Chemical Hygiene Plan

Scope and Application
Roles and Responsibilities
Chemical and Hazard Identification
Standard Operating Procedures
Controlling Chemical Exposure
Fume Hood Performance Evaluation
Information and Training
Prior Approval for Laboratory Procedures
Medical Examinations and Consultations
Particularly Hazardous Substances
Laboratory Inspections and Audits
MAE  Department Facility Systems
For More Information

This Chemical Hygiene Plan was developed in response to the federal Occupational Health and Safety Administration (OSHA) regulation, Occupational Exposures to Hazardous Chemicals in the Laboratory (29 CFR 1910.1450), commonly referred to as the "Laboratory Standard".

The purpose of the Chemical Hygiene Plan is to provide guidelines for prudent work practices and procedures for the laboratory use of chemicals, and to protect laboratory workers from the potential health hazards of the chemicals they encounter in the workplace.

All laboratory workers must be made aware of this plan. New employees should review the plan and receive safety training before beginning work with hazardous chemicals. The plan is available to all laboratory workers at all times.

Scope and Application

The Laboratory Standard covers employees who work with hazardous chemicals in laboratories. At Princeton University, this program applies to all individuals working with hazardous chemicals in science and engineering laboratories. Work with hazardous chemicals outside of laboratories is covered by the Hazard Communication Standard (29 CFR 1910.1200). See Section C2 of the Princeton University Health and Safety Guide for more information about Hazard Communication.

Roles and Responsibilities

Department Safety Manager and Chemical Hygiene Officer

Michael Vocaturo is the Department Safety Manager and Professor Michael Littman is the Chemical Hygiene Officer for the Mechanical and Aerospace Engineering Department (MAE).  They are responsible for developing and implementing this Chemical Hygiene Plan and for the following:

  • Review and update the Chemical Hygiene Plan at least annually.
  • Investigate accidents and chemical exposures within the department.
  • Act as a liaison between the MAE Department and the Environmental Health and Safety Office (EHS) for laboratory safety issues.
  • Maintain records of training, exposure monitoring and medical examinations.
  • Ensure laboratory workers receive chemical and procedure-specific training.
  • Approve laboratory workers return to work following a chemical exposure requiring medical consultation.
  • Review and approve use of particularly hazardous substances.
  • Principal Investigators
  • Ensure laboratory workers attend general lab safety training given by EHS.
  • Ensure laboratory workers understand how to work with chemicals safely. Provide chemical and procedure-specific training, as needed.
  • Provide laboratory workers with appropriate engineering controls and personal protective equipment needed to work safely with hazardous materials. Ensure such equipment is used correctly.
  • Ensure laboratory workers complete and submit Particularly Hazardous Substance Use Approval forms and submit them for approval before using any particularly hazardous substance.
  • Review and approve work with particularly hazardous substances.
  • Environmental Health and Safety (EHS)
  • Provide consultation for safe work practices for hazardous chemicals
  • Provide general training.
  • Provide safe working guidelines for laboratory workers through the EHS web page.
  • Inspect fume hoods annually
  • Develop and maintain the Laboratory Safety Manual
  • Conduct exposure monitoring, as needed.
  • Audit the departmental program periodically.
  • Review the model Chemical Hygiene Plan at least annually
  • Conduct limited laboratory safety inspections annually
  • Laboratory Worker
  • Attend laboratory safety training.
  • Review the Chemical Hygiene Plan.
  • Follow procedures and laboratory practices outlined in the Chemical Hygiene Plan and the Laboratory Safety Manual
  • Adhere to all University and departmental safety policies and procedures and comply with safety directives issued by supervisors and principal investigators.
  • Use engineering controls and personal protective equipment, as appropriate.
  • Report all incidents, accidents and potential chemical exposures to the principal investigator and the Chemical Hygiene Officer.
  • Document specific operating procedures for work with particularly hazardous substances, including carcinogens, reproductive toxins and chemicals with high acute toxicity.

    Chemical and Hazard Identification

    Chemical manufacturers or distributors perform an assessment of the physical and health hazards of each chemical they produce. This information is included in a material safety data sheet (MSDS) and, in part, on container labels.

    The manufacturer's label should be kept intact. When a chemical is transferred to another container for storage, the new containers should be labeled with the name of the product, the chemical constituents and hazard warnings.

    Material safety data sheets received with chemical shipments must be maintained.  Laboratory personnel who receive an MSDS should keep the original MSDS in the laboratory.  MSDSs for most laboratory chemicals may be found through the EHS web page.

    Additional chemical safety resources are available through the EHS Lab Safety web page.

