Core Viewpoint - The article highlights the potential fire hazards posed by glass products, such as empty bottles and mirrors, when exposed to sunlight during the summer months, emphasizing the need for caution in their storage and handling [3][9][17]. Group 1: Incidents of Fire Caused by Glass Products - On June 4, a storage compartment in Beijing caught fire due to sunlight refracting through empty glass bottles, igniting surrounding flammable materials [3]. - A similar incident occurred in Fujian, where sunlight focused through a double-sided mirror ignited a promotional flyer, leading to a fire that destroyed items in the store [5][6]. - In May of the previous year, a backyard fire in Zhejiang was traced back to 80 crystal balls that reflected sunlight, igniting nearby cardboard boxes [8]. Group 2: Other Fire Hazards in High Temperatures - A fire in a vehicle in Beijing was caused by sunlight heating water bottles placed on top of the truck, which ignited surrounding materials [11]. - The structure of common items like bottled water and reading glasses can act as convex lenses, concentrating sunlight and increasing temperatures, which can lead to fires [13]. - Firefighters conducted experiments showing that items like lighters and spray cans can explode when left in a car under direct sunlight, with significant temperature increases observed [15]. Group 3: Safety Recommendations - It is advised to keep items such as magnifying glasses, bottled water, and other glass products away from direct sunlight and flammable materials [17]. - Specific caution is recommended for items like lighters, power banks, and aerosol sprays, which should not be left in vehicles during hot weather [17].

Core Points - The article highlights the risk of fire caused by glass objects under sunlight, comparing them to "small grenades" due to their potential to ignite surrounding materials [1][4] - A recent incident in Beijing's Huairou district involved a storage compartment catching fire due to improperly stored glass and paper materials, demonstrating the dangers of mixed storage [3][4] - The phenomenon is explained through the lens of the magnifying effect, where sunlight can be focused by glass objects, leading to ignition of flammable materials [6][11] Summary by Sections - **Incident Description** - A fire occurred on June 4 at a street shop's storage compartment, which was quickly addressed by firefighters [1][2] - The compartment contained only cardboard and miscellaneous items, with no active production or electrical wiring present [3] - **Cause of Fire** - The investigation revealed that the storage was overcrowded with mixed items, including empty glass bottles and paper products, which contributed to the fire risk [3][4] - Sunlight entering through gaps in the locked compartment door focused through glass items, igniting nearby combustible materials [4][6] - **Similar Cases** - Other incidents were cited, such as a fire caused by a double-sided mirror reflecting sunlight onto a table, and another involving crystal balls igniting cardboard in a backyard [6][9][7] - **Fire Prevention Tips** - Recommendations include avoiding placing glass objects in direct sunlight and keeping them away from flammable materials [13] - Emphasis on educating children about the dangers of using magnifying glasses and similar items [13]