Communicating Severity of Hazard with the Signal Word on a Safety Sign

An experiment examined five signal words on safety signs for effectiveness at communicating information about severity of a hazard. Perceived severity was rated by 59 college students for the signal words Deadly, Danger, Warning, Caution, and Notice. Results indicated that Deadly communicated the highest ratings for severity. Danger was second. Warning and Caution were tied for third. The lowest ratings were for Notice.

Effectiveness of Colors used on Safety and Health Signs for Communicating Severity of Injury

Signs are used extensively in workplaces and on products to identify hazards and provide instructions for appropriate behavior. A fundamental element of these signs is the signal-word panel located at the top of the sign. The colors and words in this panel are intended to convey information about the hazard identified. One type of hazard information concerns the severity of injury/illness associated with the hazard. The standard of the American National Standards Institute (ANSI) for facility signs uses three severity categories: 1) death or serious injury, 2) minor or moderate injury, and 3) property damage. The standard specifies which signal-word panel format, including color, to use based in part on the severity category. The purpose of this study was to determine if college students associate color with severity. The sample population consisted of 59 students tested in nine small groups. Twelve signs were shown to them in random order. Five of the signs had a color for the background of the signal-word panel. The colors were red, orange, yellow, blue, and gray. The signal word was a nonsense word and the text panel contained repetitions of the letter x in sentence format. Subject rated their impressions of the colors using two ordered rating scales for severity. Results indicated that color had a highly significant effect on severity ratings. Median ratings were generally consistent with the ANSI standard, except for orange. Red rated highest on both scales. Blue and gray rated lowest. Yellow and orange were in between red and blue. According to the ANSI standard, orange should indicate the same severity as red. These results indicated that orange was associated with less severity than red. Apparently, the ANSI standard's use of orange to identify a hazard associated with death or a serious injury is questionable.

Pool Irradiator Safety Review for Genesis-II Systems

This report examines the Genesis II irradiator made by Gray*Star Incorporated, Mississippi Department of Health radiation safety regulations, and Nuclear Regulatory Commission (NRC) inspection guidelines for irradiators. The purpose for this report is to evaluate any hazards which may lead to a catastrophic water loss, evaluate protective action distances during a reduced shielding situation, and evaluate the safety engineering measures incorporated by Mississippi and Federal regulations to ensure the mitigation of risk for pool irradiators. Due to safeguard controls prohibiting release of precise data on emergency response measures and radioactivity of the isotopes utilized this report will be focused on regulations mandating specific engineering controls and manufacturer recommended guidelines for best practices.

Stairway Uniformity Measurement: What Lateral Location Should Be Measured?

BACKGROUND: This project addressed an unresolved issue involving measurement methods for determining step uniformity. Leading experts on stairway safety agree that lack of step uniformity within a flight contributes to risk of missteps. A relatively new method for precisely measuring step dimensions is the nosing-to-nosing method. An issue in applying the method is lack of agreement on the lateral location to make the measurements. That location depends on where stairway users ascend and descend relative to the width of the steps. A prior investigator examined people descending to determine the lateral distance between the handrail center and the mid-line of the person’s body. He found the median was 44 cm. AIM: The two objectives of the experiment were to: (1) determine if a different set of stairway users will have the same median lateral distance from the handrail as those described in the prior observational study, and (2) determine if the lateral distance of participants is affected by their direction of travel and use of a handrail. METHODS: The investigators established visible distance markers on one stairway in a campus building and videotaped volunteer students ascending and descending the flight of stairs. Each of the 16 participant ascended with and without using the handrail, and each descended with and without using the handrail. Images were printed and analyzed to determine their lateral distance between the inner edge of the handrail and a point midway between the participant’s knees. Results were analyzed statistically to test hypotheses corresponding to the two objectives. RESULTS: The previous study found a median lateral distance of 44 cm when measured from the center of the handrail. Using comparable data, the median found in this study was 25 cm. Results of this study indicated that lateral distance from the handrail is significantly affected by the direction of travel and by use of the handrail. The greatest lateral distance was for ascending with the handrail. The shortest lateral distance was for descending without the handrail. VALUE: Committees develop and periodically revise standards for stairways leading to fire exits and workplace facilities. The practical value of this project is providing empirical evidence that standard developing committees may consider when convening to update their requirements and guidelines on how to measure step uniformity.