 There are thousands of stories in the oil patch, tales of adventure and excitement, of looking for oil, finding it, producing it. Usually, the endings are happy. Sometimes they aren't. Many stories end sadly with everything was going fine until my patients did a lot of things safely. It only took one mistake. John knew driving to and from the rig can be dangerous. The hazards include weather, road conditions, and himself. If he's tired, he asks for relief, normally not working over 16 hours in a 24-hour period. When road or weather conditions make passage too difficult, he cancels the inspection. When he's driving and he gets too tired, he pulls over and rests. On this trip, John took bottled water and a flashlight to a workover rig in a remote area. He knew that workover rigs are usually older than drilling rigs, thus potentially more dangerous. Arriving at the well site, he watched for guy wires and low, hard-to-see objects. On site, he wore a hard hat and prescription lenses purchased by the division. His shoes had heels and steel toes, which are preferable but not required. But John's clothing was loose. His sleeve caught on a handle. He fell, and now he's in my office. Fred knew that the rig area is the most dangerous well site location. The rig floor is especially slippery, often coated with mud and sometimes with oil. He knew that rig cleanliness can reflect the quality of well operations. He tested the handrails before relying on them and used the stairs and handrails on his way up and down from the rig floor. On the rig, he stayed close to the driller's station. He kept a safe distance from the draw works and power transmissions. The rotary table, the tongs when in use. And the drill pipe, drill collars, and testing tools as they're made up. Run into the hole, pulled from the hole, and broken down. He stayed away from detonating devices, such as perforating tools. These can go off unexpectedly, especially when they fail to discharge in the well bore and are pulled from the hole. Once detonating devices are pulled from the well, he would leave the rig floor. In any event, he stayed on the rig no longer than it was necessary. He watched for falling objects, and he didn't stand on or beneath casing or drill pipe. When the kelly was moved to or from the rat hole, Fred wasn't under the rotary hose. He was careful near drilling mud, which can be caustic and hot. But he walked on a soft bank around the earth and mud pit. Undercut and unable to support him, the bank collapsed. Fred fell into the pit. Mike knew a drill site is crossed with lines, cables, and chains. All can be dangerous. He tried to walk where he wouldn't be hit if they broke. Mike didn't straddle them and was careful not to trip. He knew that a baler is fastened to a sand line. When the line is slack, loops can develop. He didn't stand near the sand line, which can tighten any time. The cat head attached to the draw works is usually spinning. As he walked on the rig floor, Mike was careful of the cat head, of the cat lines, and of items suspended from them. He knew the tongs are fastened to a cable, usually slack. The cable snaps tight as the drill pipe is made up, but he didn't pay attention. The cable struck him, breaking his leg. Jane knew a well site has two main high pressure systems, one for mud and fluid circulation and one for blowout prevention. Lines into and out of these systems are under high pressures and extremely dangerous when broken. She knew not to stand any closer than necessary. Jane was aware of avenues of escape in case of rupture. She was especially careful during a pressure test as lines are pressured up or bled off. When someone hammered on pressurized pipe, she moved away. She never looked for fluid leaks down the well board during a B.O.P.E. test or at any other time. Mud can blow out of the hole and cause serious injuries. She checked the pressure gauges for pressure losses instead. On a B.O.P.E. test, she made sure enough pipe was in the hole to wait the drill string while the well was pressured up. Without sufficient weight, the drill pipe could be blown out of the preventers. She knew that if she had doubts, she should leave the rig floor before the well was pressured up. But after the test, before the preventer was open, she forgot to check the choke manifold pressure gauge. Some pressure remained in the well. Mud blew from the hole, injuring Jane. Joe knew that well sites can be dangerous during changeover operations when a lot of dissolved gases in the crude oil or free gases in the well board. He stood no nearer to the rig than necessary. He watched for sources of open flames, such as exhaust pipes without spark arrestors and cigarette lighters. He knew that the well board should be full of mud before a cavity shot can be made. A cavity shot may ignite gas that is built up in a well if the gas has not been displaced. He avoided a high pressure line from the cement truck, but stood too close to the mud lines. One burst, and he was struck by a whipping hose. Sally knew that hydrogen sulfide is a colorless gas as toxic as hydrogen cyanide. Smell does not always indicate gas presence or concentration. She read the division H2S manual and avoided areas with posted warnings when possible. At well sites in known H2S areas, she stayed upwind from emissions and followed the operator's H2S program. She wore a division indicator badge and brought along her H2S kit containing a small mask and a few minutes of air. She let qualified well site personnel check for H2S concentrations when her detection equipment was inadequate. She didn't look into tanks or other oil field containers, especially those with lids. She knew that H2S danger can be high when steam is bled off from oil wells. Because H2S is heavier than air, she was cautious in low areas throughout the field, avoiding them when possible. Low areas at well sites are especially dangerous, but Sally forgot. She bent too close to a well seller and was overcome by H2S fumes. Clearly, your best protection during well site operations is awareness of potential dangers and knowledge of how to avoid them. So be aware, be safe, and don't make that one mistake.