§ 751.109 — Workplace Chemical Protection Program.

40 CFR § 751.109

• Title: Title 40: Protection of Environment
• Part: Part 751: Regulation of Certain Chemical Substances and Mixtures Under Section 6 of the Toxic Substances Control Act
• Source: eCFR (current through Apr 10, 2026)

Text

§ 751.109 Workplace Chemical Protection Program.

(a) Applicability. The provisions of this section apply to the following conditions of use of methylene chloride, including manufacturing and processing for export, except to the extent the conditions of use are prohibited by §§ 751.105 and 751.107:

(1) Manufacturing (domestic manufacture);

(2) Manufacturing (import);

(3) Processing: as a reactant;

(4) Processing: incorporation into a formulation, mixture, or reaction product;

(5) Processing: repackaging;

(6) Processing: recycling;

(7) Industrial and commercial use as a laboratory chemical;

(8) Industrial or commercial use for paint and coating removal from safety-critical, corrosion-sensitive components of aircraft and spacecraft;

(9) Industrial or commercial use as a bonding agent for solvent welding;

(10) Industrial and commercial use as a processing aid;

(11) Industrial and commercial use for plastic and rubber products manufacturing;

(12) Industrial and commercial use as a solvent that becomes part of a formulation or mixture, where that formulation or mixture will be used inside a manufacturing process, and the solvent (methylene chloride) will be reclaimed; and

(13) Disposal.

(b) Relationship to other regulations. For purposes of this section:

(1) Any provisions applying to “employee” in 29 CFR 1910.132, 1910.134, and 1910.1052 also apply equally to potentially exposed persons; and

(2) Any provisions applying to “employer” in 29 CFR 1910.132, 1910.134, and 1910.1052 also apply equally to any owner or operator for the regulated area.

(c) Exposure limits—(1) ECEL. The owner or operator must ensure that no person is exposed to an airborne concentration of methylene chloride in excess of 2 parts of methylene chloride per million parts of air (2 ppm) as an 8-hour TWA:

(i) After February 8, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(ii) After February 8, 2027, for non-Federal laboratories when using methylene chloride as a laboratory chemical;

(iii) After August 1, 2025, for other owners and operators; or

(iv) Beginning 4 months after the owner or operator introduces methylene chloride into the workplace, if methylene chloride use commences after May 5, 2025, consistent with paragraphs (d) through (f) of this section.

(2) EPA STEL. The owner or operator must ensure that no person is exposed to an airborne concentration of methylene chloride in excess of 16 parts of methylene chloride per million parts of air (16 ppm) as determined over a sampling period of 15 minutes:

(i) After February 8, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(ii) After February 8, 2027, for non-Federal laboratories when using methylene chloride as a laboratory chemical;

(iii) After August 1, 2025, for other owners and operators; or

(iv) Beginning 4 months after the owner or operator introduces methylene chloride into the workplace, if methylene chloride use commences after May 5, 2025, consistent with paragraphs (d) through (f) of this section.

(3) Regulated areas. The owner or operator must:

(i) Establish and maintain regulated areas in accordance with 29 CFR 1910.1052(e)(2) and (4) through (7):

(A) After February 8, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(B) After February 8, 2027, for non-Federal laboratories when using methylene chloride as a laboratory chemical;

(C) After August 1, 2025, for other owners and operators; or

(D) Within 3 months after the owner or operator's receipt of the results of any monitoring data consistent with paragraph (d) of this section.

(d) Exposure monitoring—(1) In general—(i) Characterization of exposures. Owners or operators must determine each potentially exposed person's exposure, without regard to respiratory protection, by either:

(A) Taking a personal breathing zone air sample of each potentially exposed person's exposure; or

(B) Taking personal breathing zone air samples that are representative of each potentially exposed person's exposure.

(ii) Representative samples. Owners or operators are permitted to consider personal breathing zone air samples to be representative of each potentially exposed person's exposure, without regard to respiratory protection, when they are taken as follows:

(A) ECEL. The owner or operator has taken one or more personal breathing zone air samples for at least one potentially exposed person in each job classification in a work area during every work shift, and the person sampled is expected to have the highest methylene chloride exposure.

