Availability of Hats Online in the United States that Meet Sun Protective Recommendations

Abstract

OBJECTIVE

The objective of this study is to determine the likelihood for online consumers seeking hats for sun protection in the United States (US) successfully finding one that meets the recommended criteria for adequate UV protection and whether UPF claims made by these products are reliable indicators of this protection based on materials, structure, and design.

METHODS

Online US consumer experience was simulated to identify the top 20 hats targeting consumers seeking sun protection. Specific details were evaluated for the top 20 products identified based on the volume of product occurrences identified as key markers for ultraviolet (UV) protection including the hat style, brim length, UPF claims, presence of ventilation eyelets or mesh, and presence of a reflective undersurface.

RESULTS

Although 90 percent of hats marketed for use in the sun made UPF claims, there was a 60 percent probability of finding a hat that conformed to stringent UPF standards for hats set forth by UK and Australian testing standards for UPF claims to be made by hats to be used for sun protection factoring in materials, structure, and design.

CONCLUSION

Given the lack of conformity for UPF testing and 33 percent of hats failing to meet criteria for adequate sun protection based on materials, structure, and design, UPF claims for hats sold in the US online are not a reliable indicator for sun protection. Recommendations for hats for UV protection should focus on crown coverage, circumferential brim with length of at least 2.75”, materials with minimal disruption, and not UPF claims.

Hats are routinely referenced as a recommended method for outdoor ultraviolet (UV) protection in addition to traditional sunscreen products, offering potential coverage to high-risk areas for sun exposure such as the face and neck.^1–3 The materials, structure, and design of the hat ultimately dictate the ability of a hat to provide this protection to the areas covered as well as to areas possibly shaded by the hat.⁴ Several health societies recommend the use of a wide brimmed hat (WBH) recognizing the added shade the brim can offer, however most do not offer recommendations to consumers to seek out hats with ultraviolet protection factor (UPF) claims.^1–3

Manufacturers often make use of the UPF claim attached to products such as hats and clothing in an attempt to reference the reduction in UV transmittance offered by the product.⁵ Some testing protocols for UPF focus on the textile alone of the hat without consideration to design details while others may factor these in. The United Kingdom (UK) and Australia have defined stringent standards for hats to meet for UPF claims to be used in the sun recognizing the distinct purpose these products serve in UV protection. To add UPF claims to hats, testing includes the materials used in the new and unused state as well as the structure of the hat as WBH or a Legionnaire style hat (LH) with defined minimum brim length, and design details including avoidance of disruption in the materials.⁶ Prior studies demonstrated that most hats found in stores failed to meet these standards in Ireland and Australia.^7,8 In the United States (US), UPF claims tend to focus on the materials alone without consideration to structure and design.

This study sought to determine the likelihood for online consumers seeking hats for sun protection in the US successfully finding one that meets the UK recommended criteria for adequate UV protection and whether UPF claims made by these products are reliable indicators of this protection based on materials, structure, and design.

METHODS

The top 20 hats available online based on search performance were identified and reviewed for their UV protection features, claims, and validation of these claims. Simple statistics were used to analyze the data to determine probabilities associated with each feature. This online study did not utilize human subjects and exempt from institutional review board approval.

Identification and selection of keywords. To simulate online consumer behavior seeking hats as sun protection, 11 search terms were determined by the volume of keyword searches using a search engine optimization (SEO) tool on dates July 10, 2024, and July 11, 2024 and top ten chosen for further analysis in this study. The search terms selected were based on use scenarios to favor users seeking hats for use in the sun as opposed to other environmental uses (Table 1).

TABLE 1.

Keyword phrases and associated volume of average monthly searches as determined by Ubersuggest keyword tracking tool

SEARCH TERMS	UBERSUGGEST (VOLUME)*
Summer hat	110,000
Golf hat	60,500
Sun hat	40,500
Fishing hat	22,200
Beach hat	14,800
Sun protective hat	6,600
Gardening hat	4,400
Outdoor hat	2,900
UPF hat	1,000
UV hat	1,000
Pool hat	880

Online keyword search tool on dates July 10, 2024, and July 11, 2024 was utilized to determine top keyword phrases for hats for sun protection based on volume.

*Ubersuggest volume is based on the number of searches a keyword has in a particular month.

Identification and selection of products.Each search term was used in Google and Amazon search engines from July 12, 2024 through July 16, 2024 on two separate computers with personalized searches set to “off”, country set to the “United States”, and language set to “English”. Twenty hats were selected based on highest volume of product occurrences for further evaluation with details recorded for each product including the hat style, UPF rating if claimed by the manufacturer and testing protocol, brim length, presence of a cape to cover neck, presence of eyelets or mesh, and presence of a reflective undersurface.

RESULTS

Approximately 263,900 average monthly users of Google searching the top ten keyword phrases in the US in the English language were noted. (Table 1) Of the top 20 products reviewed, one was an LH style hat, three were crossover styles of WBH and LH, 16 were WBH (this includes one visor). Crossover style for WBH and LH was designated for hats that offered a wide brim along with a cape to hang over the neck but failed to provide direct blockage of the ears from direct contact with materials similar to an LH style hat. (Figure 1)

FIGURE 1.

