 553 and 29 CFR part 1911.
Section 1926.61 also issued under 49 U.S.C. 1801-1819 and 5 U.S.C. 553. See Part 1926 for more
Source: 44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, unless otherwise noted.

Editorial Notes: 1. At 44 FR 8577, Feb. 9, 1979, and corrected at 44 FR 20940, Apr. 6, 1979, OSHA reprinted
without change the entire text of 29 CFR part 1926 together with certain General Industry Occupational Safety and
Health Standards contained in 29 CFR part 1910, which have been identified as also applicable to construction
work. This republication developed a single set of OSHA regulations for both labor and management forces within
the construction industry.
2. Nomenclature changes to part 1926 appear at 84 FR 21597, May 14, 2019.

§ 1926.60 Methylenedianiline.
(a) Scope and application.
(1) This section applies to all construction work as defined in 29 CFR 1910.12(b), in which there is
exposure to MDA, including but not limited to the following:
(i)

Construction, alteration, repair, maintenance, or renovation of structures, substrates, or portions
thereof, that contain MDA;

(ii) Installation or the finishing of surfaces with products containing MDA;
(iii) MDA spill/emergency cleanup at construction sites; and
(iv) Transportation, disposal, storage, or containment of MDA or products containing MDA on the
site or location at which construction activities are performed.
(2) Except as provided in paragraphs (a)(7) and (f)(5) of this section, this section does not apply to the
processing, use, and handling of products containing MDA where initial monitoring indicates that the
product is not capable of releasing MDA in excess of the action level under the expected conditions
of processing, use, and handling which will cause the greatest possible release; and where no
“dermal exposure to MDA” can occur.

29 CFR 1926.60(a)(2) (enhanced display)

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29 CFR 1926.60 (up to date as of 5/05/2025)
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29 CFR 1926.60(a)(3)

(3) Except as provided in paragraph (a)(7) of this section, this section does not apply to the processing,
use, and handling of products containing MDA where objective data are reasonably relied upon
which demonstrate the product is not capable of releasing MDA under the expected conditions of
processing, use, and handling which will cause the greatest possible release; and where no “dermal
exposure to MDA” can occur.
(4) Except as provided in paragraph (a)(7) of this section, this section does not apply to the storage,
transportation, distribution or sale of MDA in intact containers sealed in such a manner as to contain
the MDA dusts, vapors, or liquids, except for the provisions of 29 CFR 1910.1200 and paragraph (e)
of this section.
(5) Except as provided in paragraph (a)(7) of this section, this section does not apply to materials in any
form which contain less than 0.1% MDA by weight or volume.
(6) Except as provided in paragraph (a)(7) of this section, this section does not apply to “finished articles
containing MDA.”
(7) Where products containing MDA are exempted under paragraphs (a)(2) through (a)(6) of this section,
the employer shall maintain records of the initial monitoring results or objective data supporting that
exemption and the basis for the employer's reliance on the data, as provided in the recordkeeping
provision of paragraph (o) of this section.
(b) Definitions. For the purpose of this section, the following definitions shall apply:
Action level means a concentration of airborne MDA of 5 ppb as an eight (8)-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S.
Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the
person to enter a regulated area, or any person entering such an area as a designated representative
of employees for the purpose of exercising the right to observe monitoring and measuring
procedures under paragraph (p) of this section, or any other person authorized by the Act or
regulations issued under the Act.
Container means any barrel, bottle, can, cylinder, drum, reaction vessel, storage tank, commercial
packaging or the like, but does not include piping systems.
Decontamination area means 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.
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% by weight or volume; and

(ii) Materials other than “finished articles” containing MDA in concentrations greater than 0.1% by
weight or volume.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department
of Health and Human Services, or designee.

29 CFR 1926.60(b) “Director” (enhanced display)

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29 CFR 1926.60 (up to date as of 5/05/2025)
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29 CFR 1926.60(b) “Emergency”

Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or
failure of control equipment which results in an unexpected and potentially hazardous release of
MDA.
Employee exposure means exposure to MDA which would occur if the employee were not using respirators
or protective work clothing and equipment.
Finished article containing MDA is defined as a manufactured item:
(i)

Which is formed to a specific shape or design during manufacture;

(ii) Which has end use function(s) dependent in whole or part upon its shape or design during end
use; and
(iii) Where applicable, is an item which is fully cured by virtue of having been subjected to the
conditions (temperature, time) necessary to complete the desired chemical reaction.
Historical monitoring data means monitoring data for construction jobs that meet the following conditions:
(i)

The data upon which judgments are based are scientifically sound and were collected using
methods that are sufficiently accurate and precise;

(ii) The processes and work practices that were 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;
(iii) 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;
(iv) Environmental conditions prevailing when the historical monitoring data were obtained are the
same as those on the job for which initial monitoring will not be performed; and
(v) Other data relevant to the operations, materials, processing, or employee exposures covered by
the exception are substantially similar. The data must be scientifically sound, the
characteristics of the MDA containing material must be similar and the environmental
conditions comparable.
4,4

′Methylenedianiline or MDA means the chemical; 4,4′-diaminodiphenylmethane, Chemical Abstract
Service Registry number 101-77-9, in the form of a vapor, liquid, or solid. The definition also includes
the salts of MDA.