(B) EPA STEL. The owner or operator has taken one or more personal breathing zone air samples which indicate the highest likely 15-minute exposures during such operations for at least one potentially exposed person in each job classification in the work area during every work shift, and the person sampled is expected to have the highest methylene chloride exposure.

(C) Exception. Personal breathing zone air samples taken during one work shift may be used to represent potentially exposed person exposures on other work shifts where the owner or operator can document that the tasks performed and conditions in the workplace are similar across shifts.

(iii) Accuracy of monitoring. Owners or operators must ensure that the methods used to perform exposure monitoring produce results that are accurate to a confidence level of 95%, and are:

(A) Within plus or minus 25% for airborne concentrations of methylene chloride above the ECEL or the EPA STEL; or

(B) Within plus or minus 35% for airborne concentrations of methylene chloride at or above the ECEL action level but at or below the ECEL.

(iv) Currency of monitoring data. Owners or operators are not permitted to rely on monitoring data that is more than 5 years old to demonstrate compliance with initial or periodic monitoring requirements for either the ECEL or the EPA STEL.

(2) Initial monitoring. (i) Unless otherwise specified in paragraphs (d)(2)(ii) or (iii) of this section, each owner or operator covered by this section must perform an initial exposure monitoring to determine each potentially exposed person's exposure:

(A) By November 9, 2026, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(B) By November 9, 2026, for non-Federal laboratories when using methylene chloride as a laboratory chemical;

(C) By May 5, 2025, for other owners and operators; or

(D) Within 30 days of the owner or operator introducing methylene chloride into the workplace, whichever is later.

(ii) An owner or operator has objective data generated within the last 5 years prior to May 8, 2024, that demonstrates to EPA that methylene chloride cannot be released in the workplace in airborne concentrations at or above the ECEL action level (1-ppm 8-hour TWA) or above the EPA STEL (16 ppm 15-minute TWA) and that the data represents the highest methylene chloride exposures likely to occur under conditions of use described in paragraph (a) of this section; or

(iii) Where potentially exposed persons are exposed to methylene chloride for fewer than 30 days per year, and the owner or operator has measurements by direct-metering devices which give immediate results and which provide sufficient information regarding exposures to determine and implement the control measures that are necessary to reduce exposures to below the ECEL action level and EPA STEL.

(3) Periodic monitoring. The owner or operator must establish an exposure monitoring program for periodic monitoring of exposure to methylene chloride in accordance with table 1.

Table 1 to Paragraph (d)(3)—Periodic Monitoring Requirements Based on Initial Exposure Monitoring Results

Air concentration condition observed during initial exposure monitoring	Periodic monitoring requirement
If the initial exposure monitoring concentration is below the ECEL action level and at or below the EPA STEL	ECEL and EPA STEL periodic monitoring at least once in every 5 years.
If the initial exposure monitoring concentration is below the ECEL action level and above the EPA STEL	ECEL periodic required at least once every 5 years, and EPA STEL periodic monitoring required every 3 months.
If the initial exposure monitoring concentration is at or above the ECEL action level and at or below the ECEL; and at or below the EPA STEL	ECEL periodic monitoring every 6 months.
If the initial exposure monitoring concentration is at or above the ECEL action level and at or below the ECEL; and above the EPA STEL	ECEL periodic monitoring every 6 months and EPA STEL periodic monitoring every 3 months.
If the initial exposure monitoring concentration is above the ECEL and below, at, or above the EPA STEL	ECEL periodic monitoring every 3 months and EPA STEL periodic monitoring every 3 months.
If 2 consecutive monitoring events have taken place at least 7 days apart that indicate that potential exposure has decreased from above the ECEL to at or below the ECEL, but at or above the ECEL action level	Transition from ECEL periodic monitoring frequency from every 3 months to every 6 months.
If 2 consecutive monitoring events have taken place at least 7 days apart that indicate that potential exposure has decreased to below the ECEL action level and at or below the EPA STEL	Transition from ECEL periodic monitoring frequency from every 6 months to once every 5 years. The second consecutive monitoring event will delineate the new date from which the next 5-year periodic exposure monitoring must occur.
If the owner or operator engages in any conditions of use described in paragraph (a) of this section and is required to monitor either the ECEL or EPA STEL in a 3-month interval, but does not engage in any of those uses for the entirety of the 3-month interval	The owner or operator may forgo the upcoming periodic monitoring event. However, documentation of cessation of use of methylene chloride must be maintained, and initial monitoring is required when the owner or operator resumes or starts any of the conditions of use described in paragraph (a) of this section.
Owner or operator engages in any conditions of use described in paragraph (a) of this section and is required to monitor the ECEL in a 6-month interval, but does not engage in any of those uses for the entirety of the 6-month interval	The owner or operator may forgo the upcoming periodic monitoring event. However, documentation of cessation of the condition(s) of use must be maintained until periodic monitoring resumes, and initial monitoring is required when the owner or operator resumes or starts any of the conditions of use described in paragraph (a) of this section.

