With the contract between UPS and the Teamsters Union set to expire in July, Teamster General President Sean O’Brien said the union’s members “have never been more prepared for a strike.”

Heat protection, wage and organization improvements, and driver surveillance are all driving factors that might lead to a walkout. With UPS and Teamsters both promising to hold firm in contract negotiations, the first UPS workers’ strike in 25 years could be imminent.

UPS has nearly half a million total employees and 360,000 delivery and warehouse workers. In 2019, a contract was agreed upon by UPS and the Teamsters which made UPS delivery drivers some of the best-paid in the industry, but also added several provisions that have raised alarms over the years.

To compete with other shipping giants, the contract allowed the inclusion of a new set of drivers who would work Tuesday through Saturday, ensuring that customers got Saturday deliveries. Yet this class of drivers could only earn up to $30.64 per hour, while regular service drivers could earn up to $40 per hour.

“That is definitely a strike issue,” O’Brien said after a wave of complaints from drivers.

Recognizing that UPS needs to maintain a seven-day delivery schedule in order to stay competitive, O’Brien said, “We’re open to finding a solution to the seven-day week delivery because [of] what the competition is doing,” but explained that the current situation was untenable.

O’Brien is also calling for shorter hours in the summer months after the death of a 24-year-old UPS driver from heat stroke. The vast majority of UPS vans do not have any air conditioning. However, shorter hours would require more staff to be hired.

Other issues on the table include raising the entry-level wage and eliminating sensors and cameras that monitor UPS drivers.

“Inward-facing sensors act like motion detectors, similar to home motion security systems, alerting our drivers to at-risk driving behaviors such as not fastening their seatbelt and repeatedly using a cell phone while driving,” a UPS spokesperson said of the devices. “The data may be used to provide in-person coaching and training.”

O’Brien called the cameras an “invasion of privacy.”

With contentious issues teed up for the spring negotiations, the Teamsters have created a $350 million fund in case of a strike. The group has also shortened the time it takes for members to receive a payout, down from eight days to just one.

UPS CEO Carol Tomé will head the negotiations on the side of UPS, with the upcoming talks being her first.

“We have built UPS into the world’s leading package delivery company together, which has also bolstered Teamsters membership over the years. We believe we’ll continue to find common ground with the Teamsters and reach an agreement that’s good for everyone involved,” a UPS spokesperson told Insider in July.