    Standard Operating Procedures

    The Laboratory Safety Manual on the EHS web page provides general principles for working safely with hazardous chemicals. Principal investigators, laboratory managers and laboratory workers are encouraged to develop and implement more detailed guidelines for specific operations and chemicals in their laboratories.

    Controlling Chemical Exposure

    The following criteria are used to determine and implement control measures to reduce exposures to hazardous chemicals.

    Exposure Monitoring

    Exposure monitoring is conducted by EHS upon request if there is reason to believe that exposure levels for a particular substance may routinely exceed either the action level or the permissible exposure limit set forth by OSHA. Individuals may contact EHS directly at x8-5294 or notify the Department Safety Manager, Michael Vocaturo.

    Results of the monitoring will be made available by EHS to the individual(s) monitored, their supervisors, and the Chemical Hygiene Officer within 15 working days of the receipt of analytical results.

    Based on the monitoring results, periodic monitoring may be scheduled at the discretion of EHS, in accordance with applicable federal, state and local regulations.

    Control Measures

    Engineering controls are the primary means of control for exposure to hazardous chemicals. Local ventilation, including fume hoods, ducted biosafety cabinets, glove boxes, vented storage cabinets, and vented canopies are the most common types of engineering controls. Upon request, EHS provides assistance in determining the appropriate type of engineering controls for specific operations.

    Protective equipment, including gloves, face shields, safety glasses, safety goggles, lab coats and aprons, are used when engineering controls are not sufficient to adequately control exposure. Specifically, this equipment is used to prevent exposure to the skin or eyes. Personal protective equipment is carefully selected to ensure that it is compatible with the chemicals used. Information about selection of appropriate protective equipment is available in the Laboratory Safety Manual.

    When feasible engineering controls are not adequate to reduce inhalation exposure to acceptable levels, a respirator may be used to minimize exposure to airborne contaminants. Use of a respirator is subject to approval by EHS and must be in accordance with the University Respiratory Protection Policy. See Section C4 of the Princeton University Health and Safety Guide for more information.

    Administrative Controls

    It may be necessary to supplement engineering controls and protective equipment with administrative controls, such as restricting access to an area, restricting use of particular chemicals to a limited group of people, or limiting the length of exposure.

    Fume Hood Performance Evaluation

    Laboratory fume hoods are evaluated at least annually by EHS technical staff. An inspection sticker is affixed to each hood to document the evaluation and to provide information to the hood user regarding the measured performance of the hood. Each fume hood is equipped with at least one type of continuous monitoring device designed to provide the user with current information on the operational status of the hood. Section 6.2 of the Laboratory Safety Manual has more information about the safe operation of laboratory hoods and the hood survey program.

    In the event that a hood does not appear to be operating properly, hood users may contact EHS at x8-5294 for a performance evaluation. Routine maintenance and repairs of fume hoods are conducted by Special Facilities.

    Hood users may route requests for hood repair directly to Eric Litostansky of Special Facilities at 258-4565.  EHS does not initiate maintenance or ensure that it is completed. Upon request, EHS will re-inspect the fume hood following maintenance or repairs.

    Information and Training

    All laboratory workers must receive laboratory safety training when they are first assigned to a work area where hazardous chemicals are present and before assignments involving new exposure situations. General laboratory safety training is provided by EHS. More specific training for particular materials or operations in a particular work area is provided by the Principal Investigators, laboratory staff and teaching assistants.

    EHS Laboratory Safety Training

    EHS provides Laboratory Safety Training sessions each semester and by request. Contact Brandon Chance at x8-7882 or Kyle Angjelo at x8-2711 to request a training session.

    The general training offered by EHS covers the following topics:

      1. An overview of the OSHA Laboratory Standard. Full text of the standard is available on the web at
      2. The content and availability of the Chemical Hygiene Plan and Laboratory Safety Manual
      3. The availability of material safety data sheets and how to use them.
      4. An explanation of permissible exposure limits for chemicals
      5. An overview of methods to recognize hazards, how to evaluate hazards, and common methods to prevent and control exposure
      6. The use, function and selection of personal protective equipment
      7. Emergency procedures for fire, injury, chemical exposure, and chemical spill situations
      8. Chemical waste disposal procedures at Princeton University.
    Departmental Information and Training

    Each laboratory worker must be made aware of the following information:

  • Location of the Chemical Hygiene Plan: The Chemical Hygiene Plan for the MAE is accessible in each laboratory, in Michael Vocaturo's office (room J207 E-Quad), and on the web.
  • Nature and potential health and safety risks of specific hazardous substances used by the laboratory worker. Each Principal Investigator ensures that each individual working in his or her laboratory understands the hazards of and how to properly handle the materials in the laboratory. The PI maintains relevant files in the laboratory.
  • Proper handling, under all circumstances, of hazardous substances used in the laboratory.
  • Location and availability of reference materials, including material safety data sheets (MSDSs) for hazardous chemicals used or stored in the laboratory.
  • Training Records

    EHS maintains a database of attendance for training sessions given by EHS. Attendance lists are sent to the Chemical Hygiene Officer upon request. The MAE attendance records for EHS training sessions and in-house training are maintained by the School of Engineering and Applied Sciences.

