TExES Science 7-12 (236)

Laboratory safety is a primary responsibility for science educators. Teachers must ensure that all activities are conducted safely, that students understand safety protocols, and that appropriate supervision is maintained at all times.

Safety training should occur before any laboratory work begins. Students must demonstrate understanding of safety rules before participating in experiments. Safety protocols should be reviewed regularly and reinforced throughout the school year.

Safety goggles must be worn whenever there is a risk of eye injury from chemicals, projectiles, or heat. Goggles should form a seal around the eyes and meet ANSI Z87.1 standards. Regular eyeglasses do not provide adequate protection.

Lab aprons or coats protect clothing and skin from chemical spills. Aprons should be worn during all activities involving chemicals, heat, or biological materials.

Gloves protect hands from chemicals, biological materials, and heat. Different glove materials provide protection against different hazards. Nitrile gloves are appropriate for most chemicals, while heat-resistant gloves are required when handling hot objects.

Material Safety Data Sheets (MSDS) or Safety Data Sheets (SDS) provide detailed information about chemical hazards, handling procedures, storage requirements, and emergency responses. Teachers must have access to SDS for all chemicals used in the laboratory and must understand how to interpret this information.

Chemical labels provide critical safety information including the chemical name, hazard warnings, and handling precautions. The Globally Harmonized System (GHS) uses standardized pictograms to indicate hazard types.

Proper chemical storage requires separating incompatible chemicals. Acids and bases must be stored separately. Flammable materials must be stored in approved flammable storage cabinets away from heat sources and oxidizers. Chemicals should be stored at appropriate temperatures and protected from light when necessary.

Biological materials may contain pathogens that pose health risks. Standard precautions should be followed when handling any biological material, including treating all specimens as potentially infectious.

Preserved specimens may contain formaldehyde or other hazardous preservatives. Adequate ventilation is required when working with preserved materials. Students should wear gloves and avoid direct skin contact.

Live organisms require appropriate care and housing. Teachers must consider ethical treatment of animals, allergies among students, and proper disposal of living materials after investigations.

Heat sources (Bunsen burners, hot plates, heating mantles) pose burn and fire hazards. Long hair must be tied back, and loose clothing must be secured. Students should know the location and use of fire extinguishers and fire blankets.

Electrical equipment must be inspected regularly for frayed cords or damaged plugs. Electrical equipment should be kept away from water sources. Ground fault circuit interrupters (GFCI) should be installed in areas where water and electricity may come into contact.

Glassware should be inspected for cracks before use. Cracked or chipped glassware must be discarded. Hot glassware should be placed on appropriate surfaces and allowed to cool before handling.

Emergency equipment must be readily accessible and in working condition. Equipment includes fire extinguishers, fire blankets, eyewash stations, safety showers, first aid kits, and spill kits.

Safety showers are used when chemicals contact large areas of the body or clothing. Contaminated clothing should be removed while showering. Showers should flush the affected area for at least 15 minutes.

Fire response follows the RACE protocol: Rescue anyone in immediate danger, Activate the alarm, Confine the fire by closing doors, and Evacuate the area. Small fires may be extinguished using appropriate fire extinguishers if safe to do so.

Spill response depends on the material spilled. Chemical spills should be contained using appropriate absorbent materials. The SDS provides specific cleanup instructions for each chemical.

Supervision must be maintained at all times during laboratory activities. Teachers should never leave students unattended in the laboratory. Student-to-teacher ratios should allow for adequate supervision of all activities.

Advance preparation includes testing all procedures before conducting them with students, ensuring all materials and safety equipment are available, and reviewing potential hazards with students.

Documentation of safety training, accidents, and near-misses should be maintained. Accident reports should be filed according to school and district policies.