- FIRM PROFILE
The movement to provide more sustainable school buildings continues to grow. At the same time, the Sept. 11, 2001, terrorist attacks and recent campus shootings are driving education institutions to construct safer campuses and more secure buildings. Although these movements appear to have little in common, they complement each other in several areas. The U.S. Green Building Council’s LEED program rates buildings for compliance with engineering design principles and development strategies to produce more energy-efficient and environmentally friendly buildings, including:
So, just how do these strategies mesh with the call for better building security?
Where the security risks of a facility warrant (i.e., high-risk animal or medical research
facilities), vehicles should be screened for explosives before they can pass beyond a predetermined safe distance from the building perimeter. This “standoff” distance is based on an amount of explosives in a credible threat to attack the facility. This theoretical threat is the design basis threat.
The standoff distance is the distance from the building that must be contained in order to limit the losses to an acceptable level in an explosion. To be effective, this standoff distance must stop the design-basis-threat vehicle before it can proceed through the perimeter.
The perimeter barriers can consist of anything that sufficiently obstructs a vehicle from proceeding through the standoff perimeter. Some compatible strategies suggested by the LEED-NC (v.2.1) Reference Guide to better manage stormwater:
LEED also provides points for limiting site disturbance or exceeding the local green (open) space requirements by 25 percent, or providing green (open) space equal to the development footprint. Providing the needed standoff distance around the perimeter of the site often is seen as a waste of space. However, this intermediate space can be green space, thereby helping to meet LEED certification requirements.
Another way to better manage stormwater is to install a green roof, which stores and uses the rain water that otherwise would contribute to the stormwater supply. Vegetation cools the surrounding area by way of evapotranspiration. It also helps reduce the heat-island effect that is detrimental to humans and wildlife.
A green roof requires multiple layers of material: primer, rubberized asphalt, root block, insulation, filter fabric, growing media and plant material. These layers increase the time, effort and force needed to penetrate the roof.
LEED strategies aim to reduce energy costs, eliminate light trespass and minimize sky-glow. Effective safety lighting includes adequate and uniform levels of lighting along roads, driveways, parking areas and other places where pedestrian traffic is anticipated. Although it is possible to deal with very low lighting levels by using low-light-capable cameras or infrared light sources, people have a difficult time discerning people or objects in very low light levels, especially where very dark areas are flanked by a glaring light source or where distant people are backlighted.
LEED strategies can be employed to achieve credit for reducing light pollution. Designs can eliminate light trespass from a building and site, and minimize sky-glow to improve nighttime visibility. Concurrently, adequate light quality makes security cameras more effective and provides a sense of safety and security.
Effective exterior lighting design incorporates layers of light. This can be achieved by providing a minimal amount of ambient lighting for pedestrian areas and street lighting. Lighting key features, building facades, trees and other vertical surfaces adds interest and assists in the detection and identification of potential intruders or other hazards such as stairs, street curbs and other obstacles.
Using luminaires that are shielded to reduce or eliminate uplight not only aids in achieving the LEED credit for reducing light pollution, but also reduces glare. Glare obscures images on a security camera and dominates the field of vision, therefore making it more difficult to identify a potential intruder. A lighting designer can assess the lighting needs for a project, provide recommendations that help in attaining LEED certification, and perform point-by-point calculations that demonstrate the horizontal illuminance values to meet LEED requirements at the property boundary.
LEED recognizes four lighting zones:
LEED strategies to improve indoor air quality call for keeping fresh air intakes a minimum of 25 to 40 feet from sources of contaminants. Administrators must be aware of the potential threats from terrorists who might try to introduce chemical, biological, or radiological compounds into a building via fresh-air intakes. For this reason, air intakes on buildings should be placed at the highest practical level.