Two bombs detonated within seconds of each other near the finishline of the Boston Marathon, killing three and injuring morethan 180 people. Gunmen killed 12 at the office of a Frenchsatirical magazine.

A gunman killed nine in an attack at Emanual African MethodistEpiscopal Church in Charleston, S.C. Another gunman killed fourMarines and a Navy sailor at two locations in Chattanooga,Tenn. A man flew his single engine plane into the Austin,Texas, IRS building, killing himself and one IRS employee andinjuring 13 others.

[Related: Here are the 10 worst terrorist attacks of all timein terms of insured losses]

These incidents are just a few examples of acts of terrorism andterrorism-related violence that continue to increase worldwide. Andrecent lone-wolf attacks keep the threat of terrorism on the mindsof U.S. business owners and executives.

While acts of terrorism and political violence are a significantthreat to a company's global operations, the January authorizationof the Terrorism Risk Insurance Program ReauthorizationAct of 2015 (TRIPRA) helped prevent disruption and providedgreater certainty to terrorism insurance markets in the UnitedStates, according to Marsh's "2015 Terrorism Risk Insurance Report." Thereport summarizes TRIPRA, provides benchmarking related toterrorism insurance take-up rates and pricing, and offers riskmanagement solutions for terrorism risks that will be useful fororganizations even if they purchase terrorism insurance.

Here are 16 key points insurance agents and risk managers needto understand about protecting a company's bottom line againstterrorism and terrorism-related risks.

An FBI investigator investigates the scene of a shootingoutside a military recruiting center on Friday, July 17, 2015, inChattanooga, Tenn. Muhammad Youssef Abdulazeez of Hixson, Tenn.,attacked two military facilities in a shooting rampage that killedfour Marines. (AP Photo/John Bazemore)

1. U.S. government terrorism insurance program extendedthrough 2020

The enactment in the U.S. of TRIPRA through 2020 brought greatercertainty to organizations that depend on terrorism coverage andprevented any short-term increase in pricing that may have beencaused by the law's lapse.

[Related: Better late than never: Obama signs TRIA intolaw]

In this Feb. 18, 2010, file photo, smoke billows from aseven-story structure after Joseph Stack III crashed his smallplane into an IRS office building in Austin, Texas. (APPhoto/Jack Plunkett, File)

2. Terrorism insurance take-up rates have remainedrelatively stable since 2009

Terrorism insurance take-up rates—the percentage of companiesbuying property terrorism insurance—dropped off toward the end of2014 due to the uncertainty stemming from TRIA's pendingexpiration. However, Congress passed TRIPRA in early 2015 andbuyers of terrorism insurance have generally experienced afavorable rate environment that is expected to continue barringunforeseen events.

Police close off a section of Calhoun Street near theEmanuel AME Church following a shooting Wednesday, June 17, 2015,in Charleston, S.C. (AP Photo/David Goldman)

3. Captives

Although organizations can benefit from captive insurancecompanies' ability to access the federal terrorism insurancebackstop, few U.S. captives used TRIA for that coverage in 2014. Ofthe 324 U.S.-domiciled captives that Marsh managed in 2014, 83(22%) accessed TRIA for property coverage, writing terrorismcoverage for conventional perils and for nuclear, biological,chemical and radiological perils that are commonly excluded bycommercial insurers.

Organizations should work with their insurance brokers toevaluate whether using a captive for TRIPRA could provide a moreeffective solution for managing terrorism exposures.

Smoke and flames billow from the World Trade Center towersin this Sept. 11, 2001, file photo. (AP Photo/Chao SoiCheong/FILE)

4. Large companies are more likely topurchase property terrorism insurance and to see the lowest cost asa percentage of overall property premiums

Median rates for the largest companies remained at $18 permillion in 2014. No industry sectors showed decreases in the costof terrorism insurance as a percentage of property premiums.

In this Oct. 10, 1995, file photo, federal investigatorssearch for evidence at the scene of the Amtrak Sunset Limitedwreckage near Hyder, Ariz. The FBI announced on Friday, April 10,2015, a $310,000 reward for information leading to an arrest forthe sabotage of an Amtrak train that derailed nearly 20 years ago.The Sunset Limited passenger train plunged into a dry gulch,killing a crewman and injuring 78 people about 70 miles outsidePhoenix in the twilight hours of Oct. 9, 1995, while heading fromMiami to Los Angeles. (AP Photo/Eric Drotter, File)

5. Education organizations had the highest take-up ratesfor terrorism insurance in 2014

Among industry sectors, financial institutions, real estate andtechnology/telecommunications companies had the next highesttake-up rates among the 17 industry segments surveyed.

Manufacturing, chemicals and energy/mining were among theindustry segments with the lowest take-up rates.

People rush to the scene of an explosion at the CentennialOlympic Park in Atlanta early Saturday, July 27, 1996. A firedepartment spokeswoman said 150 to 200 people were injured when theexplosion struck a tower near a stage where thousands of revelerswere watching a concert at about 1:15 a.m. ET. (AP Photo/ACOGPOOL)

6. Political violencecoverage

Political violence insurance (PVI) provides coverage forterrorism and for exposures that are typically excluded withinstandalone terrorism policies, such as strikes, riots, civilcommotion, rebellion, revolutions, war, civil war andinsurrection.

Consideration of PVI is recommended for global insuranceprograms with significant emerging market exposures. Policiesshould be coordinated with property and standalone terrorismpolicies as well as local insurance pools.