(4) Additional monitoring. The owner or operator must conduct the exposure monitoring required by paragraph (d)(2) of this section within 30 days after any change that may reasonably be expected to introduce additional sources of exposure to methylene chloride, or otherwise result in increased exposure to methylene chloride compared to the most recent monitoring event. Examples of situations that may require additional monitoring include changes in production, process, control equipment, or work practices, or a leak, rupture, or other breakdown.

(5) Notification of monitoring results. (i) The owner or operator must inform potentially exposed persons of monitoring results within 15 working days.

(ii) This notification must include the following:

(A) Exposure monitoring results;

(B) Identification and explanation of the ECEL, ECEL Action Level, and EPA STEL;

(C) Whether the airborne concentration of methylene chloride exceeds the ECEL action level, ECEL or the EPA STEL;

(D) If the ECEL or EPA STEL is exceeded, descriptions of actions taken by the owner or operator to reduce exposure in accordance with paragraph (e)(1)((i) of this section;

(E) Explanation of any required respiratory protection provided in accordance with as paragraphs (e)(1)(ii) and (f) of this section;

(F) Quantity of methylene chloride in use at the time of monitoring;

(G) Location of methylene chloride use at the time of monitoring;

(H) Manner of methylene chloride use at the time of monitoring; and

(I) Identified releases of methylene chloride.

(iii) Notice must be provided in plain language writing, in a language that the person understands, to each potentially exposed person or posted in an appropriate and accessible location outside the regulated area with an English-language version and a non-English language version representing the language of the largest group of workers who do not read English.

(6) Observation of monitoring. (i) The owner or operator must provide affected potentially exposed persons an opportunity to observe exposure monitoring conducted in accordance with this paragraph (d) that is representative of the potentially exposed person's exposure.

(ii) The owner or operator must ensure that potentially exposed persons are provided with personal protective equipment appropriate for the observation of monitoring.

(e) ECEL control procedures and plan—(1) Methods of compliance. (i) The owner or operator must institute one or a combination of elimination, substitution, engineering controls, work practices, or administrative controls to reduce exposure to or below the ECEL and EPA STEL except to the extent that the owner or operator can demonstrate that such controls are not feasible:

(A) By May 10, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(B) By May 10, 2027, for non-Federal laboratories using methylene chloride as a laboratory chemical;

(C) By October 30, 2025, for other owners and operators; or

(D) Within 7 months of the owner or operator introducing methylene chloride into the workplace.

(ii) If the feasible controls, required by paragraph (e)(1)(i) of this section that can be instituted do not reduce exposures for potentially exposed persons to or below the ECEL or EPA STEL, then the owner or operator must use such controls to reduce exposure to the lowest levels achievable by these controls and must supplement those controls with the use of respiratory protection that complies with the requirements of paragraph (f) of this section to reduce exposures to or below the ECEL or EPA STEL.

