Elements of a comprehensive business security program are cash security, information security, sabotage security, transit security, and site security. Regarding safes, Chubb is the recognized industry leader in Australia. Recognizing that no safe is impregnable, Chubb aims to slow down a burglar's entry with surprises, alarms, and puzzles. The most common form of attack against safes is with oxyacetylene torches. Specially designed safes with reinforced material resist such assault. Safes should also withstand fire. Regarding airport security, Webster's international security division gave four airports its top danger rating in December 1986: Manila in the Philippines, Bogota in Colombia, Colombo in Sri Lanka, and the Charles de Gaulle terminal in Paris. As regards industrial espionage, most companies take few precautions to protect valuable company secrets. This involves making sure that valuable information does not end up in the trash, that electronic listening devices are detected, and that phones are not tapped. Executive protection while traveling involves a thorough assessment of the risks associated with various areas of the world, which entails a constant monitoring of political and terrorist activity. This includes monitoring the security of airports throughout the world.