In this image from video provided by WBZ TV, a bomb explodesnear the finish line of the Boston Marathon in Boston on Monday,April 15, 2013. (AP Photo/WBZTV)

7. The maximum achievable limits in the standaloneterrorism insurance market are approximately $4.3billion

Available capacity is significantly lower for exposures in thecentral business districts of Tier 1 cities, which include Atlanta,Boston, Chicago, New York City, San Francisco and WashingtonD.C.

One of the blast sites on Boylston Street near the finishline of the 2013 Boston Marathon is seen in Boston, Tuesday, April16, 2013, one day after bomb blasts killed three and injured morethan 140 people. (AP Photo/Elise Amendola)

8. A higher percentage of companies inthe Northeast—74%— purchased property terrorism insurance than inany other region of the U.S.

This is likely due to the Northeast's concentration of largemetro areas and the perception that major cities may be at higherrisk for a terrorist attack.

The South and West saw the lowest take-up rates in 2014, both at54%.

Flag on a building across the street from Ground Zero, WorldTrade Center, on Sept. 20, 2001, in New York. (LarryBruce/Shutterstock)

9. Property terrorism insurance ratestypically decrease as the size of the companyincreases

This generally reflects overall insurance pricing patterns:Larger companies typically purchase more insurance, which leads tolower rates when compared with smaller companies. The cost asa percentage of overall property premiums was similar for allcompanies, regardless of total insurable value (TIV).

Medical workers aid injured people at the finish line of the2013 Boston Marathon following an explosion in Boston, Monday,April 15, 2013. (AP Photo/Charles Krupa)

10. Overall, construction companiespaid the most for their terrorism insurance in 2014, at a medianrate of $77 per million

Median property terrorism insurance premiums decreased or stayedthe same in 2014 for nine of 17 industry categories. Ratesincreased the most for media, hospitality and gaming, andconstruction organizations.

Energy and mining, public entity and nonprofit, and lifesciences sectors experienced the most significant decreases.

In this May 5, 1995, file photo, a large group of the searchand rescue crew attends a memorial service in front of the AlfredP. Murrah Federal Building in Oklahoma City. The blast killed 168people—including 19 children—injured hundreds more and causedhundreds of millions of dollars in damage to structures andvehicles in the downtown area. (AP Photo/Bill Waugh, File)

11. Companies in the Midwest paid thelowest rates, on average, for property terrorism insurance in2014

Based on median premium rates, terrorism insurance was mostexpensive in the South at $31 per million.

An FBI crime scene investigator documents evidence outsidethe Curtis Culwell Center in Garland, Texas, on May 4, 2015. APhoenix-area man has been charged with helping plan the attack on aprovocative Texas cartoon contest featuring depictions of theProphet Muhammad that ended with the two shooters' deaths. (APPhoto/Brandon Wade, File)

12. Favorable pricing conditions

The authorization of TRIPRA, robust flows of capital in both theinsurance and reinsurance segments, and moderate CAT losses, havecombined to create pricing conditions favorable to mostinsureds.

Most insureds are seeing rate and premium decreases as well ascoverage improvements, mostly driven by a competitivemarketplace.

Demolished building after terror attack and bomb explosionin Levent HSBC Bank on Nov. 20, 2003, in Istanbul, Turkey. Theblast killed 30 people and wounded 400 others. (Photo: Prometheus72/Shutterstock)

13. The terrorism reinsurance market

TRIPRA capacity remains crucial to the insurance industry asprivate market reinsurance capacity is not sufficient to providethe same level of capacity as that offered by TRIPRA.

With a multi-year TRIPRA solution and incremental changeslimiting the government's potential exposure over time, it'santicipated that the reinsurance market will continue to grow,develop and provide capacity for ceding companies that don't wantto increase their net exposure to terrorism.

CID, police and prosecution at the site after the explosionthat was targeting the Interior Minister in Mostafa el-Nahas St. inNasr City, Cairo, Egypt, on Sept. 5, 2013. (Photo: MohamedElsayyed/Shutterstock)

14. Terrorism pools

Terrorism pools have been created internationally to helporganizations manage the global threat of terrorism. Typically,each pool requires a declaration by the national government that aterrorist event has occurred to trigger coverage.

In the countries in which compulsory or optional terrorismreinsurance pools exist, property insurance policies can beextended to include terrorism coverage in accordance with the localpool.

(Photo: specnaz-Shutterstock)

15. Terrorism risk modeling and other analyticaltools

Terrorism risk modeling and other analytical tools can helporganizations determine how much coverage to purchase and whethercapacity is in short supply, or not. Such models can helporganizations better understand their financial exposure; determineappropriate insurance deductibles and limits; optimize risk financestrategies; rate the terrorism risk to negotiate insurancepremiums; understand the risk's potential impact on capital;prioritize risk mitigation strategies; build efficient businesscontinuity plans; and understand the correlation and potentialbenefits of diversification among sites, locations and regions.

(Image: Shutterstock)

16. Terrorist attack business continuity planrecommended

Organizations that review and update their business continuityplans to ensure they are prepared in the event of a terroristattack can improve their risk profile for underwriters. To ensurethat business continuity plans help preserve and protect operationsand people, organizations should assess their plans and validatethem through training and exercises. Such measure can helporganizations think through their terrorism-related risks and get abetter understanding of their exposures.

[Related: How TRIA can save sports, skyscrapers, andsubways]