Search Tips
sorted by
30 shown of 115 entities
The girl child 1998, para. 6d
- Paragraph text
- [Calls upon all States and international and non-governmental organizations, individually and collectively:] To give attention to the rights and needs of adolescent girls, which call for special action for their protection from sexual and economic exploitation and abuse, harmful traditional and cultural practices, teenage pregnancy and vulnerability to sexually transmitted diseases and human immunodeficiency virus/acquired immunodeficiency syndrome and for the development of life skills and self-esteem, reaffirming that the advancement and empowerment of women throughout the life cycle must begin with the girl child at all ages;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Health
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Girls
- Women
- Year
- 1998
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2003, para. 3
- Paragraph text
- Reaffirming that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents,
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2003
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2004, para. 1
- Paragraph text
- Reaffirms that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2004
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2005, para. 1
- Paragraph text
- Reaffirms that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2005
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2006, para. 1
- Paragraph text
- Reaffirms that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2006
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2007, para. 1
- Paragraph text
- Reaffirms that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2007
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2008, para. 1
- Paragraph text
- Reaffirms that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2008
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2009, para. 3
- Paragraph text
- Reaffirming that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents,
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2009
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2009, para. 33b
- Paragraph text
- [Calls upon all States:] To designate, establish or strengthen relevant governmental structures for children, including, where appropriate, ministers in charge of children's issues and independent ombudspersons for children, have mechanisms in place for allowing and promoting the involvement and participation of children in the formulation and implementation of public policies, in particular those designed to meet national goals and targets for children and adolescents, and ensure adequate and systematic training in the rights of the child for professional groups working with and for children;
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2009
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2010, para. 4
- Paragraph text
- Reaffirming that the general principles of, inter alia, the best interests of the child, non-discrimination, participation and survival and development provide the framework for all actions concerning children, including adolescents,
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2010
- Date added
- Aug 19, 2019
Paragraph
The rights of the child 2015, para. 2
- Paragraph text
- Recalling its resolutions 69/158 of 18 December 2014 on protecting children from bullying and 69/187 of 18 December 2014 on migrant children and adolescents,
- Body
- United Nations General Assembly
- Document type
- Resolution
- Topic(s)
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Persons on the move
- Year
- 2015
- Date added
- Aug 19, 2019
Paragraph
Rights of the child: Towards better investment in the rights of the child 2015, para. 21
- Paragraph text
- Calls upon States to consider, as appropriate, promoting, facilitating and funding the meaningful participation and active consultation of children in all the issues affecting them, including in the formulation and implementation of public policies and delivery of services, in particular those designed to meet national goals and targets for children and adolescents, and recognizes the important role played by independent ombudspersons for children, educational institutions, the media, community-based organizations, such as children’s organizations, and parliaments in assuring the meaningful participation of children in these public processes, taking into account the best interests of the child;
- Body
- United Nations Human Rights Council
- Document type
- Resolution
- Topic(s)
- Civil & Political Rights
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2015
- Date added
- Aug 19, 2019
Paragraph
Adolescents and youth 2012, para. 24
- Paragraph text
- Also urges Governments to strengthen basic infrastructure, human and technical resources, and the provision of health facilities so as to improve health systems, particularly for adolescents and youth, and to ensure the accessibility, affordability and quality, especially in rural and remote areas, of health-care services, as well as sustainable access to safe drinking water and basic sanitation, bearing in mind the commitment to halving, by 2015, the proportion of the population without sustainable access to safe drinking water and basic sanitation as a means of fighting waterborne diseases;
- Body
- Commission on Population and Development
- Document type
- Resolution
- Topic(s)
- Equality & Inclusion
- Health
- Social & Cultural Rights
- Water & Sanitation
- Person(s) affected
- Adolescents
- Youth
- Year
- 2012
- Date added
- Aug 19, 2019
Paragraph
Rights of migrant workers in an irregular situation and members of their families 2013, para. 10
- Paragraph text
- Similarly, the International Covenant on Economic, Social and Cultural Rights also provides for a broader range of rights, including the right to strike, the right to freely enter marriage, the right to maternity protection, the right to special protection of children and adolescents, the right to an adequate standard of living including adequate food and clothing, and certain cultural rights. The Convention does not provide for such rights only in relation to migrant workers in a regular situation. In addition, the Covenant recognizes the rights to work, to vocational guidance and training, to form trade unions, to protection of the family, to housing, and to participate in cultural life. The Convention recognizes these rights in relation to migrant workers in a regular situation and members of their families. In addition, most of the economic, social and cultural rights in Part III of the Convention have a narrower scope than their counterparts in the Covenant.
