PITTSBURGH — Federal authorities have decided against issuing citations in a natural gas well fire in southwestern Pennsylvania that killed one worker earlier this year.

The federal Occupational Safety and Health Administration said no exact cause was determined for the Feb. 11 fire at the Chevron well in Greene County's Dunkard Township. No citations for violation of federal safety standards will be issued.

Ian McKee, 27, a field service technician, was killed.

The state Department of Environmental Protection said in a report last week the fire “may have been caused by human error” when a lock screw was ejected, allowing high-pressure methane gas to escape.

The state report said sufficient oversight was not always provided and a contract worker with no oil field experience worked on the well contrary to company policy.

WASHINGTON — U.S. retail sales were essentially flat in July, providing evidence that consumers have yet to shed their doubts about the economy despite recent job gains.The Commerce Department said Wednesday seasonally adjusted retail sales were unchanged in July compared with the prior month. Total sales rose a statistically insignificant $161 million from $439.6 billion in June.Spending dipped at auto dealers and department stores last month. The losses were offset by gains at grocery stores, gasoline stations, restaurants, clothiers and building material stores.The figures suggest Americans are hesitant to spend, which could limit growth for the economy. Retail sales are closely watched because consumer spending accounts for 70 percent of economic activity.Retail sales have flat-lined even though employers have added more than 200,000 jobs a month for the past six months. Payrolls increased by 209,000 in July and 298,000 in June.

SAN FRANCISCO — Apple is banning the use of two potentially hazardous chemicals during the final assembly of iPhones and iPads as part of the company’s latest commitment to protect the factory workers who build its trendy devices.The decision announced Wednesday comes five months after the activist groups China Labor Watch and Green America launched a petition drive calling on Apple to abandon the use of benzene and n-hexane in the production of iPhones.A four-month investigation at 22 factories found no evidence that benzene and n-hexane endangered the roughly 500,000 people who work at the plants, according to Apple. No traces of the chemicals were detected at 18 of the factories and the amounts found at the other four factories fell within acceptable safety levels, the Cupertino, Calif., company said.Nevertheless, Apple decided to order its suppliers to stop using benzene and n-hexane during the final assembly of iPhones, iPads, iPods, Mac computers and various accessories. What’s more, Apple is requiring all its factories to test all substances to ensure that they don’t contain benzene or n-hexane, even if the chemicals aren’t listed in the ingredients.