Design of WBH, WBH/LH crossover (hats that offer a wide brim along with a cape to hang over the neck but fail to provide direct blockage of the ears similar to an LH style hat), and LH style hats (provides direct coverage for ears and posterior neck but fails to provide coverage for cheeks similar to baseball style hat)

Eighteen (90%) hats made UPF claims of at least a value of 40 and 80 percent made claims to a UPF of 50+ (Table 2). There was no designation of testing protocol used to determine UPF value for any on websites or upon inquiry through email. One hundred percent of these UPF rated products had a brim length of at least 2.75 inches. The only true LH style hat claimed a UPF 40+ with a brim length of 2.75”. The use of ventilation eyelets remained under a total of 10 eyelets for all WBH, LH, and WBH/LH that made use of eyelets, however the 3 (15%) made use of ventilation mesh and 2 (10%) had holes to accommodate hair or the crown of the scalp resulting in large disruptions in coverage. There were no hats evaluated with a reflective undersurface.

TABLE 2.

Distribution of hats based on type and designated protective criteria

HAT TYPE	NUMBER OF HATS	UPF 50+ ‡	BRIM LENGTH AT LEAST 2.75" ‡	CAPE COVERS NECK ‡	MINIMAL DISRUPTION WITH EYELETS, HOLES, OR MESH ‡ *	PROBABILITY OF MEETING UK & AUSTRALIAN STANDARD FOR UPF CLAIMS**
WBH ‡	16	81.25% (13)	100% (16)	N/A	87.5% (14)	0.71
WBH/LH ‡	3	100% (3)	100% (3)	100% (3)	0% (0)	0
LH ‡	1	0% (0)	100% (1)	100% (1)	100% (1)	0
Meets criteria	20	80% (16)	100% (20)	100% (4)	75% (15)	0.60

Probability of finding hat that meets designated criteria listed as a percentage with volume of occurrences meeting this criteria noted in parentheses.

UPF: ultraviolet protection factor; UK: United Kingdom; US: United States; WBH: wide brimmed hat; LH: legionnaire style hat

*Minimal disruption characterized by no more than a maximum of 10 ventilation eyelets in the textile smaller than 3mm each and no closer than 10 mm distance from each other

**UPF testing protocol data not available. This data is based on an assumption of UPF testing accuracy

‡UK Standard 8466:2006 criteria to meet

The likelihood of finding a WBH, LH, and any hat that met the criteria for the UK and Australian standards for adequate UV protection was calculated by multiplying the probabilities of each individual criterion being met for each type of hat and for hats overall, assuming that each criterion is independent of the others (Table 2).

DISCUSSION

With practicality and comfort, certain demographics, such as older males, tend to rely on hats more heavily than other methods for sun protection.⁷ UV rays can reflect, absorb, and transmit across the materials of a hat. The more direct coverage offered by a hat based on the tightness of the weave of the materials and minimal disruption of the materials based on design and indirect protection through shade offered by brim based on structure means the less potential UV damage seen. Although more than 76 percent of adults seeking sun protective clothing surveyed in a study by Gambichler et al prefer products labeled with a UPF claim, the American Academy of Dermatology (AAD), Skin Cancer Foundation (SCF), and American Cancer Society (ACS) do not make specific recommendations for seeking UPF claims for hats^1,2,3,9 (Table 3).

TABLE 3.

Design specification recommendations for hats to be used in the sun by various US based health societies

FEATURES	AMERICAN ACADEMY OF DERMATOLOGY (US)	SKIN CANCER FOUNDATION (US)	AMERICAN CANCER SOCIETY (US)
Hat style	WBH	WBH	WBH or LH
Brim length	Not specified; "Cover neck and ears"	"At least 3 inches"	"At least 2 to 3 inch brim"
UPF rating	Not specified	Not specified	Not specified
Weave of fabric	Not specified	"Tightly woven"	Not specified
Length of cape	Not specified	Not specified	7" cape for LH (shade cap)
Ventilation eyelets	"No holes in fabric"	Not specified	Not specified
Avoid reflective undersurface	Not specified	Not specified	Yes

UPF: ultraviolet protection factor; US: United States; WBH: wide brimmed hat; LH: legionnaire style hat

Materials. Polyester, cotton, and elastane as well as mesh and straw are often found in the materials for hat construction. Ultimately the ability of these materials to impact UV transmittance is based on the how these fibers are brought together leading some authorities to reference the need to seek “tightly woven” materials.⁵ Mesh and straw hats that are loosely woven, for example, can offer some protection but may allow more UV penetrance than a cotton twill hat.¹⁰ There is no accepted definition for how consumers can evaluate a hat for the tightness of the weave of the materials other than perhaps common sense of not noting obvious gaps in the materials used. UPF testing protocols are intended to provide consumers with added assurance of protection from the materials used by providing data on the ability of these materials to reduce UV transmittance to the skin. The testing includes an evaluation of both UV-A and UV-B penetration.