(iii) Where an owner or operator cannot demonstrate exposure below the ECEL, including through the use of all feasible engineering controls, work practices, or administrative controls as described in paragraph (e)(1)(i) of this section, and, has not demonstrated that it has appropriately supplemented with respiratory protection that complies with the requirements of paragraphs (e)(1)(ii) and (f) of this section, this will constitute a failure to comply with the ECEL.

(iv) For the Department of Defense and Federal contractors acting for or on behalf of the Department of Defense, in the event that ongoing or planned construction is necessary to implement the feasible controls required by paragraph (e)(1)(i) of this section such that no one is exposed above the ECEL or EPA STEL, the deadlines in paragraph (e)(1)(i) of this section are extended to May 7, 2029. Ongoing or planned construction efforts to address exposures above the ECEL and EPA STEL must be documented in the exposure control plan required by paragraph (e)(2) of this section.

(2) Exposure control plan—(i) Exposure control plan deadlines. (A) By May 10, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(B) By May 10, 2027, for non-Federal laboratories using methylene chloride as a laboratory chemical;

(C) By October 30, 2025, for other owners and operators, the owner or operator must develop and implement an exposure control plan; or

(D) Within 7 months of the owner or operator introducing methylene chloride into the workplace.

(ii) Exposure control plan contents. The exposure control plan must include documentation of the following:

(A) Identification of exposure controls that were considered, including those that were used or not used to meet the requirements of paragraph (e)(1)(i) of this section, in the following sequence—elimination, substitution, engineering controls, and work practices and administrative controls;

(B) For each exposure control considered, a rationale for why the exposure control was selected or not selected based on feasibility, effectiveness, and other relevant considerations;

(C) A description of actions the owner or operator must take to implement the exposure controls selected, including proper installation, regular inspections, maintenance, training, or other actions;

(D) A description of regulated areas, how they are demarcated, and persons authorized to enter the regulated areas;

(E) A description of activities conducted by the owner or operator to review and update the exposure control plan to ensure effectiveness of the exposure controls, identify any necessary updates to the exposure controls, and confirm that all persons are properly implementing the exposure controls; and

(F) An explanation of the procedures for responding to any change that may reasonably be expected to introduce additional sources of exposure to methylene chloride, or otherwise result in increased exposure to methylene chloride, including procedures for implementing corrective actions to mitigate exposure to methylene chloride.

(iii) Exposure control plan requirements. (A) The owner or operator must not implement a schedule of personnel rotation as a means of compliance with the ECEL.

(B) The owner or operator must maintain the effectiveness of any controls, instituted under paragraph (e) of this section.

(C) The exposure control plan must be reviewed and updated as necessary, but at least every 5 years, to reflect any significant changes in the status of the owner or operator's approach to compliance with paragraphs (c) through (e) of this section.

(iv) Availability of exposure control plan. (A) Owners or operators must make the exposure control plan and associated records, including exposure monitoring, respiratory protection program implementation, and dermal protection program implementation records, available to potentially exposed persons.

(B) Owners or operators must notify potentially exposed persons of the availability of the plan and associated records within 30 days of the date that the exposure control plan is completed and at least annually thereafter. The notification must be provided in accordance with the requirements of paragraph (d)(5)(iii) of this section.

(C) Upon request by the potentially exposed person, the owner or operator must provide the specified records at a reasonable time, place, and manner. If the owner or operator is unable to provide the requested records within 15 days, the owner or operator must, within those 15 days, inform the potentially exposed person requesting the record(s) of the reason for the delay and the earliest date when the record can be made available.

(3) Respirator requirements. The owner or operator must supply a respirator, selected in accordance with paragraph (f) of this section, to each potentially exposed person who enters a regulated area and must ensure each potentially exposed person uses that respirator whenever methylene chloride exposures may exceed the ECEL or EPA STEL.

