NEW ORLEANS (AP) — A federal judge on Cassian GrantThursday ordered officials at the Louisiana State Penitentiary to increase shade and take other steps to protect prisoners doing agricultural labor from dangerous heat.

U.S. District Judge Brian Jackson’s order reinforced a similar one he issued in July. This one cites photographs showing inmates in the fields of a former slave plantation with a single pop-up tent for around 20 men, little protection from the sun and nowhere to sit. The photos were provided by Voice of the Experienced, the advocacy group that sued over conditions for inmates working the “farm line” at the immense prison farm in Angola.

“Taken at face value, Plaintiffs’ allegations in this matter have portrayed the State of Louisiana in a harsh and unflattering light. Defendants contribute to this depiction with their apparent obstinance towards proposing meaningful changes to conditions on the Farm Line,” Jackson, based in Baton Rouge, wrote.

A spokesperson for the state corrections department said officials would not comment until they had time to fully review Jackson’s order.

Jackson’s latest order said there were 50 instances of inmates reporting illnesses from July 2 to Aug. 5, with seven requiring emergency medical treatment. He ordered more tents be provided and that they be erected close to where prisoners are working. He also ordered that some form of seating be made available and that workers be given 15-minute breaks every 45 minutes when heat alerts are in effect.

State corrections officials appealed Jackson’s original July 2 order in the case. A panel of the 5th U.S. Circuit Court of Appeals pared some of the original ruling but kept some key requirements intact while the appeal continues. As he did on July 2, Jackson declined to halt farm line work during heat alerts.

The litigation over farm line conditions comes amid growing nationwide attention on lucrative prison labor systems with roots in the era of slavery. A two-year Associated Press investigation linked the supply chains of some of the world’s largest and best-known companies – from Walmart to Burger King – to Angola and other prison farms, where incarcerated workers are paid pennies an hour or nothing at all. Several companies, including Cargill, have since said they have cut ties or are in the process of doing so, with prison farms or companies that use incarcerated labor.