Regulated Areas means areas where airborne concentrations of MDA exceed or can reasonably be
expected to exceed, the permissible exposure limits, or where “dermal exposure to MDA” can occur.
STEL means short term exposure limit as determined by any 15-minute sample period.
(c) Permissible exposure limits. The employer shall assure that no employee is exposed to an airborne
concentration of MDA in excess of ten parts per billion (10 ppb) as an 8-hour time-weighted average and a
STEL of one hundred parts per billion (100 ppb).
(d) Communication among employers. On multi-employer worksites, an employer performing work involving
the application of MDA or materials containing MDA for which establishment of one or more regulated
areas is required shall inform other employers on the site of the nature of the employer's work with MDA
and of the existence of, and requirements pertaining to, regulated areas.
29 CFR 1926.60(d) (enhanced display)

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29 CFR 1926.60 (up to date as of 5/05/2025)
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29 CFR 1926.60(e)

(e) Emergency situations —
(1) Written plan.
(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.

(ii) The plan shall specifically provide that employees engaged in correcting emergency conditions
shall be equipped with the appropriate personal protective equipment and clothing as required
in paragraphs (i) and (j) of this section until the emergency is abated.
(iii) The plan shall specifically include provisions for alerting and evacuating affected employees as
well as the applicable elements prescribed in 29 CFR 1910.38 and 29 CFR 1910.39, “Emergency
action plans” and “Fire prevention plans,” respectively.
(2) Alerting employees. Where there is the possibility of employee exposure to MDA due to an
emergency, means shall be developed to promptly alert employees who have the potential to be
directly exposed. Affected employees not engaged in correcting emergency conditions shall be
evacuated immediately in the event that an emergency occurs. Means shall also be developed for
alerting other employees who may be exposed as a result of the emergency.
(f) Exposure monitoring —
(1) General.
(i)

Determinations of employee exposure shall be made from breathing zone air samples that are
representative of each employee's exposure to airborne MDA over an eight (8) hour period.
Determination of employee exposure to the STEL shall be made from breathing zone air
samples collected over a 15 minute sampling period.

(ii) Representative employee exposure shall be determined on the basis of one or more samples
representing full shift exposure for each shift for each job classification in each work area
where exposure to MDA may occur.
(iii) Where the employer can document that exposure levels are equivalent for similar operations in
different work shifts, the employer shall only be required to determine representative employee
exposure for that operation during one shift.
(2) Initial monitoring. Each employer who has a workplace or work operation covered by this standard
shall perform initial monitoring to determine accurately the airborne concentrations of MDA to which
employees may be exposed unless:
(i)

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

(ii) The employer has historical monitoring or other data demonstrating that exposures on a
particular job will be below the action level.
(3) Periodic monitoring and monitoring frequency.

29 CFR 1926.60(f)(3) (enhanced display)

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29 CFR 1926.60 (up to date as of 5/05/2025)
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(i)

29 CFR 1926.60(f)(3)(i)

If the monitoring required by paragraph (f)(2) of this section reveals employee exposure at or
above the action level, but at or below the PELs, the employer shall repeat such monitoring for
each such employee at least every six (6) months.

(ii) If the monitoring required by paragraph (f)(2) of this section reveals employee exposure above
the PELs, the employer shall repeat such monitoring for each such employee at least every
three (3) months.
(iii) Employers who are conducting MDA operations within a regulated area can forego periodic
monitoring if the employees are all wearing supplied-air respirators while working in the
regulated area.
(iv) The employer may alter the monitoring schedule from every three months to every six months
for any employee for whom two consecutive measurements taken at least 7 days apart indicate
that the employee exposure has decreased to below the PELs but above the action level.
(4) Termination of monitoring.
(i)

If the initial monitoring required by paragraph (f)(2) of this section reveals employee exposure
to be below the action level, the employer may discontinue the monitoring for that employee,
except as otherwise required by paragraph (f)(5) of this section.

(ii) If the periodic monitoring required by paragraph (f)(3) of this section reveals that employee
exposures, as indicated by at least two consecutive measurements taken at least 7 days apart,
are below the action level the employer may discontinue the monitoring for that employee,
except as otherwise required by paragraph (f)(5) of this section.
(5) Additional monitoring. The employer shall institute the exposure monitoring required under
paragraphs (f)(2) and (f)(3) of this section when there has been a change in production process,
chemicals 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.
(6) Accuracy of monitoring. Monitoring shall be accurate, to a confidence level of 95 percent, to within
plus or minus 25 percent for airborne concentrations of MDA.
(7) Employee notification of monitoring results.
(i)

The employer must, as soon as possible but no later than 5 working days after the receipt of the
results of any monitoring performed under this section, notify each affected employee of these
results either individually in writing or by posting the results in an appropriate location that is
accessible to employees.

(ii) The written notification required by paragraph (f)(7)(i) of this section shall contain the
corrective action being taken by the employer or any other protective measures which have
been implemented to reduce the employee exposure to or below the PELs, wherever the PELs
are exceeded.
(8) Visual monitoring. The employer shall make routine inspections of employee hands, face and
forearms potentially exposed to MDA. Other potential dermal exposures reported by the employee
must be referred to the appropriate medical personnel for observation. If the employer determines
that the employee has been exposed to MDA the employer shall:
(i)

Determine the source of exposure;

29 CFR 1926.60(f)(8)(i) (enhanced display)

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29 CFR 1926.60(f)(8)(ii)

(ii) Implement protective measures to correct the hazard; and
(iii) Maintain records of the corrective actions in accordance with paragraph (o) of this section.
(g) Regulated areas —
(1) Establishment —
(i)

Airborne exposures. The employer shall establish regulated areas where airborne
concentrations of MDA exceed or can reasonably be expected to exceed, the permissible
exposure limits.