(f) Respiratory protection—(1) Respirator conditions. The owner or operator must provide respiratory protection to all potentially exposed persons in the regulated area as outlined in paragraph (c)(3) of this section, and according to the provisions outlined in 29 CFR 1910.134(a) through (l) (except 29 CFR 1910.134(d)(1)(iii)) and as specified in this paragraph (f) for potentially exposed persons exposed to methylene chloride in concentrations above the ECEL or the EPA STEL. For the purpose of this paragraph (f), the maximum use concentration (MUC) as used in 29 CFR 1910.134 must be calculated by multiplying the assigned protection factor (APF) specified for a respirator by the ECEL or EPA STEL:

(i) After February 8, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(ii) After February 8, 2027, for non-Federal laboratories using methylene chloride as a laboratory chemical;

(iii) After August 1, 2025, for other owners and operators; or

(iv) Within 3 months after the owner or operator's receipt of the results of any exposure monitoring as described in paragraph (d) of this section.

(2) Respirator selection criteria. The type of respiratory protection that regulated entities must select and provide to potentially exposed persons in accordance with 29 CFR 1910.1052(g)(3)(i), is directly related to the monitoring results, as follows:

(i) If the measured exposure concentration is at or below the ECEL or EPA STEL: no respiratory protection is required.

(ii) If the measured exposure concentration is above 2 ppm and less than or equal to 50 ppm: the respirator protection required is any NIOSH Approved® supplied-air respirator (SAR) or airline respirator in a continuous-flow mode equipped with a loose-fitting facepiece or helmet/hood (APF 25).

(iii) If the measured exposure concentration is above 50 ppm and less than or equal to 100 ppm the respirator protection required is:

(A) Any NIOSH Approved® Supplied-Air Respirator (SAR) or airline respirator in a demand mode equipped with a full facepiece (APF 50); or

(B) Any NIOSH Approved® Self-Contained Breathing Apparatus (SCBA) in demand-mode equipped with a full facepiece or helmet/hood (APF 50).

(iv) If the measured exposure concentration is unknown or at any value above 100 ppm and up to 2,000 ppm the respirator protection required is:

(A) Any NIOSH Approved® Supplied-Air Respirator (SAR) or airline respirator in a continuous-flow mode equipped with a full facepiece or certified helmet/hood that has been tested to demonstrate performance at a level of a protection of APF 1,000 or greater. (APF 1,000); or

(B) Any NIOSH Approved® Supplied-Air Respirator (SAR) or airline respirator in pressure-demand or other positive-pressure mode equipped with a full facepiece and an auxiliary self-contained air supply (APF 1,000); or

(C) Any NIOSH Approved® Self-Contained Breathing Apparatus (SCBA) in a pressure-demand or other positive-pressure mode equipped with a full facepiece or certified helmet/hood (APF 10,000).

(3) Minimal respiratory protection. Requirements outlined in paragraph (e)(2) of this section represent the minimum respiratory protection requirements, such that any respirator affording a higher degree of protection than the required respirator may be used.

(g) Dermal protection. (1) The owner or operator must require the donning of gloves that are chemically resistant to methylene chloride with activity-specific training where dermal contact with methylene chloride is possible, after application of the requirements in paragraph (e) of this section, in accordance with the NIOSH hierarchy of controls:

(i) After February 8, 2027, for Federal agencies, Federal contractors acting for or on behalf of the Federal Government;

(ii) After February 8, 2027, for non-Federal laboratories using methylene chloride as a laboratory chemical; or

(iii) After August 1, 2025, for other owners and operators.

(2) Owners or operators must minimize and protect potentially exposed persons from dermal exposure in accordance with 29 CFR 1910.1052(h) and (i).

(h) Training. Owners or operators must provide training in accordance with 29 CFR 1910.1052(l)(1) through (6) to potentially exposed persons prior to or at the time of initial assignment to a job involving potential exposure to methylene chloride. In addition, if respiratory protection or PPE must be worn within a regulated area, owners or operators must provide training in accordance with 29 CFR 1910.132(f) to potentially exposed persons within that regulated area.

[89 FR 39297, May 8, 2024, as amended at 90 FR 50898, Nov. 13, 2025]