    Prior Approval for Laboratory Procedures

    Individuals planning to use Particularly Hazardous Substances, as described later in this document, must complete a Particularly Hazardous Substance Use Approval Form and have it approved by the Principal Investigator or supervisor and the departmental Chemical Hygiene Officer prior to their initial use of the substance. Forms are available from the Chemical Hygiene Officer and can be dowloaded from the web.

    Responsibility for determining whether a chemical is a Particularly Hazardous Substance rests jointly with the supervisor and the individual planning to use the substance.

    Peer Review

    Any laboratory worker who is concerned about safety considerations involving a particular apparatus, experiment or chemical should contact Michael Littman by e-mail at  If necessary, the Chemical Hygiene Officer will coordinate a peer review.

    Medical Examinations and Consultations

    Medical Consultation Policy

    Laboratory workers should seek medical attention from University Health Services at McCosh under the following conditions:

      1. If the individual experiences signs or symptoms associated with a hazardous chemical to which he or she may have been exposed in the laboratory
      2. Where exposure monitoring reveals an exposure level routinely above the OSHA action level or permissible exposure limit
      3. Whenever a spill, leak, explosion or other occurrence results in the likelihood of a hazardous exposure to a laboratory worker
    All medical exams will be performed by or under the direction of University Health Services at McCosh staff and provided at no cost to the worker, without loss of pay.

    Incident Reporting

    In the event of any incident that results in a possible overexposure to a chemical, regardless of whether any signs or symptoms of exposure are noted or whether the laboratory worker seeks medical attention, the laboratory worker should complete a Report of Possible Chemical Overexposure Form.  Forms may be obtained on-line or from the department office.  The form must be submitted to Michael Vocaturo and copies forwarded to EHS and Occupational Medicine at McCosh Health Center. Completed forms are retained by Michael Vocaturo.

    Medical Consultation Procedure

    In an emergency situation, the laboratory worker should immediately be taken to McCosh Health Center or Princeton Medical Center, as appropriate. Public Safety may be contacted at 911 for transportation. For a non-emergency exposure situation, the laboratory worker or supervisor should contact McCosh Health Center at x8-5035 to schedule an appointment.

    The laboratory worker, supervisor, or Chemical Hygiene Officer must provide the physician with the identity of the hazardous chemicals encountered in the workplace and the conditions by which the worker was exposed. If available, the material safety data sheet or other safety information resource should be provided to the physician.

    The examining physician will submit a written opinion to the laboratory worker and the Chemical Hygiene Officer using the Medical Consultation Form. The opinion shall not reveal any specific findings or diagnoses unrelated to the occupational exposure. The opinion will include the following information:

      1. Recommendations for further medical follow-up;
      2. Results of the medical examination, and any test results;
      3. Any medical condition revealed during the examination that may place the worker at increased risk as a result of exposure to the hazardous chemical found in the workplace.
    Based on the physician's opinion, the Chemical Hygiene Officer shall approve the individual's return to work.

    Particularly Hazardous Substances

    Particularly hazardous substances are defined to include select carcinogens, reproductive toxins and substances that have a high degree of acute toxicity (such as cyanides and dimethyl mercury).

    Select carcinogens include any substance that is included on any of the following lists of carcinogens:

    Reproductive toxin includes any chemical that may affect the reproductive capabilities including chromosomal damage (mutations) and effects on fetuses (teratogenesis).

    High acute toxicity includes any chemical that falls within any of the following categories:

    A list of the more commonly used particularly hazardous substances is available in the Laboratory Safety Manual, however, this list is not exhaustive. Consult the product MSDS or contact EHS for assistance in determining whether a substance is classified as particularly hazardous.

    Before using a particularly hazardous substance, an individual must:

      1. Complete a Particularly Hazardous Substance Use Approval Form. This form is available from the department office or  can be downloaded.
      2. Submit the completed form to their supervisor or Principal Investigator for approval.
      3. Submit the approved form to Michael Littman for approval.
      4. Post the area where the substance will be used with a Designated Area sign, available from the departmental Chemical Hygiene Officer or EHS or can be downloaded..
      5. Follow the procedures outlined in the approved form and in the Laboratory Safety Manual.
    The Particularly Hazardous Substance Use Approval Form provides documentation of the specific standard operating procedure for use of the substance. These procedures include the use of containment devices and personal protective equipment, decontamination procedures and procedures for safe removal of contaminated waste.