(ii) Dermal exposures. Where employees are subject to “dermal exposure to MDA” the employer
shall establish those work areas as regulated areas.
(2) Demarcation. Regulated areas shall be demarcated from the rest of the workplace in a manner that
minimizes the number of persons potentially exposed.
(3) Access. Access to regulated areas shall be limited to authorized persons.
(4) Personal protective equipment and clothing. Each person entering a regulated area shall be supplied
with, and required to use, the appropriate personal protective clothing and equipment in accordance
with paragraphs (i) and (j) of this section.
(5) Prohibited activities. The employer shall ensure that employees do not eat, drink, smoke, chew
tobacco or gum, or apply cosmetics in regulated areas.
(h) Methods of compliance —
(1) Engineering controls and work practices and respirators.
(i)

The employer shall use one or any combination of the following control methods to achieve
compliance with the permissible exposure limits prescribed by paragraph (c) of this section:
(A) Local exhaust ventilation equipped with HEPA filter dust collection systems;
(B) General ventilation systems;
(C) Use of workpractices; or
(D) Other engineering controls such as isolation and enclosure that the Assistant Secretary
can show to be feasible.

(ii) Wherever the feasible engineering controls and work practices “which can be instituted are not
sufficient to reduce employee exposure to or below the PELs, the employer shall use them to
reduce employee exposure to the lowest levels achievable by these controls and shall
supplement them by the use of respiratory protective devices which comply with the
requirements of paragraph (i) of this section.
(2) Special Provisions. For workers engaged in spray application methods, respiratory protection must
be used in addition to feasible engineering controls and work practices to reduce employee exposure
to or below the PELs.
(3) Prohibitions. Compressed air shall not be used to remove MDA, unless the compressed air is used in
conjunction with an enclosed ventilation system designed to capture the dust cloud created by the
compressed air.
29 CFR 1926.60(h)(3) (enhanced display)

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29 CFR 1926.60(h)(4)

(4) Employee rotation. The employer shall not use employee rotation as a means of compliance with the
exposure limits prescribed in paragraph (c) of this section.
(5) Compliance program.
(i)

The employer shall establish and implement a written program to reduce employee exposure to
or below the PELs by means of engineering and work practice controls, as required by
paragraph (h)(1) of this section, and by use of respiratory protection where permitted under this
section.

(ii) Upon request this written program shall be furnished for examination and copying to the
Assistant Secretary, the Director, affected employees and designated employee
representatives. The employer shall review and, as necessary, update such plans at least once
every 12 months to make certain they reflect the current status of the program.
(i)

Respiratory protection —
(1) General. For employees who use respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements of this paragraph.
Respirators must be used during:
(i)

Periods necessary to install or implement feasible engineering and work-practice controls.

(ii) Work operations, such as maintenance and repair activities and spray-application processes,
for which engineering and work-practice controls are not feasible.
(iii) Work operations for which feasible engineering and work-practice controls are not yet sufficient
to reduce employee exposure to or below the PELs.
(iv) Emergencies.
(2) Respirator program. The employer must implement a respiratory protection program in accordance
with § 1910.134 (b) through (d) (except (d)(1)(iii)), and (f) through (m), which covers each employee
required by this section to use a respirator.
(3) Respirator selection.
(i)

Employers must:
(A) Select, and provide to employees, the appropriate respirators specified in paragraph
(d)(3)(i)(A) of 29 CFR 1910.134.
(B) Provide HEPA filters for powered and non-powered air-purifying respirators.
(C) For escape, provide employees with one of the following respirator options: Any selfcontained breathing apparatus with a full facepiece or hood operated in the positivepressure or continuous-flow mode; or a full facepiece air-purifying respirator.
(D) Provide a combination HEPA filter and organic vapor canister or cartridge with air-purifying
respirators when MDA is in liquid form or used as part of a process requiring heat.

(ii) An employee who cannot use a negative-pressure respirator must be given the option of using a
positive-pressure respirator, or a supplied-air respirator operated in the continuous-flow or
pressure-demand mode.
(j)

Protective work clothing and equipment —

29 CFR 1926.60(j) (enhanced display)

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29 CFR 1926.60(j)(1)

(1) Provision and use. Where employees are subject to dermal exposure to MDA, where liquids
containing MDA can be splashed into the eyes, or where airborne concentrations of MDA are in
excess of the PEL, the employer shall provide, at no cost to the employee, and ensure that the
employee uses, appropriate protective work clothing and equipment which prevent contact with
MDA such as, but not limited to:
(i)

Aprons, coveralls or other full-body work clothing;

(ii) Gloves, head coverings, and foot coverings; and
(iii) Face shields, chemical goggles; or
(iv) Other appropriate protective equipment which comply with 29 CFR 1910.133.
(2) Removal and storage.
(i)

The employer shall ensure that, at the end of their work shift, employees remove MDAcontaminated protective work clothing and equipment that is not routinely removed throughout
the day in change areas provided in accordance with the provisions in paragraph (k) of this
section.

