Nicole Herling, the sister of gunman Robert Card, rests her hand on his Army helmet while testifying to the commission investigating the Lewiston shootings. She told the commission that the helmet failed to protect her brother from the concussive blasts he was exposed to while training cadets at West Point. Gregory Rec/Staff Photographer

The Defense Department is implementing a new policy to protect military personnel from blast exposures, taking the step after an analysis showed that the Army reservist who committed the mass shooting in Lewiston last fall had sustained a brain injury from exposure to repeated grenade blasts.

Robert Card, who killed 18 people in a shooting rampage in Lewiston last October, was found to have suffered brain damage from instructing grenade training during his years in the Army Reserve, according to a Boston University scientific analysis of his brain tissue after the tragedy.

Maine’s congressional delegation, citing the link to the state’s deadliest mass shooting, has pushed for better safeguards and urged the military to speed up implementation of blast-protection policies.

A top Defense Department official issued a memo Thursday to say the reforms were moving forward, including baseline brain screenings for military service personnel.

“Experiences by (Department of Defense) personnel in training and operational environments demonstrate possible adverse effects on brain health and cognitive performance (e.g., headache, decreased reaction time, attention difficulty, memory loss) resulting from acute (e.g., single or short-term) and chronic (e.g., repetitive or continuous) exposure to blast overpressure,” Deputy Defense Secretary Kathleen Hicks said in an Aug. 8 letter to all defense personnel.

Sen. Angus King, I-Maine, said he is “encouraged by the new policies being put in place by the Department of Defense to address brain injuries caused by blast overpressure.”

In July, King wrote a letter to Defense Secretary Lloyd Austin urging the military to immediately begin implementing safety measures to prevent brain injuries.

“The more we focus efforts on the effects of blasts, the more we learn about the direct link to brain injury and how we can prevent these injuries in the future,” King said in a statement.

Hicks wrote that a number of reforms would be implemented, including:

• All military members must undergo baseline brain screenings as part of the “entry process” into military service. Active-duty members who are considered high risk must be screened by the end of 2025, while all active-duty and reserve members should be screened “as soon as possible.” King said with the baseline screenings, “we can learn how to manage these exposures with the aim of protecting their wellbeing and saving lives.”

• Providing protective equipment for personnel involved in weapons training where blast overpressure is a risk.

• Maximizing the distance from weapons that produce blast overpressure, especially those that exceed 4 psi (pounds per square inch).

• Warning military members of risks involved with training with weapons that exceed 4 psi, and how to minimize the risks.

• Establishing protocols so that military personnel “recognize blast overpressure symptoms, report exposures to their command, and seek an evaluation from their medical provider if experiencing symptoms.”

All four members of Maine’s congressional delegation – King, Republican Sen. Susan Collins, and Democratic Reps. Chellie Pingree and Jared Golden – are supporting a bill called the Blast Overpressure Safety Act, which would reform training protocols to reduce brain injuries.

The bill is included in the Senate version of the National Defense Authorization Act that has yet to move forward in the House. It would mandate the baseline screening, retool training protocols to prioritize brain safety and change the design of weapons during their manufacture to lessen their impact during training.

Card, the Lewiston shooter, had been experiencing deteriorating mental health in the months before the tragedy, including psychotic episodes and hearing voices, according to people who knew him. Police were alerted about his increasingly erratic behavior, and Card spent two weeks last summer at a New York psychiatric facility at the urging of his Army Reserve commanding officers.

During his years of grenade training in New York state, Card was “exposed to thousands of low-level blasts,” according to the Boston University brain tissue analysis. Card died of a self-inflicted gunshot wound.

King said the policy “marks another positive step toward helping our community heal, while also working to prevent unnecessary harm moving forward to our service members and veterans.”