    Laboratory Inspections and Audits

    Laboratory Inspections

    EHS technicians conduct a limited laboratory inspection at the time of the fume hood performance evaluation. A summary of the inspection results and copies of the inspection forms are provided to the Chemical Hygiene Officer.

    The Chemical Hygiene Officer may conduct additional laboratory inspections.

    Fire Extinguishers

    Fire extinguisher are inspected monthly by Building Services personnel. Should a fire extinguisher be used or if the inspection is out-of-date, e-mail or call Otto Meilick at x8-0566.

    Safety Showers and Eyewash Fountains

    Special Facilities staff inspect all safety showers and eyewash fountains every six months. Contact Eric Litostansky at 258-4565 if inspection is out-of-date or for any questions.

    Self-Contained Breathing Apparatus

    If self-contained breathing apparatus (SCBA) is used, contact EHS at x8-5294 immediately for decontamination and refilling.  SEAS staff, Joe Laskow, inspects SCBA monthly, with the exception of the units in Professor Choueiri' s laboratory, which are inspected by Robert Sorenson .  Contact Amy Lewis at 258-8688 with any questions.

    Mechanical and Aerospace Engineering Department Facility Systems

    There are several types of alarms in MAE:

    Fire Alarm
    The fire alarm has a distinctive sound consisting of a loud, constant horn that sounds throughout the School of Engineering and Applied Sciences, regardless of the location of the alarm sensor or pull box station.  The fire alarm is activated by smoke sensor or manual pull box stations.  The system is monitored by Public Safety and serviced by the University Alarm Shop.

    If the fire alarm sounds, immediately leave the building and report to the designated area assigned to the laboratory.  See the SEAS Emergency Action Plan for more details.

    Fume Hood Alarms
    Some fume hoods in MAE are equipped with alarms.  The alarm sounds are distinctively different from the fire alarm.  Some alarms sound when the fume hood exhaust falls below a set percentage (e.g., 70% of the expected performance).  Fume hoods in the J wing are of this type.  In the event of this type of alarm, lower the sash and contact Eric Litostansky at 258-4565 for maintenance.

    Some fume hoods alarm when the horizontal sash is above or below a fixed level.  These are controlled in real time by the laboratory worker.

    Hydrocarbon Alarms
    Some laboratories in MAE are equipped with alarms warning of explosive gas mixtures.  The alarm sounds are distinctly different from the fire alarm.  These alarms sound when the gas mixture is some percentage of the lean explosive gas limit, typically 30% (warning) and 60% (emergency, evacuate area).

    Vacuum Systems
    The central vacuum system serving the School of Engineering and Applied Sciences is located in the basement of the building, in a mechanical room.  Their model numbers and operating instructions are recorded and maintained by the Special Facilities Maintenance group serving SEAS.

    Protection from contamination is achieved by water trapping vapors at the basement location.  However, since odors still occur at times in that location, users of the system are required to cold trap at the usage source.  The vacuum systems provide vacuum in the range of 17-25 inches mercury.

    Types of Fume Hoods

    The fume hoods in MAE are bypass hoods with a vertical sash, equipped with magnehelic gauges for continuous monitoring of efficiency.  Some are equipped with alarms.  Some are equipped with velocity monitors.  See the Laboratory Safety Manual for more information about these hoods.

    Facility Maintenance

    MAE personnel may obtain maintenance help in several ways:

  • Planned maintenance that is not of an immediate nature can be obtained by contacting Michael Vocaturo at 258-5236. A maintenance request form will be completed and sent to Special Facilities personnel located in Von Neumann Hall.
  • Immediate maintenance needs can be obtained by contacting either Micheal Valenti at 258-3870 or  Eric Litostansky, Maintenance Supervisor, at 258-4565.
  • All emergencies involving facilities should be reported to Public Safety at 258-3134. The proctors will page the appropriate maintenance personnel, as necessary.
  • If maintenance is required in the laboratory, it is critical that there be good communications between laboratory personnel and maintenance workers in order to prevent accidents or accidental exposures to chemicals. For guidance in this area, see Section 13 of the Princeton University Health and Safety Guide, University Support Staff Activities in Laboratories.

    For More Information

    Additional chemical safety information is available in the Laboratory Safety Manual. The EHS web page has a plethora of safety information covering a number of topics including chemical safety, lasers, radioactive materials, electrical safety, and much more.

    Contact Information

    Mechanical and Aerospace Engineering Department