(ii) The employer shall ensure that, during their work shift, employees remove all other MDAcontaminated protective work clothing or equipment before leaving a regulated area.
(iii) The employer shall ensure that no employee takes MDA-contaminated work clothing or
equipment out of the decontamination areas, except those employees authorized to do so for
the purpose of laundering, maintenance, or disposal.
(iv) MDA-contaminated work clothing or equipment shall be placed and stored and transported in
sealed, impermeable bags, or other closed impermeable containers.
(v) Containers of MDA-contaminated protective work clothing or equipment which are to be taken
out of decontamination areas or the workplace for cleaning, maintenance, or disposal, shall
bear labels warning of the hazards of MDA.
(3) Cleaning and replacement.
(i)

The employer shall provide the employee with clean protective clothing and equipment. The
employer shall ensure that protective work clothing or equipment required by this paragraph is
cleaned, laundered, repaired, or replaced at intervals appropriate to maintain its effectiveness.

(ii) The employer shall prohibit the removal of MDA from protective work clothing or equipment by
blowing, shaking, or any methods which allow MDA to re-enter the workplace.
(iii) The employer shall ensure that laundering of MDA-contaminated clothing shall be done so as to
prevent the release of MDA in the workplace.
(iv) Any employer who gives MDA-contaminated clothing to another person for laundering shall
inform such person of the requirement to prevent the release of MDA.
(v) The employer shall inform any person who launders or cleans protective clothing or equipment
contaminated with MDA of the potentially harmful effects of exposure.
(4) Visual Examination.

29 CFR 1926.60(j)(4) (enhanced display)

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(i)

29 CFR 1926.60(j)(4)(i)

The employer shall ensure that employees' work clothing is examined periodically for rips or
tears that may occur during performance of work.

(ii) When rips or tears are detected, the protective equipment or clothing shall be repaired and
replaced immediately.
(k) Hygiene facilities and practices —
(1) General.
(i)

The employer shall provide decontamination areas for employees required to work in regulated
areas or required by paragraph (j)(1) of this section to wear protective clothing. Exception: In
lieu of the decontamination area requirement specified in paragraph (k)(1)(i) of this section, the
employer may permit employees engaged in small scale, short duration operations, to clean
their protective clothing or dispose of the protective clothing before such employees leave the
area where the work was performed.

(ii) Change areas. The employer shall ensure that change areas are equipped with separate storage
facilities for protective clothing and street clothing, in accordance with 29 CFR 1910.141(e).
(iii) Equipment area. The equipment area shall be supplied with impermeable, labeled bags and
containers for the containment and disposal of contaminated protective clothing and
equipment.
(2) Shower area.
(i)

Where feasible, shower facilities shall be provided which comply with 29 CFR 1910.141(d)(3)
wherever the possibility of employee exposure to airborne levels of MDA in excess of the
permissible exposure limit exists.

(ii) Where dermal exposure to MDA occurs, the employer shall ensure that materials spilled or
deposited on the skin are removed as soon as possible by methods which do not facilitate the
dermal absorption of MDA.
(3) Lunch Areas.
(i)

Whenever food or beverages are consumed at the worksite and employees are exposed to MDA
the employer shall provide clean lunch areas were MDA levels are below the action level and
where no dermal exposure to MDA can occur.

(ii) The employer shall ensure that employees wash their hands and faces with soap and water
prior to eating, drinking, smoking, or applying cosmetics.
(iii) The employer shall ensure that employees do not enter lunch facilities with contaminated
protective work clothing or equipment.
(l)

Communication of hazards to employees —
(1) Hazard communication. The employer shall include Methylenedianiline (MDA) in the program
established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The
employer shall ensure that each employee has access to labels on containers of MDA and safety
data sheets, and is trained in accordance with the provisions of HCS and paragraph (l)(3) of this
section. The employer shall ensure that at least the following hazards are addressed: Cancer; liver
effects; and skin sensitization.

29 CFR 1926.60(l)(1) (enhanced display)

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29 CFR 1926.60(l)(2)

(2) Signs and labels —
(i)

Signs.
(A) The employer shall post and maintain legible signs demarcating regulated areas and
entrances or access-ways to regulated areas that bear the following legend:
DANGER
MDA
MAY CAUSE CANCER
CAUSES DAMAGE TO THE LIVER
RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING MAY BE REQUIRED IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(B) Prior to June 1, 2016, employers may use the following legend in lieu of that specified in
paragraph (l)(2)(i)(A) of this section:
DANGER
MDA
MAY CAUSE CANCER
LIVER TOXIN
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE CLOTHING MAY BE REQUIRED TO BE WORN IN THIS AREA

(ii) Labels.
(A) The employer shall ensure that labels or other appropriate forms of warning are provided
for containers of MDA within the workplace. The labels shall comply with the
requirements of § 1910.1200(f) and shall include at least the following information for
pure MDA and mixtures containing MDA:
DANGER
CONTAINS MDA
MAY CAUSE CANCER
CAUSES DAMAGE TO THE LIVER

29 CFR 1926.60(l)(2)(ii)(A) (enhanced display)

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29 CFR 1926.60(l)(2)(ii)(B)

(B) Prior to June 1, 2015, employers may include the following information workplace labels in
lieu of the labeling requirements in paragraph (l)(2)(ii)(A) of this section:
(1) For Pure MDA:
DANGER
CONTAINS MDA
MAY CAUSE CANCER
LIVER TOXIN
(2) For mixtures containing MDA:
DANGER
CONTAINS MDA
CONTAINS MATERIALS WHICH MAY CAUSE CANCER
LIVER TOXIN
(3) Information and training.
(i)

The employer shall provide employees with information and training on MDA, in accordance
with 29 CFR 1910.1200(h), at the time of initial assignment and at least annually thereafter.