- Body
- Committee on Migrant Workers
- Document type
- General Comment / Recommendation
- Topic(s)
- Economic Rights
- Equality & Inclusion
- Governance & Rule of Law
- Movement
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Families
- Persons on the move
- Year
- 2013
- Date added
- Aug 19, 2019
Paragraph
Children’s rights in juvenile justice 2007, para. 4
- Paragraph text
- [At the outset, the Committee wishes to underscore that CRC requires States parties to develop and implement a comprehensive juvenile justice policy. This comprehensive approach should not be limited to the implementation of the specific provisions contained in articles 37 and 40 of CRC, but should also take into account the general principles enshrined in articles 2, 3, 6 and 12, and in all other relevant articles of CRC, such as articles 4 and 39. Therefore, the objectives of this general comment are:] To promote the integration, in a national and comprehensive juvenile justice policy, of other international standards, in particular, the United Nations Standard Minimum Rules for the Administration of Juvenile Justice (the "Beijing Rules"), the United Nations Rules for the Protection of Juveniles Deprived of their Liberty (the "Havana Rules"), and the United Nations Guidelines for the Prevention of Juvenile Delinquency (the "Riyadh Guidelines").
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2007
- Date added
- Aug 19, 2019
Paragraph
The right of the child to rest, leisure, play, recreational activities, cultural life and the arts 2013, para. 48
- Paragraph text
- Girls: A combination of significant burdens of domestic responsibilities and sibling and family care, protective concerns on the part of parents, lack of appropriate facilities and cultural assumptions imposing limitations on the expectations and behaviour of girls can serve to diminish their opportunities to enjoy the rights provided for in article 31, particularly in the adolescent years. In addition, gender differentiation in what is considered girls' and boys' play and which is widely reinforced by parents, caregivers, the media and producers/manufacturers of games and toys serve to maintain traditional gender-role divisions in society. Evidence indicates that whereas boys' games prepare them for successful performance in a wide range of professional and other settings in modern society, girls' games, in contrast, tend to direct them towards the private sphere of the home and future roles as wives and mothers. Adolescent boys and girls are often discouraged from engaging in joint recreational activities. Furthermore, girls generally have lower participation rates in physical activities and organized games as a consequence of either external cultural or self-imposed exclusion or lack of appropriate provision. This pattern is of concern in the light of the proven physical, psychological, social and intellectual benefits associated with participation in sports activities. Given these widespread and pervasive barriers impeding girls' realization of their rights under article 31, the Committee urges States parties to take action to challenge gender stereotypes which serve to compound and reinforce patterns of discrimination and inequality of opportunity.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Gender
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Boys
- Families
- Girls
- Year
- 2013
- Date added
- Aug 19, 2019
Paragraph
The right of the child to rest, leisure, play, recreational activities, cultural life and the arts 2013, para. 56b
- Paragraph text
- [The obligation to respect includes the adoption of specific measures aimed at achieving respect for the right of every child, individually or in association with others, to realise his or her rights under article 31, including:] Awareness raising: States should invest in measures to challenge widespread cultural attitudes which attach low value to the rights provided for in article 31, including: Measures to challenge the pervasive negative attitudes, particularly towards adolescents, which lead to restrictions on the opportunities for the enjoyment of their rights under article 31. In particular, opportunities should be created for children to represent themselves in the media.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2013
- Date added
- Aug 19, 2019
Paragraph
Harmful practices (joint General Recommendation with CRC) 2014, para. 67
- Paragraph text
- Childhood, and early adolescence at the latest, are entry points for assisting both girls and boys and supporting them to change gender-based attitudes and adopt more positive roles and forms of behaviour in the home, at school and in wider society. This means facilitating discussions with them on social norms, attitudes and expectations that are associated with traditional femininity and masculinity and sex- and gender-linked stereotypical roles and working in partnership with them to support personal and social change aimed at eliminating gender inequality and promoting the importance of valuing education, especially girls' education, in the effort to eliminate harmful practices that specifically affect pre-adolescent and adolescent girls.
