June 18, 1957

The Nevada Test Organization today issued a strong warning to persons living in the nearby region concerning eye hazard from the flash of light which will result from a test scheduled for late next week. One of the shots now scheduled to be ready for firing June 27, will be suspended from a balloon at a height of 1,500 feet, and it will have an above nominal yield. It will be fired in the semi-darkness of dawn. Safety personnel estimate that the fireball will be sufficiently intense to present an eye hazard to those who have a direct view of the fireball.

They estimate that the fireball will retain such intensity until its upper edge has risen to above 2,000 feet. The eye hazard will of course be more serious close to the Nevada Test Site, but it is estimated that some retinal damage could be experienced up to 60 miles away.

Line-of-sight studies have been made from topographic maps to determine points at which the fireball will be directly visible to occupants of vehicles within 60 miles. With the cooperation of state and county officials, road blocks will be established 30 minutes before shot times to bracket the following highway points.

In addition, there will be direct line-of-sight to all higher peaks within a 60 mile radius. The warning is directed specifically to observers on Angels Peak, Charleston Peak and the elevations from which Groom and Lincoln mine people are accustomed to view shots.

Drivers of vehicles will be requested to stop their cars until after the shot, and not to look toward the test site for a few seconds after the shot even though they may be wearing sun glasses. Observers on higher elevations are cautioned not to look toward NTS until some seconds after the shot, even though they may be wearing sun glasses.

All observers are again cautioned not to look toward NTS at shot time with any optical aids such as binoculars or rifle scopes. Such aids can greatly instensify eye injury.

In addition to the hazard from a direct view of the fireball, all drivers of vehicles and all observers within in 60 miles are cautioned that the indirect light will also be intense. It will not only startle a driver but it could cause dark spots or otherwise impare vision for a brief period.

This shot will be identified in pre-shot announcements. Test Organization monitors stationed in 17 community zones surrounding NTS will also know when it is being considered for firing and will advise local residents.

The second shot scheduled to be ready June 27 and to be fired from a tower will not present the same line-of-sight hazard because of its lower positioning. It will, of course, develop sufficient light to cause dark spots before the eyes of relatively close observers or to startle drivers.

[Press Release: Detonation]