Technical Investigation

of the May 22, 2011,

Tornado in Joplin, MO

December 10, 2013

NCST Advisory 

Committee Meeting

Recommendations

Joplin Team
Recommendations Related to 

Tornado Hazard Characteristics and 

Associated Wind Field

2
NIST recommends that a capacity be developed and 

deployed that can measure and characterize actual 

near-surface tornadic wind fields for use in the 

engineering design of buildings and infrastructure. This 

would require enhancement and widespread 

deployment of advanced technologies, including 

weather radar. 

Recommendation 1--

3
4

NIST recommends that information gathered and 

generated from tornado events (such as the Joplin 

tornado) should be stored in publicly available and easily 

accessible databases to aid in the improvement of 

tornado hazard characterization. 

Recommendation 2 --
NIST recommends that tornado hazard maps for use in the 

engineering design of buildings and infrastructure be 

developed considering spatially based estimates of the 

tornado hazard instead of existing point-based estimates 

that produce significantly lower tornado probability of 

occurrence and subsequent risk. 

Recommendation 3 --

5
NIST recommends that new damage indicators (DIs) be 

developed for the Enhanced Fujita tornado intensity scale 

to distinguish between the most intense tornado events. 

Methodologies used in the development of DIs and 

associated degrees of damage should be, to the extent 

possible, scientific in nature with quantifiable results. As 

new information becomes available, a committee 

comprised of public and private entities should be formed 

with the ability to propose, accept, and implement changes 

to the EF Scale. The improved EF Scale should be adopted 

by NWS. 

6

Recommendation 4 --
7

Recommendations Related to the 

Performance of Buildings, 

Shelters/Designated Safe Areas, 

and Lifelines
NIST recommends that nationally accepted performance–based standards 

for the tornado–resistant design of buildings and infrastructure be 

developed in model codes and adopted in local regulations to ensure the 

resiliency of communities to tornado hazards. The standards should 

encompass tornado hazard characterization, performance objectives, and 

evaluation tools. The standards shall require that critical buildings and 

infrastructure such as hospitals and emergency operations centers are 

designed so as to remain operational in the event of a tornado.

8

Risk Cat.* IV Facilities

Risk Cat.* III

Risk Cat.* II

(1) Hardened area, shelter–in–place.

(2) Public shelter.

* Based on ASCE 7–10.

The standards would:

− Prescribe “tornado–

prone areas”

− Specify “design 

tornadoes”

− Prescribe “building 

performance objectives”

Recommendation 5--
9

Recommendation 6--

NIST recommends the development of risk–consistent, 

performance–based tornado design methodologies to 

ensure that all building components and systems meet 

the same performance objectives when subjected to 

tornado hazards.
NIST recommends that: (a) model building codes for new 

buildings require that tornado shelters be designed in 

accordance with the ICC 500 standard; (b) model building 

codes develop and adopt a tornado shelter standard 

specific for existing buildings; and (c) tornado shelters be 

installed in new and existing multi–family residential 

buildings, mercantile buildings, and buildings with assembly 

occupancies located in tornado hazard areas identified in 

the performance–based standards required by 

Recommendation 5.

Recommendation 7--

10
11

Recommendation 8--

NIST recommends the development and implementation 

of uniform national guidelines that enable communities 

to create the safest and most effective public sheltering 

strategies. The guidelines should address planning for, 

siting, designing, installing, and operating public tornado 

shelters within the community. 
NIST recommends that uniform guidelines be 

developed and implemented nationwide for conducting 

tornado risk assessments and designating best 

available tornado refuge areas as an interim measure 

within buildings until permanent measures fully 

consistent with Recommendations 5 and 7 are 

implemented.

Recommendation 9--

12
13

Recommendation 10--

NIST recommends that aggregate, gravel, or stone be 

prohibited as roof surfacing material or roof ballast for 

buildings of any height in tornado–prone areas. that 

aggregate, gravel, or stone be prohibited as roof 

surfacing material or roof ballast for buildings of any 

height in tornado–prone areas.
NIST recommends that enclosures of egress systems 

(elevators, exits) in critical facilities in tornado–prone areas 

be designed to maintain their functional integrity when 

subjected to tornado hazards.

Recommendation 11--

14
15

Recommendation 12--

NIST recommends that owners and operators of existing 

critical facilities in tornado–prone areas perform tornado 

vulnerability assessments and take steps to ensure the 

functionality of (1) backup power supplies (harden the 

protection of emergency backup power, as region–wide 

losses of power due to damage to power transmission 

infrastructure occur frequently in tornadoes), (2) vertical 

movement within the building (elevator equipment and 

shaft enclosures), and (3) means of egress illumination 

(battery–powered lighting in addition to backup power), in 

a tornado event.
Recommendations Related to the 

Pattern, Location, and Cause of 

Fatalities and Injuries, and 

Associated Performance of 

Emergency Communications 

Systems and Public Response

16
NIST recommends the development of national codes and 

standards and uniform guidance for clear, consistent, and 

accurate emergency communications, encompassing alerts 

and warnings, to ensure safe, effective, and timely 

responses among individuals, organizations, and 

communities in the path of storms having the potential to 

create tornadoes.

NIST also recommends that emergency managers, the 

NWS, and the media develop a joint plan and take steps to 

ensure that accurate and consistent emergency alert and 

warning information is communicated in a timely manner to 

enhance the situational awareness of community residents, 

visitors, and emergency responders affected by an event.

Recommendation 13 --

17
NIST recommends that the full range of current and 

next–generation emergency communication “push” 

technologies (e.g., GPS–based mobile alerts and 

warnings, reverse 9–1–1, outdoor siren systems with 

voice communication, NOAA weather radios) be widely 

deployed and utilized, to maximize each individual’s 

opportunity to receive emergency information and 

respond safely, effectively, and in a timely fashion.

Recommendation 14 --

18
NIST recommends research to identify the factors that will 

significantly enhance public perception of personal risk 

and how such knowledge can be better used to rapidly 

and effectively respond during tornadic events.

Recommendation 15 --

19
NIST recommends that tornado threat information be 

provided to emergency managers, policy officials, and 

the media on a spatially resolved real–time basis by 

frequently updating gridded probabilistic hazard 

information that is merged with other GIS information to 

supplement the currently deployed binary warn/no warn 

system.

Recommendation 16 --

20