A mail carrier who worked for the U.S. Postal Service for 28 years died on the job Friday, as a massive heat wave hit Los Angeles. 
 
 Peggy Frank, 63, was sitting in her mail truck in the Woodland Hills area when she was found unresponsive by a neighbor, a spokesperson for the Los Angeles County Department of the Medical Examiner-Coroner’s office told PEOPLE. Paramedics arrived on the scene and tried to revive Frank, but she was pronounced dead at 3:35 p.m. local time. 
 
 Temperatures in the area that afternoon had reached 117 degrees, CBS Los Angeles reported. An excessive heat warning for the region had even been released by the National Weather Service. 
 
 USPS trucks are not equipped with air conditioning, CBS Los Angeles reported. It’s unclear whether the heat lead to her death. 
 
 The corner’s office told PEOPLE that an official autopsy had been completed but that her cause of death was “deferred pending additional tests.” Results from those can take between four a six weeks. 
 
 “Our thoughts and prayers are with the employee’s family at this difficult time,” a representative for the USPS told PEOPLE in a statement. “The unfortunate incident involving this employee remains under investigation. This includes the underlying cause(s) of the employee’s death.” 
 
 The spokesperson added that postal carriers are encouraged to prioritize safety as they often work through all kinds of extreme weather. 
 
 “The safety of our employees is a top priority and the Postal Service has implemented a national Heat Illness Prevention Program (HIPP) for all employees,” the statement said. “In connection with the HIPP, the Postal Service provides mandatory heat-related and other safety training and instruction to all employees and assures they have the resources needed to do their jobs safely. Carriers are reminded to ensure they’re hydrated, wear appropriate clothing, including hats, get in the shade whenever possible, and to take sufficient amounts of water and ice with them out on their routes.” 
 
 Friday was Frank’s first time back at the Woodland Hills Post Office in months after suffering a broken ankle, her family told KTLA. She resided in North Hills and was just months away from retiring. Frank was also a mother of two and grandmother. 
 
 “I can not believe it because I don’t think that it should have happened,” her sister Lynn Calkins explained to KTLA, adding that Frank had suffered a heat stroke last year during the hot summer months. 
 
 “I’m so sad because she was going to retire soon. Now she can’t,” Calkins added to the outlet. “[The U.S. Postal Service] need to start caring about their people a little bit more. They need to change things a little so it happens to nobody else.” 
 
 Frank’s son, Kirk Kessler, blamed the USPS too. 
 
 “To have my mom 107 [degrees], humidity, carrying the mailbag around with no air conditioning in the car — yeah, I’m sure she’s probably gonna overheat,” he told CBS Los Angeles. 
 
 Coworker Joni Hogan Salvatore — who remembered Frank as an “amazing” coworker, a “very hard worker” and “just a really good person” – told The Los Angeles Daily News that the mail trucks are 10 to15 degrees hotter inside. 
 
 “They make us lock them and seal them for safety of the mail, but it’s horrible in there,” she said. ||||| A longtime U.S. postal carrier was found dead in her mail truck in Woodland Hills on Friday afternoon amid blistering summer temperatures, authorities confirmed Monday. 
 
 Peggy Frank, 63, of North Hills was found unresponsive while seated in a postal vehicle in the 4800 block of Calderon Road by a co-worker or bystander, said Ed Winter of the Los Angeles County Department of Medical Examiner-Coroner’s office. 
 
 Paramedics attempted to revive her without success, Winter said. Frank was pronounced dead at 3:35 p.m. Friday. 
 
 UPDATE: Federal investigators launch probe into Woodland Hills mail carrier’s death on 117-degree day 
 
 Temperatures soared to 117 degrees in the Woodland Hills area on Friday, surpassing the record of 106 degrees for that day, July 6, that was set in 1976. (The National Weather Service has kept records there since 1949, according to Keily Delerme, a NWS meteorologist.) 
 
 But Winter could not say Monday whether the heat was a factor in Frank’s death. 
 
 While her autopsy had been completed, the cause of death was deferred pending additional tests, Winter said. She also had some type of medical history that Winter declined to specify until the final cause of death is determined. 
 
 “We want to express our thoughts and prayers for the employee’s family at this difficult time,” said Evelina Ramirez, a spokesperson with the U.S. Postal Service. 
 
 She noted that carriers deliver mail in “all kinds of weather, including high temperatures.” 
 
 “Safety is our top priority for all of our employees,” Ramirez said. “The Postal Service strives to ensure that they have the tools and training to do so safely.” 
 
 Carriers are reminded daily to stay hydrated, wear appropriate clothing, such as hats, and get into the shade whenever and as much as possible, she said. 
 
 “The most important thing is to make sure they have water and ice for their entire route,” Ramirez said. 
 
 Employees at the Woodland Hills Post Office remembered Frank, a dog lover who had some 28 years working at the post office, as always upbeat and positive despite her health challenges. 
 
 “She was a sweetheart – always happy, even when she wasn’t feeling good,” said co-worker Cindy Pritchard. 
 
 Frank had recently returned from medical leave, according to colleagues. 
 
 Co-worker Joni Hogan Salvatore, who started working at the Woodland Hills Post Office before Frank, called her colleague “amazing” and “a very hard worker.” 
 
 “None of us are 20 (years old) anymore; it’s a hard job,” Salvatore said. “It’s a super-hard job, but she always had something nice to say. Never was a complainer or anything. She was just a really good person.” 
 
 Salvatore said that when it’s 100 degrees outside, it can be 10-15 degrees hotter inside the mail trucks, which do not have air conditioning. 
 
 “They make us lock them and seal them for safety of the mail, but it’s horrible in there,” she said. 
 
 The National Weather Service had issued an excessive heat warning on Friday for the region. 
 
