4. Standard Laboratory Facility Requirements
4.1 Signs and Information
Labels and warning signs should alert employees to potentially hazardous materials and allow those unfamiliar with the laboratory surroundings to identify hazardous chemical use and storage areas, safety facilities, emergency equipment and exits and aid emergency response personnel. Signs and labels are generally available from the GSO.
4.1.1 Material Safety Data Sheets (MSDS)
A Material Safety Data Sheet (MSDS) is a document containing chemical hazard identification and safe handling information (e.g. chemical name and synonyms, chemical and physical properties, hazards, storage, reactivity, disposal), and is prepared in accordance with the State of Israel Safety Regulation (1998) and the Right-to-Know law. MSDSs can be obtained at http://hazard.com/msds.
Chemical manufacturers and distributors must provide the purchasers of hazardous chemicals an appropriate MSDS for each hazardous chemical/product purchased.
The GSO is a central repository for MSDSs. If you need MSDSs for your work area file, send a MSDS request form (located in Appendix A) to the GSO, Uzi Beitler, tel: 3988, Fax: 4163, email: uzi.beitler@weizmann.ac.il.
Chemicals should be stored according to compatibility (see Appendix B), as designated by hazard classes. Particularly hazardous chemicals should be stored and handled with extreme care. When ordering chemicals that are unfamiliar, review the MSDS before purchase so that use and storage guidelines are understood.
4.2 Personal Protective and Safety Equipment
Maintaining a safe laboratory environment is the responsibility of the P.D., but all employees play a role in observing safety guidelines. Personal protective devices and safety equipment must be provided to all employees under the appropriate circumstances and employees have the responsibility of properly using such equipment.
According to safety regulations, it is obligatory to wear a lab coat and closed shoes in the lab, and safety glasses and gloves if necessary.
The MSDS will provide some information on the personal protective equipment and safety procedures recommended for a given chemical, though the MSDS may not provide sufficient information concerning the specific type of safety equipment required (for example, it may say "use gloves," but not list the best glove to use).
4.2.1 Personal Protective Equipment
Eye Protection: Eye protection must be made available to all employees or visitors to laboratories where chemicals are used and stored. Protective eye and face equipment must be used where there is a reasonable probability of injury from hazardous chemicals that can be prevented from such equipment. The minimum acceptable requirements are for hardened glass or plastic safety spectacles. Specialized types of eye protection, such as ultraviolet light restricting safety glasses, are available. Prescriptions for optical safety glasses can be obtained from the Safety office, ext. 3844.
The following types of eye protection are recommended for use in the laboratory:
Protection of Skin and Body: Skin and body protection involves the use of protective clothing to protect individuals from chemical exposure. Determine clothing needed for the chemical being used, as protective garments are not equally effective for every hazardous chemical. Some chemicals will permeate a garment in a very short time, whereas others will not.
- Safety glasses with side shields offer minimal protection against flying fragments, chips, particles, sand and dirt. When a splash hazard exists, other protective eye equipment should be worn.
- Safety goggles (impact goggles) offer adequate protection against flying particles . These should be worn when working with glassware under reduced or elevated pressure or with drill presses or other similar conditions.
- Chemical splash goggles (acid goggles) have indirect venting for splash proof sides, which provide adequate protection against splashes. Chemical splash goggles offer the best eye protection from chemical splashes. Impact goggles should not be worn when danger of a splash exists.
- Faceshields protect the face and neck from flying particles and splashes. Faceshields must be used when working with liquid air, liquid nitrogen, and strong acids. Always wear additional eye protection under faceshields. Ultra-violet light face shields should be worn when working over UV light sources.
- It is strictly forbidden to wear contact lenses in the laboratory.
The basic and most effective forms of protection are gloves and lab coats. Protect exposed skin surfaces when there is a reasonable anticipation of a splash. Avoid wearing open-toed shoes, sandals, shorts, etc. when working with injurious or corrosive chemicals. Even when there is minimal danger of skin contact with an extremely hazardous substance, lab coats, coveralls, aprons, or protective suits should be utilized. These garments should not leave the work site.