- Body
- Committee on the Elimination of Discrimination against Women
- Document type
- General Comment / Recommendation
- Topic(s)
- Education
- Gender
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Boys
- Girls
- Year
- 2014
- Date added
- Aug 19, 2019
Paragraph
HIV/AIDS and the rights of the children 2003, para. 6
- Paragraph text
- Adequate measures to address HIV/AIDS can be undertaken only if the rights of children and adolescents are fully respected. The most relevant rights in this regard, in addition to those enumerated in paragraph 5 above, are the following: the right to access information and material aimed at the promotion of their social, spiritual and moral well being and physical and mental health (art. 17); the right to preventive health care, sex education and family planning education and services (art. 24 (f)); the right to an appropriate standard of living (art. 27); the right to privacy (art. 16); the right not to be separated from parents (art. 9); the right to be protected from violence (art. 19); the right to special protection and assistance by the State (art. 20); the rights of children with disabilities (art. 23); the right to health (art. 24); the right to social security, including social insurance (art. 26); the right to education and leisure (arts. 28 and 31); the right to be protected from economic and sexual exploitation and abuse, and from illicit use of narcotic drugs (arts. 32, 33, 34 and 36); the right to be protected from abduction, sale and trafficking as well as torture or other cruel, inhuman or degrading treatment or punishment (arts. 35 and 37); and the right to physical and psychological recovery and social reintegration (art. 39). Children are confronted with serious challenges to the above-mentioned rights as a result of the epidemic. The Convention, and in particular the four general principles with their comprehensive approach, provide a powerful framework for efforts to reduce the negative impact of the pandemic on the lives of children. The holistic rights-based approach required to implement the Convention is the optimal tool for addressing the broader range of issues that relate to prevention, treatment and care efforts.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Health
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Persons with disabilities
- Year
- 2003
- Date added
- Aug 19, 2019
Paragraph
HIV/AIDS and the rights of the children 2003, para. 11
- Paragraph text
- Children have the right not to have their lives arbitrarily taken, as well as to benefit from economic and social policies that will allow them to survive into adulthood and develop in the broadest sense of the word. State obligation to realize the right to life, survival and development also highlights the need to give careful attention to sexuality as well as to the behaviours and lifestyles of children, even if they do not conform with what society determines to be acceptable under prevailing cultural norms for a particular age group. In this regard, the female child is often subject to harmful traditional practices, such as early and/or forced marriage, which violate her rights and make her more vulnerable to HIV infection, including because such practices often interrupt access to education and information. Effective prevention programmes are only those that acknowledge the realities of the lives of adolescents, while addressing sexuality by ensuring equal access to appropriate information, life skills, and to preventive measures.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Health
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2003
- Date added
- Aug 19, 2019
Paragraph
Treatment of Unaccompanied and Separated Children Outside Their Country of Origin 2005, para. 42
- Paragraph text
- The unaccompanied or separated child should be registered with appropriate school authorities as soon as possible and get assistance in maximizing learning opportunities. All unaccompanied and separated children have the right to maintain their cultural identity and values, including the maintenance and development of their native language. All adolescents should be allowed to enrol in vocational/professional training or education, and early learning programmes should be made available to young children. States should ensure that unaccompanied or separated children are provided with school certificates or other documentation indicating their level of education, in particular in preparation of relocation, resettlement or return.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Education
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2005
- Date added
- Aug 19, 2019
Paragraph
The right of the child to rest, leisure, play, recreational activities, cultural life and the arts 2013, para. 14e
- Paragraph text
- [States parties recognize the right of the child to:] Appropriate to the age of the child: Article 31emphasizes the importance of activities appropriate to the age of the child. In respect of play and recreation, the age of the child must be taken into account in determining the amount of time afforded; the nature of spaces and environments available; forms of stimulation and diversity; the degree of necessary adult oversight and engagement to ensure safety and security. As children grow older, their needs and wants evolve from settings that afford play opportunities to places offering opportunities to socialize, be with peers or be alone. They will also explore progressively more opportunities involving risk-taking and challenge. These experiences are developmentally necessary for adolescents, and contribute to their discovery of identity and belonging.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Education
- Equality & Inclusion
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2013
- Date added
- Aug 19, 2019
Paragraph
The right of the child to rest, leisure, play, recreational activities, cultural life and the arts 2013, para. 37
- Paragraph text
- Resistance to children's use of public spaces: Children's use of public space for play, recreation and their own cultural activities is also impeded by the increasing commercialization of public areas, from which children are excluded. Furthermore, in many parts of the world, there is decreasing tolerance of children in public spaces. The introduction, for example, of curfews on children; gated communities or parks; reduced noise-level tolerance; playgrounds with strict rules for "acceptable" play behaviour; restrictions on access to shopping malls builds a perception of children as "problems" and/or delinquents. Adolescents, in particular, are widely perceived as a threat by widespread negative media coverage and representation, and discouraged from using public spaces.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2013