 A spokesman for the U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA), which has jurisdiction over federal employees, could not be reached late Monday for comment. 
 
 In the fall of 2014, an administrative law judge upheld a willful citation to a U.S. Postal Service station in Independence, Mo., by the federal OSHA after a mail carrier died in July 2012, according to media reports. 
 
 The mail carrier had collapsed while working his route and died as a result of his exposure to excessive heat, according to an OSHA investigation. 
 
 That investigation found that the Postal Service “did not have procedures in place to address worker concerns during times of excessive heat,” according to the administrative agency. A willful violation is one that is committed with intentional, knowing or voluntary disregard for the law’s requirements or with plain indifference to worker or safety health. 
 
 The Postal Service was required to pay a penalty of $70,000 in that case, according to the news site Fox4KC.com. 
 
 In October of 2016, OSHA cited the Postal Service after two Des Moines, Iowa, workers suffered heat-related illness while delivering mail that past summer. The agency found that the two mail carriers, one of whom was told to continue walking her route despite feeling ill, were exposed to excessive heat. 
 
 RELATED STORY: Employees should ‘force breaks’ in extreme heat, top LA County health official says ||||| Please enable Javascript to watch this video 
 
 A 63-year-old postal worker was found dead in her mail truck in Woodland Hills as temperatures pushed toward 120 degrees last Friday, her family members said. 
 
 Peggy Frank of North Hills had worked for the U.S. Postal Service for 28 years and was nearing retirement. She had just returned to work for the first time in months on Friday after suffering a broken ankle, according to loved ones. 
 
 Frank was pronounced dead at the scene on the 4800 block of Calderon Road after paramedics attempted to revive her, the Los Angeles Daily News reported. The temperature in the neighborhood had reached 115 degrees that day, according to the National Weather Service. 
 
 L.A. County coroner's officials said although an autopsy has been performed, Frank's official cause of death is still pending. But — especially because the carrier vehicles have no air conditioning — her family believes it's possible her death was related to Friday's extreme heat. 
 
 “I can not believe it because I don't think that it should have happened,” said Frank's sister Lynn Calkins. “I’m so sad because she was going to retire soon. Now she can’t.” 
 
 Frank had suffered heat stroke last year during the scorching summer months, Calkins added. 
 
 Some of Frank's distraught relatives flew to L.A. from Arizona, still in shock that the vibrant mail carrier — who many neighbors in this Woodland Hills community considered a family member — died so unexpectedly. Calkins places part of the blame on the Postal Service 
 
 “They need to start caring about their people a little bit more,” she said. 
 
 A Postal Service representative said in a statement that it's "been a very challenging time. Our thoughts and prayers are with the employee’s family at this time.” 
 
 The spokesperson added that while mail trucks aren’t equipped with air conditioning units, “the safety of employees is always a priority.” Workers are reminded every day to stay hydrated, wear appropriate clothing and hats, carry sufficient amounts of water and ice and to stay in the shade as much as possible. 
 
 But for Calkins, that's not enough. “They need to change things a little so it happens to nobody else,” she said. ||||| NORTH HILLS (CBSLA) — A family is in mourning after a mother and grandmother who worked as a mail carrier died during the heat wave that hit Southern California over the weekend. 
 
 The Los Angeles County Coroner said Peggy Frank, 63, was found unresponsive in her mail truck Friday afternoon in the Woodland Hills area, where temperatures reached 117 degrees. 
 
 “To have my mom 107 [degrees], humidity, carrying the mailbag around with no air conditioning in the car — yeah, I’m sure she’s probably gonna overheat,” Frank’s son Kirk Kessler told CBS2 News. 
 
 After multiple attempts by paramedics to revive her, Frank was pronounced dead. She had been with the U.S. Postal Service for 30 years and was just a few years away from retirement. 
 
 Residents in the area saw the activity of emergency crews but had no idea what was happening. 
 
 “She was very nice,” said one man who was driving by the area Monday afternoon. “Now her face is coming […] in front of me, honestly, because I talked to her, and it becomes personal.” 
 
 Frank is survived by her two children and several grandchildren. 
 
 “She’s great, friendly, sensitive, always there for ya,” said Kessler. 
 
 The coroner said it’s not yet clear if the heat was the cause of her death. She had recently returned to work after having been off the job for more than two months with a broken ankle. 
 
 USPS would not go into details about Frank’s death but said their thoughts and prayers were with the family. 
 
 In Hemet over the weekend, an elderly couple was found dead inside their RV. Their air conditioner was not on when they were found.
– A 63-year-old postal carrier was found dead in her mail truck Friday amid a record-breaking heat wave in the Los Angeles area, CBS LA reports. Peggy Frank was found unresponsive in the Woodland Hills area, where temperatures had reached 117 degrees that afternoon, by a neighbor. Paramedics called to the scene could not revive her. Frank, who had worked for the US Postal Service for 28 years, was close to retirement. Friday was her first day back on the job after months off due to a broken ankle, KTLA reports. An autopsy has been completed, but her cause of death has been "deferred pending additional tests" and may not be determined for weeks, the coroner's office tells People. Frank's family believes the heat may have played a role in her death, and a colleague tells the Los Angeles Daily News that in such high temperatures, it can be as much as 15 degrees hotter inside the mail trucks, which do not have air conditioning. "They make us lock them and seal them for safety of the mail, but it’s horrible in there," she says. But a USPS rep, while expressing sympathy for Frank's family, says that mail is delivered in "all kinds of weather, including high temperatures" and that "the Postal Service strives to ensure that [carriers] have the tools and training to do so safely," including by reminding them to keep hydrated, have water and ice available for their entire route, stay in the shade when possible, and wear appropriate clothing.