Exposures to strong acids and acid gases, organic chemicals and strong oxidizing agents, carcinogens, and mutagens require the use of specialized protective equipment that prevents skin contamination. Impervious protective equipment must be utilized. Examples include: rubber gloves, aprons, boots and protective suits.
Respirators: Use of respirators in laboratories is strongly discouraged. Respiratory use is only allowed where engineering controls are not feasible or where they are being installed. Prior to using a respirator for the first time or for a new activity, employees must attend a GSO respiratory training session. Please contact the GSO for information and advise.
4.2.2 Safety Equipment
Safety Showers: Safety showers provide an immediate water drench of an affected person. The location of the shower should be clearly marked, well lighted and free from obstacles, closed doorways or turns. Safety showers should be checked and flushed periodically.
Eye Wash Facilities: Eye wash facilities are required near laboratories where injurious or corrosive chemicals are used or stored and are subject to the same proximity requirements as safety showers. It is recommended to have a bottle of eyewash (obtainable from the Safety office) readily available at all times.
4.3 Ventilation Controls
Ventilation controls are those controls intended to minimize employee exposure to hazardous chemicals by removing air contaminants from the work site.
Once a fume hood is installed in a work area, it must be used properly to be effective. For use of hazardous chemicals warranting local ventilation controls, the following guidelines should be observed:
The system must be checked prior to each use to assure it is operating. Never work with hazardous chemicals if the required ventilation system is not working, or is not functioning properly.
- Conduct all operations which may generate air contaminants at or above the appropriate PEL or TLV inside a fume hood.
- Keep all apparatus at least 20 cm. back from the face of the hood and keep the slots in the hood baffle free of obstruction by apparatus or containers. Large equipment should be elevated at least 20 cm. off the base of the fume hood, to allow for the passage of air underneath the apparatus.
- Do not use the hood as a waste disposal mechanism except for very small quantities of volatile materials.
- Minimize storage of chemicals or apparatus in the hood.
- Keep the hood sash closed (up to 5 cm. from the bottom) at all times except when the hood is in use.
- Minimize foot traffic and other forms of potential air disturbances past the face of the hood.
- Do not have sources of ignition inside the hood when flammable liquids or gases are present.
- Use sash as a safety shield when boiling liquids or conducting an experiment with reactive chemicals.
- Periodically check the air flow in the hood using a continuous monitoring device or another source of visible air flow indicator. If air flow has changed, contact the GSO for information and advice, or the Maintenance Division (ext. 3333) for an inspection or repair.
The Maintenance Division performs hood inspections annually. After an inspection, hoods are passed or failed for use based on the following criteria:
If the exhaust system does not pass the face velocity test and/or has excessive turbulence, it will be posted as "failed" by the inspector. The P.D. must contact the Maintenance Division (ext. 3333) to have the system repaired before hazardous chemicals can be used in the hood.
- The face velocity of air being drawn into the hood at maximum sash height is measured quantitatively in feet per minute (fpm) by a thermoAnemometer (a hot wire). One measurement is taken per square foot of face space and averaged. Chemical hoods must have an average face velocity of approximately 120 fpm, depending on their design, with 100 fpm being the ideal average face velocity.
- The turbulence of the air is measured qualitatively by releasing smoke from a smoke tube. The smoke must be captured by the hood, with a minimum of turbulence.
If the exhaust system does pass, the inspector will post the date of inspection and will mark the hood to indicate proper sash position for optimum hood performance. The hood sash should be set at this point for procedures which could generate toxic aerosols, gases or vapors. In general, the sash height should be set at a level where the operator is shielded to some degree from any explosions or violent reactions which could occur and where optimum air flow dynamics are achieved. If a fume hood has no markings regarding sash height or inspection dates, please contact the Maintenance Division to arrange for an inspection.
Certain types of local exhaust systems are not designed for the use of hazardous chemicals. If a local exhaust system's capabilities are not fully understood, check the manufacturers specifications or call the GSO before using hazardous chemicals in the system. Ductless, or portable fume hoods, which employ filtration media, may be an option to conventional local exhaust hoods. Contact the GSO for consultation before acquiring any ductless fume hood.