After the school shooting in Parkland, Fla., school safety upgrades people can see and touch have gotten a lot of attention. Things like video surveillance, door-locking systems, and other physical improvements to schools are often the focus of parents and the general public when they share concerns about the security of their schools.

It’s important to remember that measures taken to prevent school violence before it happens, while they don’t get a ton of news coverage, can be the most important element of safety and crisis-prevention plans. But there’s something else to keep in mind: The physical upgrades to schools added in the name of safety often aren’t cheap.

Last October, the Partner Alliance for Safer Schools (PASS) released a series of cost estimates for schools that want to reach four different levels of security and safety. The Security Industry Association and the National Systems Contractors Association, both industry groups that prepared the estimates for PASS, listed a series of improvements schools could make to get from Tier 1—the basic level—to Tier 4, the top level of security for schools according to PASS.

Let’s start at the top. Here are a few of the measures PASS says a school needs in order to have “Tier 4" security:

• Bullet-resistant glass;
• Gated parking with card-based access;
• Mobile applications for video surveillance;
• Visitors who are pre-enrolled in a school’s system;
• Emergency notifications that are integrated with weather and fire alerts.

That assumes a school already has upgrades required to reach the first three tiers, including prerequisites to reach Tier 1 like perimeter signage, self-adhesive visitor badges, and security policies and procedures, up through setting up video surveillance in all common areas and equipping staff with two-way radios.

So when you add up all the prerequisites to become a Tier 4 school what’s the cost? It depends on the type of school, but here are the two specific estimates from PASS:

K-8: $312,241

High School: $539,388

The estimates for these and other costs were based on security upgrades made at Columbine High School in Littleton, Colo., the site of a 1999 school shooting. Both the Security Industry Association and the National Systems Contractors Association acknowledge that these costs might vary depending on local markets. (And again, keep in mind, these figures are coming from trade groups.)

The costs go down from there, although the money required for high schools doesn’t go down neatly in tandem with the cash needed for K-8 safety upgrades. Creating a K-8 school with a Tier 3 security level, for example, would cost $200,000, while a Tier 2 high school would check in at $244,000. To achieve Tier 1 security, the respective figures are $94,000 and $170,000.

The Tier 1 safety measures “should be the minimum standard for all school buildings, but more action is required,” said Mark Williams, a member of the PASS steering committee, in a statement last October that accompanied the release of the cost estimates.

The PASS analysis didn’t break out the costs by individual security measure. But in an example of school security upgrade costs geographically relevant to Parkland, in 2016, the Miami-Dade district announced in 2016 it would spend $10 million over five years to install cameras, begin visitor screening, and take “a look at security staffing” at all schools.

In 2015, the Safe and Sound Schools organization reported that the cost of installing a protective film to make windows bullet-resistant was between $15 and $25 per square foot. (Safe and Sound, which works to create safer schools and provides crisis and recovery training, is led by parents whose children were killed by a gunman at Sandy Hook Elementary in Newtown, Conn., in 2012.)

Why do different grade levels matter in this discussion? In endorsing the PASS cost estimates, Secure Schools Alliance Executive Director Robert Boyd said that while 94 percent of incidents of “mass violence” at elementary schools are caused by outside intruders, just one-third of such incidents are caused by intruders in middle and high schools.

Appropriate Measures

It’s important to remember that in addition to many security meaures simply being out of districts’ price range in many instances, not all of the PASS security measures listed here may work at many schools, depending on their layout and location.

The STOP School Violence Act under consideration in the Senate would authorize $100 million in grants that could be used to pay for physical security infrastructure at schools. (The STOP Act approved by the House last week doesn’t allow for this in the grants.) But it’s a competitive-grant program. That means schools that might be in the most need of grants to help with security upgrades may also lack the time and resources just to prepare a strong grant application for the money, assuming the STOP Act becomes law. The Act also requires districts to put up 25 percent in matching funds, although that requirement can be waived in the Senate bill.

School administrators will also have to balance the interest in and public demand for security improvements with the training and crisis-intervention programs that would also be eligible for STOP Act funding, said Sasha Pudelski, an assistant director at AASA, the School Superintendents Association.

“No superintendent just wants to focus on one or the other,” Pudelski said.

Read about different tiers of school safety from PASS below:

Photo: Students are evacuated by police from Marjory Stoneman Douglas High School in Parkland, Fla., on Feb. 14, after a shooter opened fire on the campus. (Mike Stocker/South Florida Sun-Sentinel via AP)