(ii) In addition to the information required under 29 CFR 1910.1200, the employer shall:
(A) Provide an explanation of the contents of this section, including appendices A and B of
this section, and indicate to employees where a copy of the standard is available;
(B) Describe the medical surveillance program required under paragraph (n) of this section,
and explain the information contained in appendix C of this section; and
(C) Describe the medical removal provision required under paragraph (n) of this section.
(4) Access to training materials.
(i)

The employer shall make readily available to all affected employees, without cost, all written
materials relating to the employee training program, including a copy of this regulation.

(ii) The employer shall provide to the Assistant Secretary and the Director, upon request, all
information and training materials relating to the employee information and training program.
(m) Housekeeping.
(1) All surfaces shall be maintained as free as practicable of visible accumulations of MDA.
(2) The employer shall institute a program for detecting MDA leaks, spills, and discharges, including
regular visual inspections of operations involving liquid or solid MDA.
(3) All leaks shall be repaired and liquid or dust spills cleaned up promptly.
29 CFR 1926.60(m)(3) (enhanced display)

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29 CFR 1926.60(m)(4)

(4) Surfaces contaminated with MDA may not be cleaned by the use of compressed air.
(5) Shoveling, dry sweeping, and other methods of dry clean-up of MDA may be used where HEPA
filtered vacuuming and/or wet cleaning are not feasible or practical.
(6) Waste, scrap, debris, bags, containers, equipment, and clothing contaminated with MDA shall be
collected and disposed of in a manner to prevent the re-entry of MDA into the workplace.
(n) Medical surveillance —
(1) General.
(i)

The employer shall make available a medical surveillance program for employees exposed to
MDA under the following circumstances:
(A) Employees exposed at or above the action level for 30 or more days per year;
(B) Employees who are subject to dermal exposure to MDA for 15 or more days per year;
(C) Employees who have been exposed in an emergency situation;
(D) Employees whom the employer, based on results from compliance with paragraph (f)(8) of
this section, has reason to believe are being dermally exposed; and
(E) Employees who show signs or symptoms of MDA exposure.

(ii) The employer shall ensure that all medical examinations and procedures are performed by or
under the supervision of a licensed physician at a reasonable time and place, and provided
without cost to the employee.
(2) Initial examinations.
(i)

Within 150 days of the effective date of this standard, or before the time of initial assignment,
the employer shall provide each employee covered by paragraph (n)(1)(i) of this section with a
medical examination including the following elements:
(A) A detailed history which includes:
(1) Past work exposure to MDA or any other toxic substances;
(2) A history of drugs, alcohol, tobacco, and medication routinely taken (duration and
quantity); and
(3) A history of dermatitis, chemical skin sensitization, or previous hepatic disease.
(B) A physical examination which includes all routine physical examination parameters, skin
examination, and examination for signs of liver disease.
(C) Laboratory tests including:
(1) Liver function tests and
(2) Urinalysis.
(D) Additional tests as necessary in the opinion of the physician.

(ii) No initial medical examination is required if adequate records show that the employee has been
examined in accordance with the requirements of this section within the previous six months
prior to the effective date of this standard or prior to the date of initial assignment.
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29 CFR 1926.60(n)(3)

(3) Periodic examinations.
(i)

The employer shall provide each employee covered by this section with a medical examination
at least annually following the initial examination. These periodic examinations shall include at
least the following elements:
(A) A brief history regarding any new exposure to potential liver toxins, changes in drug,
tobacco, and alcohol intake, and the appearance of physical signs relating to the liver, and
the skin;
(B) The appropriate tests and examinations including liver function tests and skin
examinations; and
(C) Appropriate additional tests or examinations as deemed necessary by the physician.

(ii) If in the physician's opinion the results of liver function tests indicate an abnormality, the
employee shall be removed from further MDA exposure in accordance with paragraph (n)(9) of
this section. Repeat liver function tests shall be conducted on advice of the physician.
(4) Emergency examinations. If the employer determines that the employee has been exposed to a
potentially hazardous amount of MDA in an emergency situation under paragraph (e) of this section,
the employer shall provide medical examinations in accordance with paragraphs (n)(3) (i) and (ii) of
this section. If the results of liver function testing indicate an abnormality, the employee shall be
removed in accordance with paragraph (n)(9) of this section. Repeat liver function tests shall be
conducted on the advice of the physician. If the results of the tests are normal, tests must be
repeated two to three weeks from the initial testing. If the results of the second set of tests are
normal and on the advice of the physician, no additional testing is required.
(5) Additional examinations. Where the employee develops signs and symptoms associated with
exposure to MDA, the employer shall provide the employee with an additional medical examination
including liver function tests. Repeat liver function tests shall be conducted on the advice of the
physician. If the results of the tests are normal, tests must be repeated two to three weeks from the
initial testing. If the results of the second set of tests are normal and on the advice of the physician,
no additional testing is required.
(6) Multiple physician review mechanism.
(i)

If the employer selects the initial physician who conducts any medical examination or
consultation provided to an employee under this section, and the employee has signs or
symptoms of occupational exposure to MDA (which could include an abnormal liver function
test), and the employee disagrees with the opinion of the examining physician, and this opinion
could affect the employee's job status, the employee may designate an appropriate and
mutually acceptable second physician:
(A) To review any findings, determinations or recommendations of the initial physician; and
(B) To conduct such examinations, consultations, and laboratory tests as the second
physician deems necessary to facilitate this review.

