Lag Ba'omer bonfire fans should be careful not to cause monetary or environmental damage in their enthusiasm to celebrate, cautioned the two Israeli chief rabbis in an announcement on the Web site of the American Society for the Preservation of Wildlife in Israel. "When God created Adam he took him and showed him all the trees in Gan Eden," quoted rabbis Shlomo Amar and Yona Metzger from ancient homiletic literature (Kohelet Raba). "God said to him, 'Look at all my creations, how magnificent they are. All that I have created is for you. Be sure not to destroy my world, because if you do there is no one who can repair it." The chief rabbis urged the Jews of Israel to be careful with their bonfires to prevent unnecessary damage. They also called for the public to be scrupulous in protecting private property. On Thursday night, Jews across the world will celebrate Lag Ba'omer - the 33rd day of the Omer, which is counted between Pessah and Shavuot. The day is also the anniversary of the death of Torah sage Rabbi Shimon Bar-Yohai, who lived in the period immediately following the destruction of the Second Temple (70 CE). According to Jewish custom, large bonfires are lit in memory of Bar-Yohai, who, according to the Zohar, was bathed in intense light the day he died. The day also marks the halting of a plague that raged among the disciples of another Torah sage, Rabbi Akiva, who "did not act respectfully towards each other." However, preparations for Lag Ba'omer, such as the gathering of wood and other combustibles, often involve the stealing of private property by overly enthusiastic children. In addition, the large amount of smoke emitted by the fires is detrimental to the environment. In addition, just before and during Lag Ba'omer, Magen David Adom receives double the regular number of calls from children and teenagers who have been accidentally burned or hurt preparing bonfires. The festive day is usually celebrated with outings, bonfires, weddings and visits to Bar-Yohai's burial site in Meron (near Safed). MDA will be out in force at the tomb in Meron to provide any needed first aid for the more than 100,000 people expected to be there. MDA said that wooden planks or branches should be added to the fire carefully and gradually - when the wind blows from behind and not toward the bonfire. Bonfires should not be lit near trees or shrubs that could catch fire, and rocks should be placed around the bonfire. Small children must be under constant adult supervision and kept a safe distance away from the fire. In addition, MDA said, never use inflammable liquids to make the flames stronger - just additional wood. Also, keep a large container of water nearby to put out the fire, and mix the ashes with a stick to ensure that the fire is extinguished. If someone's clothes are set afire, lay the person on the ground and roll him in earth or sand, or extinguish the fire with a lot of water; alternately, one can cover the victim with a wet blanket or towel when his head is exposed. Call the fire service at 102 if the fire spreads, and MDA at 101 if someone is injured. Never remove burnt clothing that has stuck to the skin. Cool it with water if the damage is limited to a small area. Put clean (preferably sterile) wet bandages on the burn. Do not puncture boils, and never put creams or ointments on the burn. If a spark enters the eye, wash it well with a lot of cold water. Wearing closed, high-topped shoes, long pants and long-sleeved shirts is also recommended to avoid being bitten by snakes, scorpions or other creatures attracted to the fire. Food being cooked in aluminum foil, such as potatoes and onions, should not be touched directly when they are burning hot. Beterem, the national center for child safety and health, has also warned never to throw aerosol cans into a bonfire, as they can explode.