The local water district is replacing the mains in my city. In order to support all of the heavy equipment they are using, several of the contractors have parked large tanks of diesel fuel at strategic locations. Typically, they are simply left in a legal parking spot somewhere on a residential street. All of these thanks are labeled with large warning signs: “CAUTION – contains diesel fuel. No smoking within 50 feet!” Is this legaly enforcable? If one of these tanks were to be parked in front of my house, for example, my front porch, where I usually smaoke, would be well within a 50 foot radius. Could I no longer smoke on my own property?