(ii) The employer shall promptly notify an employee of the right to seek a second medical opinion
after each occasion that an initial physician conducts a medical examination or consultation
pursuant to this section. The employer may condition its participation in, and payment for, the

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29 CFR 1926.60(n)(6)(ii)(A)

multiple physician review mechanism upon the employee doing the following within fifteen (15)
days after receipt of the foregoing notification, or receipt of the initial physician's written
opinion, whichever is later:
(A) The employee informing the employer that he or she intends to seek a second medical
opinion, and
(B) The employee initiating steps to make an appointment with a second physician.
(iii) If the findings, determinations, or recommendations of the second physician differ from those
of the initial physician, then the employer and the employee shall assure that efforts are made
for the two physicians to resolve any disagreement.
(iv) If the two physicians have been unable to quickly resolve their disagreement, then the employer
and the employee through their respective physicians shall designate a third physician:
(A) To review any findings, determinations, or recommendations of the prior physicians; and
(B) To conduct such examinations, consultations, laboratory tests, and discussions with the
prior physicians as the third physician deems necessary to resolve the disagreement of
the prior physicians.
(v) The employer shall act consistent with the findings, determinations, and recommendations of
the second physician, unless the employer and the employee reach a mutually acceptable
agreement.
(7) Information provided to the examining physician.
(i)

The employer shall provide the following information to the examining physician:
(A) A copy of this regulation and its appendices;
(B) A description of the affected employee's duties as they relate to the employee's potential
exposure to MDA;
(C) The employee's current actual or representative MDA exposure level;
(D) A description of any personal protective equipment used or to be used; and
(E) Information from previous employment related medical examinations of the affected
employee.

(ii) The employer shall provide the foregoing information to a second physician under this section
upon request either by the second physician, or by the employee.
(8) Physician's written opinion.
(i)

For each examination under this section, the employer shall obtain, and provide the employee
with a copy of, the examining physician's written opinion within 15 days of its receipt. The
written opinion shall include the following:
(A) The occupationally pertinent results of the medical examination and tests;
(B) The physician's opinion concerning whether the employee has any detected medical
conditions which would place the employee at increased risk of material impairment of
health from exposure to MDA;

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29 CFR 1926.60(n)(8)(i)(C)

(C) The physician's recommended limitations upon the employee's exposure to MDA or upon
the employee's use of protective clothing or equipment and respirators; and
(D) A statement that the employee has been informed by the physician of the results of the
medical examination and any medical conditions resulting from MDA exposure which
require further explanation or treatment.
(ii) The written opinion obtained by the employer shall not reveal specific findings or diagnoses
unrelated to occupational exposures.
(9) Medical removal —
(i)

Temporary medical removal of an employee —
(A) Temporary removal resulting from occupational exposure. The employee shall be removed
from work environments in which exposure to MDA is at or above the action level or where
dermal exposure to MDA may occur, following an initial examination (paragraph (n)(2) of
this section), periodic examinations (paragraph (n)(3) of this section), an emergency
situation (paragraph (n)(4) of this section), or an additional examination (paragraph (n)(5)
of this section) in the following circumstances:
(1) When the employee exhibits signs and/or symptoms indicative of acute exposure to
MDA; or
(2) When the examining physician determines that an employee's abnormal liver function
tests are not associated with MDA exposure but that the abnormalities may be
exacerbated as a result of occupational exposure to MDA.
(B) Temporary removal due to a final medical determination.
(1) The employer shall remove an employee from work having an exposure to MDA at or
above the action level or where the potential for dermal exposure exists on each
occasion that a final medical determination results in a medical finding,
determination, or opinion that the employee has a detected medical condition which
places the employee at increased risk of material impairment to health from
exposure to MDA.
(2) For the purposes of this section, the phrase “final medical determination” shall mean
the outcome of the physician review mechanism used pursuant to the medical
surveillance provisions of this section.
(3) Where a final medical determination results in any recommended special protective
measures for an employee, or limitations on an employee's exposure to MDA, the
employer shall implement and act consistent with the recommendation.

(ii) Return of the employee to former job status.
(A) The employer shall return an employee to his or her former job status:
(1) When the employee no longer shows signs or symptoms of exposure to MDA, or
upon the advice of the physician.