In the US, the UPF testing protocol AATCC 183 is often used for hats. This protocol focuses solely on the main material in a hat to test UV-A and UV-B transmittance in the new and unused state without consideration to the final hat structure and design details such as mesh or eyelets.¹¹ Testing protocols in the UK (BS 8466:2006) and Australia (AS/NZS 4399:2017) are more stringent for a hat to be considered for use as sun protection. The focus is on materials, structure (WBH or LH), and design with no more than a maximum of 10 ventilation eyelets in the textile smaller than 3mm each and no closer than 10mm distance from each other permitted.^7,8 To meet testing standards, a UPF of 50+ for the materials is required. For WBH, the 360 degree brim length of at least 7cm/2.75 inches is required while for LH the brim should extend at least 7cm/2.75 inches anteriorly with one continuous piece of textile for posterior coverage.⁶

None of the hats we evaluated offered testing protocol details, however 90 percent made a claim of a UPF of at least 40 and 80 percent with a UPF of 50+. With only 60 percent of the hats evaluated meeting the UK and Australian standards factoring in structure and design of the final hat, 33 percent of products with UPF claims evaluated did not meet the design specifications noted for adequate sun protection.

Structure. The materials of the hat can offer direct protection for skin that comes into direct contact with the hat, however, the ability to provide additional coverage beyond the skin covered requires structural features such as a brim or flaps. WBH for UV protection is the most common design recommended by the AAD, SCF, and ACS. The criteria to define a WBH, however, are not consistently clear in terms of brim length, crown coverage, or circumferential brim.

Hats, regardless of brim size, can fail to achieve adequate UV protection for the face with a maximum predictive protection factor of about 76 percent reduction in UV exposure based on angles of UV exposure.⁴ Although larger circumferential brims can offer more UV protection, these are not practical for routine use. There are a wide range of recommendations offered by various health societies on brim size from vague mentions of the need to cover ears and neck, to at least three inches, and at least 2 to 3 inches by the AAD, SCF, and ACS, respectively.^1–3 Reference to 4” brims has even been made by some sources while others recommend at least 3” for suitable coverage around the nose and cheeks based on angles of UV exposure.^10,12 The data to support the UK and Australian standards for a brim length of at least 7cm (2.75”) is unclear.

The lack of consensus is reflective of the challenges faced in accounting for angles of UV exposure recognizing that relying on shade offered is inherently not reliable. All of the hats evaluated offered a brim length of at least 2.75” although one did not offer a full circumferential brim. Practically speaking, the presence of a circumferential brim of at least 2.75” likely accounts for added ear protection and an attempt at additional nose and neck protection.

LH style hats are similar to a baseball cap in terms of structure with the addition of a cape for direct protection of the ears and neck in addition to a frontal brim for potential nose coverage. While the WBH/LH crossover styles offer some additional shade to the cheeks, a true LH style hat may not do so. A baseball hat does not offer much UV protection to the cheeks.¹³ The ability of an LH style hat to offer cheek protection will vary based on length and extent of anterior brim.

Recommendations for LH style hats were only noted by the SCF.¹ Although the closer skin contact with the materials of the hat should offer more UV protection for ears and neck, only 5 percent of hats evaluated were true LH style.

Design. It is unclear the extent to which the disruption in the textile surface by the presence of mesh, eyelets, and other holes in fabric impact UV exposure to these areas of skin and hair covered scalp. These design features are routinely added to support the comfort of the wearer either from sweating or to accommodate hair but will also permit added UV transmittance.

UPF testing protocols in the US likely apply to the main materials the textile is created from without taking into account variations in protection offered by areas covered by mesh, eyelets, or holes unless specified. The UK and Australian standards do specify the number and maximum size for ventilation eyelets. With 25 percent of products containing these gaps in textile coverage, this criteria should be factored into product recommendations to reduce the chances of faulty protection from UV sources.

There are several limitations to this study. Online search keywords and keyword phrases can produce variations in search results with algorithm changes over time, while sponsored products and those with high volume of product reviews or highlights as “best sellers” may influence purchases. Another limitation is the comparison of the data from this online shopping experience to that of in person shopping from other studies. The online shopping experience for sun hats will inherently be a targeted approach and vary considerably from an in-person experience which relies heavily on inventory in particular shopping centers as well as geographic location to serve the needs of the area located.

CONCLUSION

Although 90 percent of hats marketed online for use in the sun in the US make UPF claims, only 60 percent of these hats met structure and design recommendations for adequate UV protection found in UK and Australian UPF testing protocols for sun hats. With the lack of clearly defined guidelines to determine UV protection offered by hats, misconceptions amongst consumers regarding the actual UV protection offered may risk a false sense of security during times of high UV exposure. Given the lack of conformity for UPF testing, physician recommendations for hats for UV protection should focus on crown coverage, circumferential brim with length of at least 2.75”, materials with minimal disruption, and not UPF claims.