Chemical Hygiene Plan

OSHA’s Occupational Exposure to Hazardous Chemicals in Laboratories standard (29 CFR 1910.1450) describes the requirements for a chemical hygiene plan. There are eight requirements for a chemical hygiene plan. There must be written standard operating procedures that are relevant to safety and health considerations for each activity involving the use of hazardous chemicals. The second requirement listed the criteria that the employer must implement measures to reduce exposures to hazardous materials. The exposures are prevented with either engineering controls, the use of personal protective equipment or PPE, and administrative controls. The third requirement states that fume hoods and personal protective equipment must be functioning properly and ensure the proper maintenance of the equipment. The fourth requirement is that there needs to be the proper information to be available to the lab personnel: the contents of the laboratory standard, the location of the chemical hygiene plan, the permissible exposure limits for OSHA regulated substances or recommend exposure limits for other hazardous chemicals where no standard exists, the signs and symptoms associated with exposures to hazardous chemicals used in the laboratory, and the location of the Material Safety Data Sheets. The fifth requirement describes the circumstances under which a particular laboratory procedure requires prior approval from the employer before being implemented. The sixth requirement states that there needs to be a person appointed for the position of the Chemical Hygiene Officer and a Chemical Hygiene Committee.  The seventh requirement is for provisions for additional worker protection for those that work with hazardous substances. These hazardous substances are under the title of “select carcinogens,” reproductive toxins and substances that have a high degree of acute toxicity. Employees must use a fume hood or glove boxes when using these kinds of chemicals. There must be strict directions for the safe removal of contaminated waste. The eighth and final requirement is that the employer must evaluate the effectiveness of the chemical hygiene plan.

Employees must have the correct training, this includes: the physical and health hazards of the chemicals that are used in the work area, methods that are used to detect the presence of hazardous chemicals in the workspace, and training on the proper use of personal protective equipment and other ways to protect themselves from the hazards. If an accident were to happen the workers need the opportunity to have medical consultation to determine the need for further medical attention. An accident could be a spill, leak, explosion, or another occurrence.

Most colleges have their Chemical Hygiene Plan on their main screen of their laboratory page ever since the accident at UCLA. This has set a standard for all colleges and having students in the labs for them to be safe. These plans normally all cover the same areas and some can be as long as 1,500 pages. These plans are supposed to be reviewed every year however, this is not always done since they are so extensively detailed and long. In reality not much is to be changed from year to year when they are reviewed.

http://www.ors.od.nih.gov/sr/dohs/documents/nih%20chemical%20hygiene%20plan.pdf

http://www.ehs.wisc.edu/chemicalhygieneplan.htm

https://www.osha.gov/Publications/laboratory/OSHAfactsheet-laboratory-safety-chemical-hygiene-plan.pdf

Handling Cryogenic Gases Safely

Cryogenic materials are compounds that have to be cooled to an extremely low temperature to change from a gas to a liquid. It is important to keep them at this low temperature to make sure they remain in the gas phase. They are also known for their high expansion rate when the compound is in the gas phase. Some examples of cryogenics are: helium, argon, nitrogen, methane, and oxygen. Many cryogenic gases are flammable which could lead to fire and explosion hazards in the workplace. When in use you must keep any ignition sources away from the area where cryogenic gases are being used. Some examples include: open flames, welding, and electrical equipment when not intrinsically safe.

I found the equivalent of American OSHA, Occupational Safety and Health Administration, but in Canada it is called the Occupational Health and Safety or OSH. Their webpage had a ton of great information on how to work safely with cryogenic gases. Their best “solution” to how to work safely with cryogenic gases is to not work with them but to substitute them out for another product. They did admit that this may not always be possible with a specific job but they suggested communicating with your chemical supplier for a recommendation on a safer substance. Another safety measure is to have the proper personal protective equipment or PPE when handling cryogenic gases due to the extremely low temperatures they are kept at any contact with the skin could cause serious burn leading to frostbite. In the gas phase they can cause permanent damage to the eyes and other delicate tissue with just a moments exposure. Workers must not only protect their hands from burns but their full bodies as well. The correct workmen personal protective equipment should include: full-face shield, goggles, vinyl gloves specially designed to prevent cryogens from flowing into the gloves, lab coats and high-top closed toed shoes.

When working with cryogenic gases there needs to be proper ventilation to prevent asphyxiation of the workers, and the storage of the containers should not be kept in enclosed spaces. Proper ventilation also reduces the risk of fire or explosion in the workplace. The hoods, ducts, air cleaners, and fans must be made from materials compatible with cryogenic gases where they are being used or stored to avoid any problems.

Cryogenic liquefied gases are stored in heavily insulated containers because they are kept at or near boiling point to keep it in the liquid phase. However, since it is not perfect there is always some gas in the containers. This could become a potentially dangerous situation if too much gas begins to build up in the container due to the large expansion ratio from liquid to gas, creating a buildup of high pressure in the container. Avoidance of this issue is easy with the proper installment and appropriate use of a pressure relief device on the container. Since these devices are so important it is vital to check for leaks on a regular basis.

http://oehs.vcu.edu/chemical/labsafe/cryogenics_safety.pdf

https://www.ccohs.ca/oshanswers/prevention/cryogens.html

The Handout given in class: Physical Hazards Slides