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29 CFR 1926.60(n)(9)(ii)(A)(2)

(2) When a subsequent final medical determination results in a medical finding,
determination, or opinion that the employee no longer has a detected medical
condition which places the employee at increased risk of material impairment to
health from exposure to MDA.
(B) For the purposes of this section, the requirement that an employer return an employee to
his or her former job status is not intended to expand upon or restrict any rights an
employee has or would have had, absent temporary medical removal, to a specific job
classification or position under the terms of a collective bargaining agreement.
(iii) Removal of other employee special protective measure or limitations. The employer shall remove
any limitations placed on an employee or end any special protective measures provided to an
employee pursuant to a final medical determination when a subsequent final medical
determination indicates that the limitations or special protective measures are no longer
necessary.
(iv) Employer options pending a final medical determination. Where the physician review mechanism
used pursuant to the medical surveillance provisions of this section, has not yet resulted in a
final medical determination with respect to an employee, the employer shall act as follows:
(A) Removal. The employer may remove the employee from exposure to MDA, provide special
protective measures to the employee, or place limitations upon the employee, consistent
with the medical findings, determinations, or recommendations of the physician who has
reviewed the employee's health status.
(B) Return. The employer may return the employee to his or her former job status, and end any
special protective measures provided to the employee, consistent with the medical
findings, determinations, or recommendations of any of the physicians who have reviewed
the employee's health status, with two exceptions:
(1) If the initial removal, special protection, or limitation of the employee resulted from a
final medical determination which differed from the findings, determinations, or
recommendations of the initial physician; or
(2) The employee has been on removal status for the preceding six months as a result of
exposure to MDA, then the employer shall await a final medical determination.
(v) Medical removal protection benefits —
(A) Provisions of medical removal protection benefits. The employer shall provide to an
employee up to six (6) months of medical removal protection benefits on each occasion
that an employee is removed from exposure to MDA or otherwise limited pursuant to this
section.
(B) Definition of medical removal protection benefits. For the purposes of this section, the
requirement that an employer provide medical removal protection benefits means that the
employer shall maintain the earnings, seniority, and other employment rights and benefits
of an employee as though the employee had not been removed from normal exposure to
MDA or otherwise limited.

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29 CFR 1926.60(n)(9)(v)(C)

(C) Follow-up medical surveillance during the period of employee removal or limitations. During
the period of time that an employee is removed from normal exposure to MDA or
otherwise limited, the employer may condition the provision of medical removal protection
benefits upon the employee's participation in follow-up medical surveillance made
available pursuant to this section.
(D) Workers' compensation claims. If a removed employee files a claim for workers'
compensation payments for a MDA-related disability, then the employer shall continue to
provide medical removal protection benefits pending disposition of the claim. To the
extent that an award is made to the employee for earnings lost during the period of
removal, the employer's medical removal protection obligation shall be reduced by such
amount. The employer shall receive no credit for workers' compensation payments
received by the employee for treatment-related expenses.
(E) Other credits. The employer's obligation to provide medical removal protection benefits to
a removed employee shall be reduced to the extent that the employee receives
compensation for earnings lost during the period of removal either from a publicly or
employer-funded compensation program, or receives income from employment with any
employer made possible by virtue of the employee's removal.
(F) Employees who do not recover within the 6 months of removal. The employer shall take the
following measures with respect to any employee removed from exposure to MDA:
(1) The employer shall make available to the employee a medical examination pursuant
to this section to obtain a final medical determination with respect to the employee;
(2) The employer shall assure that the final medical determination obtained indicates
whether or not the employee may be returned to his or her former job status, and, if
not, what steps should be taken to protect the employee's health;
(3) Where the final medical determination has not yet been obtained, or once obtained
indicates that the employee may not yet be returned to his or her former job status,
the employer shall continue to provide medical removal protection benefits to the
employee until either the employee is returned to former job status, or a final medical
determination is made that the employee is incapable of ever safely returning to his
or her former job status; and
(4) Where the employer acts pursuant to a final medical determination which permits the
return of the employee to his or her former job status despite what would otherwise
be an unacceptable liver function test, later questions concerning removing the
employee again shall be decided by a final medical determination. The employer
need not automatically remove such an employee pursuant to the MDA removal
criteria provided by this section.
(vi) Voluntary removal or restriction of an employee. Where an employer, although not required by
this section to do so, removes an employee from exposure to MDA or otherwise places
limitations on an employee due to the effects of MDA exposure on the employee's medical
condition, the employer shall provide medical removal protection benefits to the employee
equal to that required by paragraph (n)(9)(v) of this section.
(o) Recordkeeping —

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29 CFR 1926.60(o)(1)

(1) Objective data for exempted operations.
(i)

Where the employer has relied on objective data that demonstrate that products made from or
containing MDA are not capable of releasing MDA or do not present a dermal exposure
problem under the expected conditions of processing, use, or handling to exempt such
operations from the initial monitoring requirements under paragraph (f)(2) of this section, the
employer shall establish and maintain an accurate record of objective data reasonably relied
upon in support of the exemption.

(ii) The record shall include at least the following information:
(A) The product qualifying for exemption;
(B) The source of the objective data;
(C) The testing protocol, results of testing, and/or analysis of the material for the release of
MDA;
(D) A description of the operation exempted and how the data support the exemption; and
(E) Other data relevant to the operations, materials, processing, or employee exposures
covered by the exemption.
(iii) The employer shall maintain this record for the duration of the employer's reliance upon such
objective data.
(2) Historical monitoring data.
(i)

Where the employer has relied on historical monitoring data that demonstrate that exposures
on a particular job will be below the action level to exempt such operations from the initial
monitoring requirements under paragraph (f)(2) of this section, the employer shall establish
and maintain an accurate record of historical monitoring data reasonably relied upon in support
of the exception.

