What this site knows about you.

This site is run by Winston Water Engineering, a sole practice in Singapore. Anything on this page — including a request to see or delete what is held about you — goes to contact@winstonwaterengineering.com, and reaches me rather than a queue. This notice is written with the Personal Data Protection Act 2012 in mind.

No account, no cookie, no record. The pages are static files and the calculators run entirely in your browser — the numbers you type into a design sheet are never sent anywhere, which is why they survive no further than the tab you typed them in. There is no analytics service here, so no profile of what you read exists for me to hold or for anyone else to buy.

Your browser does keep two things locally, and only your browser can read them: which colour theme you chose, and whether you dismissed the note on the homepage. Clearing site data removes both. Neither ever reaches the server.

As with any website, the web server keeps ordinary access logs — the address a request came from, the page asked for, and the time. These come with the hosting and are there for security and fault-finding, not analysis.

An account stores your email address and your password. The password is kept only as a one-way hash: I cannot read it, recover it, or tell you what it is, and a copy of the database would not contain it. Alongside those, the record holds the date it was created, when you last signed in, whether the address has been confirmed, the date any subscription runs to, and the references Stripe uses for your customer and subscription records.

Confirmation and password-reset links are single-purpose tokens. A reset link stops working one hour after it is sent.

Your card details never reach this site. Payment is taken entirely by Stripe, who are the processor; the page you type a card into is theirs, not mine. What comes back here is a reference, whether the subscription is active, and the date it runs to. I can see your receipts and cancel or refund a subscription. I cannot see your card number, and neither can this server.

The question box sends your name, email address, subject and message straight to my inbox as an email, with your address as the reply-to so I can answer. It is not put in a database. It stays in my mailbox like any other correspondence, and I delete it once it is no longer useful.

To stop the form being used to send bulk mail, the server keeps a short count of how many messages have come from one place recently. It holds a hash of the network address rather than the address itself, together with timestamps, and discards it after an hour.

Repeated failed sign-ins are rate-limited. That check records the network address, the email address tried, and the time — and deletes every row older than one hour. It exists to slow down someone guessing passwords and is used for nothing else.

• A session cookie. Set when you sign in, so the site knows the next page request is still you. It is marked HttpOnly, Secure and SameSite=Lax, so no script can read it and it is not sent from other sites. It ends when you sign out.
• Two label cookies. One records that somebody is signed in on this browser and one that the design sheets are open, so a plain HTML page can say “Account” rather than “Sign in” and stop advertising a subscription you already have. Neither holds any identity, and neither is ever consulted when deciding what anyone may see — that decision is made on the server every time.

There are no advertising, tracking or analytics cookies, which is why this site has no cookie banner to dismiss.

• Stripe — payment. They hold your card and billing details; this site never does.
• Resend — delivers confirmation, password-reset and receipt emails, and handles your address in order to do so.
• The web host — the server and database sit on hosting infrastructure in Singapore, so the provider has access to the machine.
• Payhip — only if you buy the Excel workbook. That sale happens on their site under their own terms.
• Google Fonts — the typefaces this site is set in are served by Google, so your browser fetches them on each visit. That request tells Google your network address and which browser you use. No cookie is set on those requests and nothing else is sent.

Nothing is sold, rented, shared for advertising, or passed to anyone not named here. There is no mailing list: the only email this site sends is about something you did — confirming an address, resetting a password, or a subscription starting.

• Your account — until you ask for it to be deleted.
• Rate-limit records — deleted automatically after one hour.
• Password-reset links — one hour, then they stop working.
• Payment records — held by Stripe for as long as the law requires transaction records to be kept.
• Messages you send me — kept in my mailbox while they are useful, then deleted.

You can ask to see everything held about you, to have it corrected, or to have the account and its data deleted. Email contact@winstonwaterengineering.com from the address on the account and I will do it. Deleting an account does not by itself cancel anything at Stripe, so say if you want a live subscription cancelled too and I will do both.

If this notice changes in a way that affects what is collected or who sees it, the date below changes with it, and the change is listed on the version history page like everything else on this site.

Last updated 7 October 2026