Core Points - The article discusses the condition known as photokeratitis, which is essentially a sunburn of the eyes caused by excessive exposure to ultraviolet (UV) light [4][10][11] - Symptoms of photokeratitis include redness, pain, tearing, swelling, light sensitivity, a feeling of having something in the eye, and blurred vision [1][2][4] - The article emphasizes the importance of eye protection from UV rays, especially in environments with high UV exposure, such as beaches and high altitudes [8][11] Summary by Sections Photokeratitis - Photokeratitis, also known as ultraviolet keratitis, is an inflammation of the cornea and conjunctiva due to UV exposure, leading to symptoms like headaches and temporary vision loss in severe cases [4][10] - Symptoms typically resolve within hours or days, and immediate rest and artificial tears can alleviate discomfort [4][10] Causes and Prevention - UV rays from various sources, including sunlight, tanning beds, and welding arcs, can cause photokeratitis [6][10] - The article highlights the need for protective measures, such as wearing sunglasses and hats, especially during peak UV hours [11][13] Related Eye Conditions - Pterygium, another UV-related eye condition, has a prevalence of approximately 9.9% in certain regions, characterized by a growth on the conjunctiva that can affect vision [10] - Long-term UV exposure can also lead to macular degeneration, cataracts, and even skin cancer around the eyelids [11][10] UV Light Information - UV light is categorized into three types: UVA, UVB, and UVC, with UVB being the most harmful to the eyes [16][17] - Sunglasses labeled "UV400" can block nearly 100% of UV rays, providing essential protection for eye health [13][11]

Group 1 - The core concept of sunscreen is to protect against ultraviolet (UV) rays, specifically UVA and UVB, with UVB being the primary cause of skin damage [2][3] - Sunscreen is necessary year-round, not just in summer, as UV rays can still be harmful during cloudy days or in indoor environments where UVA can penetrate glass [3][4] - There are two main types of sunscreen: physical (using barriers like hats and clothing) and chemical (using creams and sprays to absorb UV rays) [4][5] Group 2 - It is recommended to combine both physical and chemical sunscreen methods for optimal protection, as each has its advantages and disadvantages [5] - All demographics, including children, need to be mindful of sun protection, with specific recommendations for infants and young children to primarily use physical methods [5][10] - The SPF (Sun Protection Factor) and PA (Protection Grade of UVA) ratings are crucial indicators of a sunscreen's effectiveness, with higher values indicating better protection [6][8] Group 3 - Different environments require different levels of sunscreen protection, with specific SPF and PA recommendations based on activity and exposure [9] - When selecting sunscreen for children, it is advised to choose products with SPF 30 or higher and PA++ or higher, considering their unique skin characteristics [9][10] - The use of sunscreen sprays for children is discouraged due to the risk of inhalation and potential health hazards [12][13] Group 4 - Consumers should be cautious when purchasing sunscreen products, ensuring they check for proper labeling, SPF and PA values, and ingredient suitability for their skin type [14][15] - Proper application techniques are essential for effective sun protection, including applying sufficient amounts and reapplying every two hours during outdoor activities [15] - Sunscreen should be removed at night to prevent skin irritation, with specific cleaning methods recommended for different types of sunscreen [17]

进入夏季 紫外线逐渐增强 要想保护皮肤 做好防晒是关键 阳光强烈的晴天要防晒 那么阴天没阳光 还需不需要防晒呢？ 一起来看↓ 1 == r and 202 1|终结站 紫外线是导致皮肤晒伤、 老化和黑色素沉积的主要 原因之一。到达地面的太 阳光中的紫外线主要分为 长波紫外线(UVA)和 中波紫外线(UVB)。 不同的防晒指标是啥意思？ SE KE J SPF15：可阻隔约93%的UVB（ 计算公式：1－1/15≈93%） SPF30：可阻隔约97%的UVB（计算公式：1－1/30≈97%） SPF50：可阻隔约98%的UVB（计算公式：1－1/50≈98%） 防晒产品包装上通常标有PA和SPF两个指标，它们是科学选择防晒产品的重要参考指标。 PA是衡量防晒产品对长波紫外线（UVA）防护能力的指标，分为三个级别（以"+"号数量表示防护强度，"+"越多效果越强）： PA+：有效防护UVA（防护时长2~4小时） PA++：较有效防护UVA（防护时长4~8小时） PA+++：非常有效防护UVA（防护时长8小时以上） SPF是衡量防晒产品对中波紫外线（UVB）防护能力的指标。SPF值代表皮肤在紫外线照射下的延迟晒红时间 ...