(ii) The record shall include information that reflect the following conditions:
(A) The data upon which judgments are based are scientifically sound and were collected
using methods that are sufficiently accurate and precise;
(B) The processes and work practices that were 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;
(C) 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;
(D) Environmental conditions prevailing when the historical monitoring data were obtained are
the same as those on the job for which initial monitoring will not be performed; and
(E) Other data relevant to the operations, materials, processing, or employee exposures
covered by the exception.
(iii) The employer shall maintain this record for the duration of the employer's reliance upon such
historical monitoring data.
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29 CFR 1926.60(o)(3)

(3) The employer may utilize the services of competent organizations such as industry trade
associations and employee associations to maintain the records required by this section.
(4) Exposure measurements.
(i)

The employer shall keep an accurate record of all measurements taken to monitor employee
exposure to MDA.

(ii) This record shall include at least the following information:
(A) The date of measurement;
(B) The operation involving exposure to MDA;
(C) Sampling and analytical methods used and evidence of their accuracy;
(D) Number, duration, and results of samples taken;
(E) Type of protective devices worn, if any; and
(F) Name and exposure of the employees whose exposures are represented.
(iii) The employer shall maintain this record for at least thirty (30) years, in accordance with 29 CFR
1910.33.
(5) Medical surveillance.
(i)

The employer shall establish and maintain an accurate record for each employee subject to
medical surveillance by paragraph (n) of this section, in accordance with 29 CFR 1910.33.

(ii) The record shall include at least the following information:
(A) The name of the employee;
(B) A copy of the employee's medical examination results, including the medical history,
questionnaire responses, results of any tests, and physician's recommendations.
(C) Physician's written opinions;
(D) Any employee medical complaints related to exposure to MDA; and
(E) A copy of the information provided to the physician as required by paragraph (n) of this
section.
(iii) The employer shall ensure that this record is maintained for the duration of employment plus
thirty (30) years, in accordance with 29 CFR 1910.33.
(iv) A copy of the employee's medical removal and return to work status.
(6) Training records. The employer shall maintain all employee training records for one (1) year beyond
the last date of employment.
(7) Availability.
(i)

The employer, upon written request, shall make all records required to be maintained by this
section available to the Assistant Secretary and the Director for examination and copying.

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29 CFR 1926.60(o)(7)(ii)

(ii) The employer, upon request, shall make any exposure records required by paragraphs (f) and
(n) of this section available for examination and copying to affected employees, former
employees, designated representatives, and the Assistant Secretary, in accordance with 29 CFR
1910.33(a)-(e) and (g)-(i).
(iii) The employer, upon request, shall make employee medical records required by paragraphs (n)
and (o) of this section available for examination and copying to the subject employee, anyone
having the specific written consent of the subject employee, and the Assistant Secretary, in
accordance with 29 CFR 1910.33.
(8) Transfer of records. The employer shall comply with the requirements concerning transfer of records
set forth in 29 CFR 1910.1020(h).
(p) Observation of monitoring —
(1) Employee observation. The employer shall provide affected employees, or their designated
representatives, an opportunity to observe the measuring or monitoring of employee exposure to
MDA conducted pursuant to paragraph (f) of this section.
(2) Observation procedures. When observation of the measuring or monitoring of employee exposure to
MDA requires entry into areas where the use of protective clothing and equipment or respirators is
required, the employer shall provide the observer with personal protective clothing and equipment or
respirators required to be worn by employees working in the area, assure the use of such clothing
and equipment or respirators, and require the observer to comply with all other applicable safety and
health procedures.
(q) Appendices. The information contained in appendices A, B, C, and D of this section is not intended, by
itself, to create any additional obligations not otherwise imposed by this standard nor detract from any
existing obligation.

Appendix A to § 1926.60—Substance Data Sheet, for 4-4′
Methylenedianiline
Note: The requirements applicable to construction work under this appendix A are identical to
those set forth in appendix A to § 1910.1050 of this chapter.

Appendix B to § 1926.60—Substance Technical Guidelines, MDA
Note: The requirements applicable to construction work under this appendix B are identical to
those set forth in appendix B to § 1910.1050 of this chapter.

Appendix C to § 1926.60—Medical Surveillance Guidelines for MDA
Note: The requirements applicable to construction work under this appendix C are identical to
those set forth in appendix C to § 1910.1050 of this chapter.

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29 CFR 1926.60(q)

Appendix D to § 1926.60—Sampling and Analytical Methods for MDA
Monitoring and Measurement Procedures
Note: The requirements applicable to construction work under this appendix D are identical to
those set forth in appendix D to § 1910.1050 of this chapter.
[57 FR 35681, Aug. 10, 1992, as amended at 57 FR 49649, Nov. 3, 1992; 61 FR 5510, Feb. 13, 1996; 61 FR 31431, June 20, 1996; 63
FR 1296, Jan. 8, 1998; 69 FR 70373, Dec. 6, 2004; 70 FR 1143, Jan. 5, 2005; 71 FR 16674, Apr. 3, 2006; 71 FR 50191, Aug. 24, 2006;
73 FR 75588, Dec. 12, 2008; 76 FR 33611, June 8, 2011; 77 FR 17889, Mar. 26, 2012]

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