Subpart Z
The airborne permissible exposure limit for MDA is 10 parts per billion (10 ppb) as an 8-hour time-weighted average (TWA), and the action level is 5 ppb. See the Substance Data Sheet for MDA in Appendix A to 1910.1050 for these values.
No — eye contact and skin contact with MDA are not permitted. The Substance Data Sheet in Appendix A to 1910.1050 explicitly states that dermal exposure (including eyes and skin) must be prevented.
Short-term exposure to MDA may cause fever, chills, loss of appetite, vomiting, jaundice, and irritation of skin, eyes, and mucous membranes; sensitization can also occur. These acute effects are listed in the Substance Data Sheet for MDA in Appendix A to 1910.1050. If you experience symptoms, inform your employer promptly.
Repeated or prolonged exposure to MDA, even at relatively low concentrations, may cause cancer and can damage the liver, kidneys, blood, and spleen. This chronic hazard is described in the Substance Data Sheet for MDA in Appendix A to 1910.1050. Employers must follow the standard to limit exposures.
An employer must provide medical examinations and laboratory tests if you are exposed at or above the action level for more than 30 days per year, or if you are exposed to liquid MDA mixtures more than 15 days per year; the initial exam must be within 60 days of the effective date of the standard and annually thereafter. These medical requirements are stated in the Substance Data Sheet in Appendix A to 1910.1050. Special exams and tests must also be made available after known or suspected toxic exposures.
If MDA is splashed into the eyes, wash the eyes for at least 15 minutes and see a doctor as soon as possible. This emergency procedure is specified in the Substance Data Sheet for MDA in Appendix A to 1910.1050. Employers must ensure prompt access to appropriate first-aid facilities.
Remove contaminated clothing immediately and wash the exposed skin with large amounts of soap and water; wash contaminated clothing before wearing it again. If leather items (like shoes) are penetrated, they should not be worn again. These steps are in the Substance Data Sheet for MDA in Appendix A to 1910.1050.
Get the exposed person to fresh air right away, apply artificial respiration if breathing has stopped, and call for medical assistance or a doctor as soon as possible. Also, never enter a vessel or confined space suspected of high MDA concentration without proper safety equipment and another person outside; use a lifeline. These emergency actions are listed in the Substance Data Sheet for MDA in Appendix A to 1910.1050.
Your employer must perform measurements representative of your exposure to MDA and you or your designated representative are entitled to observe the entire monitoring procedure and to record the results obtained. When monitoring occurs in areas requiring respirators or protective clothing, observers must be provided and wear the required protective equipment. These rights are described in the Substance Data Sheet for MDA in Appendix A to 1910.1050.
You or your representative may see records of exposure measurements upon written request to your employer, and your medical exam records can be furnished to your physician or designated representative upon your request. These record-access rights are in the Substance Data Sheet for MDA in Appendix A to 1910.1050. Employers must comply with these access procedures.
Respirators used for MDA must be approved by NIOSH under 42 CFR part 84 and cartridges/canisters must be replaced in accordance with the employer's program and the Respiratory Protection Standard, 1910.134. The MDA substance sheet in Appendix A to 1910.1050 also explains these employer obligations and training requirements.
No — you should not depend on odor to detect canister exhaustion because MDA does not have a detectable odor except at levels well above the permissible exposure limit. If you can smell MDA while wearing a respirator, you must proceed immediately to fresh air. This caution is in the MDA Substance Data Sheet in Appendix A to 1910.1050 and respirator change timing must follow 1910.134 practices.
Employers must provide thorough training to employees assigned to use a respirator, including proper use, limitations, and maintenance; training must be provided by the employer as required in the MDA substance sheet in Appendix A to 1910.1050 and the Respiratory Protection Standard, 1910.134 sets detailed training requirements and fit-testing obligations.
Where protective clothing is required to prevent skin contact with MDA, the employer must provide appropriate coveralls, aprons, gloves, face shields, or other items and must provide clean garments as necessary; contaminated clothing and shoes that are not impervious should be promptly removed and laundered or discarded, and leather penetrated by MDA must not be worn again. See the Protective Clothing and Equipment section in Appendix A to 1910.1050 for these requirements.
You must wear splashproof safety goggles in areas where liquid MDA may contact your eyes, and a face shield is required if your face could be splashed; contact lenses should not be worn where eye contact with MDA can occur. These requirements are stated in the MDA Substance Data Sheet in Appendix A to 1910.1050. Employers must provide and enforce appropriate eye and face protection.
Yes — when monitoring takes place in areas where respirators or personal protective clothing and equipment are required, the employee or representative must be provided with and must wear the protective clothing and equipment in order to observe the monitoring procedure and record results. This right is explained in the Observation of Monitoring section of Appendix A to 1910.1050.
Handle and store MDA as combustible material: avoid strong acids, anhydrides, and strong oxidizers; consult your supervisor for disposal requirements. These safe-use precautions are summarized in the Precautions for Safe Use, Handling and Storage section of Appendix A to 1910.1050. Employers should include specific handling and disposal procedures in written programs.
If you experience difficulty breathing while wearing a respirator, you can request a positive-pressure respirator from your employer. The MDA sheet in Appendix A to 1910.1050 states this and also requires employer-provided training and compliance with the Respiratory Protection Standard, 1910.134 and NIOSH approvals under 42 CFR part 84.
The employer must make special medical examinations and tests available to the exposed employee; these special exams are required after accidental exposures by ingestion, inhalation, or skin/eye contact that are known or suspected to be toxic. This requirement is in the Medical Requirements section of Appendix A to 1910.1050.
Yes — your medical examination records can be furnished to your physician or designated representative upon your request to your employer. This access right is described in the Access to Records section of Appendix A to 1910.1050. Employers must follow applicable confidentiality and recordkeeping rules.
Clothing and shoes that are not impervious should be promptly removed and decontaminated; clothing should be laundered to remove MDA or discarded, and footwear or leather articles penetrated by MDA should not be worn again. These instructions are in the Protective Clothing section of Appendix A to 1910.1050. Employers must provide procedures for cleaning or disposal.