- Date added
- Aug 19, 2019
Paragraph
Harmful practices (joint General Recommendation with CEDAW) 2014, para. 67
- Paragraph text
- Childhood, and early adolescence at the latest, are entry points for assisting both girls and boys and supporting them to change gender-based attitudes and adopt more positive roles and forms of behaviour in the home, at school and in wider society. This means facilitating discussions with them on social norms, attitudes and expectations that are associated with traditional femininity and masculinity and sex- and gender-linked stereotypical roles and working in partnership with them to support personal and social change aimed at eliminating gender inequality and promoting the importance of valuing education, especially girls' education, in the effort to eliminate harmful practices that specifically affect pre-adolescent and adolescent girls.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Education
- Gender
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Boys
- Girls
- Year
- 2014
- Date added
- Aug 19, 2019
Paragraph
The implementation of the rights of the child during adolescence 2016, para. 1
- Paragraph text
- The Convention on the Rights of the Child defines a child as every human being below the age of 18 years unless under the law applicable to the child majority is attained earlier, and emphasizes that States should respect and ensure the rights embodied in the Convention to each child within their jurisdiction without discrimination of any kind. While the Convention recognizes the rights of all persons under 18 years, the implementation of rights should take account of children's development and their evolving capacities. Approaches adopted to ensure the realization of the rights of adolescents differ significantly from those adopted for younger children.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2016
- Date added
- Aug 19, 2019
Paragraph
The implementation of the rights of the child during adolescence 2016, para. 10
- Paragraph text
- As they move through their second decade, children begin to explore and forge their own individual and community identities on the basis of a complex interaction with their own family and cultural history, and experience the creation of an emergent sense of self, often expressed through language, arts and culture, both as individuals and through association with their peers. For many, that process takes place around and is significantly informed and influenced by their engagement with the digital environment. The process of construction and expression of identity is particularly complex for adolescents as they create a pathway between minority and mainstream cultures.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2016
- Date added
- Aug 19, 2019
Paragraph
The implementation of the rights of the child during adolescence 2016, para. 15
- Paragraph text
- The Committee emphasizes the importance of valuing adolescence and its associated characteristics as a positive developmental stage of childhood. It regrets the widespread negative characterization of adolescence leading to narrow problem-focused interventions and services, rather than a commitment to building optimum environments to guarantee the rights of adolescents and support the development of their physical, psychological, spiritual, social, emotional, cognitive, cultural and economic capacities.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2016
- Date added
- Aug 19, 2019
Paragraph
The implementation of the rights of the child during adolescence 2016, para. 16
- Paragraph text
- States, together with non-State actors, through dialogue and engagement with adolescents themselves, should promote environments that acknowledge the intrinsic value of adolescence and introduce measures to help them to thrive, explore their emerging identities, beliefs, sexualities and opportunities, balance risk and safety, build capacity for making free, informed and positive decisions and life choices, and successfully navigate the transition into adulthood. An approach is required that builds on strengths and recognizes the contribution that adolescents can bring to their lives and those of others, while addressing the barriers that inhibit those opportunities.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2016
- Date added
- Aug 19, 2019
Paragraph
The implementation of the rights of the child during adolescence 2016, para. 22
- Paragraph text
- The right of the child to have his or her best interests taken into account as a primary consideration is a substantive right, an interpretative legal principle and a rule of procedure, and it applies to children both as individuals and as a group. All measures of implementation of the Convention, including legislation, policies, economic and social planning, decision-making and budgetary decisions, should follow procedures that ensure that the best interests of the child, including adolescents, are taken as a primary consideration in all actions concerning them. In the light of its general comment No. 14 (2013) on the right of the child to have his or her best interests taken as a primary consideration, the Committee stresses that, when determining best interests, the child's views should be taken into account, consistent with their evolving capacities and taking into consideration the child's characteristics. States parties need to ensure that appropriate weight is afforded to the views of adolescents as they acquire understanding and maturity.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Governance & Rule of Law
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Children
- Year
- 2016
- Date added
- Aug 19, 2019
Paragraph
The implementation of the rights of the child during adolescence 2016, para. 28
- Paragraph text
- States need to invest in proactive measures to promote the empowerment of girls, challenge patriarchal and other harmful gender norms and stereotyping and legal reforms in order to address direct and indirect discrimination against girls, in cooperation with all stakeholders, including civil society, women and men, traditional and religious leaders and adolescents themselves. Explicit measures are needed in all laws, policies and programmes to guarantee the rights of girls on an equal basis with boys.
- Body
- Committee on the Rights of the Child
- Document type
- General Comment / Recommendation
- Topic(s)
- Equality & Inclusion
- Gender
- Social & Cultural Rights
- Person(s) affected
- Adolescents
- Boys
- Children
- Girls
- Men
- Women
- Year
- 2016
- Date added
- Aug 19, 2019
Paragraph