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Part 6 of 7 · Safety incident logger series ~5 min read

What the safety incident logger costs

A business reporting properly generates far more of these than one that is not, which is the point and also the only thing that scales the bill. Sixty reports a month across a few sites is a healthy reporting culture. Here is where each cent goes.

Key takeaways

  • About $1 a month at 60 reports. Roughly $2 at 250 reports.
  • One Bedrock read per report is the only line that scales. Everything else is rounding.
  • Nothing is always-on, so a quiet month genuinely costs almost nothing.
  • A rising bill here means a rising report count, which is the outcome the system is built to produce.
  • The duplicate test runs before the read, so resends are free.
  • The three real risks: a retry loop, storage nobody expires, and a bigger model than the job needs.

The bill at three volumes

These are US East prices at the time of writing, at three volumes that bracket most small businesses. Find the bar closest to your own and read across.

Monthly cost of the safety incident logger at three volumesA stacked bar chart with three bars, one per volume tier: 20 reports totalling about $1, 60 reports totalling about $1, and 250 reports totalling about $2. Each bar is stacked from bands. The largest and fastest-growing is Bedrock, one read per report, in teal. Then SES for the messages, in pink. Then S3 and DynamoDB storage in green. Then a fixed orange band for Secrets Manager and AWS Budgets, which is eighty-six cents at every volume. Then a grey band for Lambda, SQS and CloudWatch. A note says the read is the only bar that grows with the business and the orange band never moves.$0$1$2$3$4~$1.3220 reports~$1.4860 reports~$2.23250 reportsBedrock — one read per reportSES — asks, results, receiptsS3 + DynamoDBFixed — Secrets Manager, BudgetsLambda, SQS, CloudWatchThe read is the only bar that grows with the business. The orange fixed band never moves.
Fig 1. The monthly bill at three volumes. The teal band — one model read per report — is the only part that grows; the orange fixed band is the same 86 cents at every volume.

Line by line

LineAt 60 reportsHow it scales
Bedrock read$0.13Linear. One call per report, roughly 1,800 in and 200 out tokens.
SES$0.05Linear. About 2.6 messages per report.
DynamoDB + S3$0.29Storage grows with what you retain, not with throughput.
Lambda + SQS$0.12Linear, and effectively free at this scale.
CloudWatch$0.16Flat, if you set retention. Unbounded if you do not.
Secrets Manager$0.40Flat. One secret, $0.40 a month.
AWS Budgets$0.46Flat. Two actions, so you find out before the bill does.

The read is one model call per report to propose a severity and pick out the equipment and activity. Reports that trip the injury or vehicle keywords route before that call and are cheaper still.

The three ways this bill surprises you

Every one of these has happened to somebody, and all three are cheap to prevent.

  • Photos kept at full resolution forever. A yard photo is several megabytes and safety records are kept for years. Store a downscaled legible copy and expire the original at your actual retention horizon.
  • SMS on every high-severity route. Correct, and worth capping: a keyword false positive that texts three people costs little, and a loop that does it repeatedly does not. A maximum receive count of three on the queue.
  • Log retention left at never. Incident-adjacent logs are the ones you least want kept indefinitely, quite apart from the cost.

What it costs when nothing happens

This matters more than the headline number for a seasonal business. In a month with nothing to process the bill is the fixed band: Secrets Manager at forty cents, AWS Budgets at forty-six, and a few cents of storage. Call it a dollar. There is no instance to stop and nothing to remember to turn off.

The monthly bill at four volumes plus one failure modeA horizontal row of five boxes. Quiet month, about one dollar. 20 reports, about $1. 60 reports, about $1. 250 reports, about $2. And one bad retry loop, about two hundred dollars. A note says four of these are the design working and the fifth is a missing dead-letter queue.THE BILL, AT A GLANCEQuiet month~$120 reports~$160 reports~$1250 reports~$2One bad loop~$200Four of these are the design working. The fifth is a missing dead-letter queue.
Fig 2. The bill at a glance, including the one that is not a volume at all. A retry loop with no dead-letter queue costs more than every legitimate use of the system put together.
  • Management
  • Analytics
  • Front-end & mobile

Set these on day one

  • A dead-letter queue on every SQS queue, with a maximum receive count of three.
  • Thirty-day retention on every CloudWatch log group. There is no default that is safe.
  • An S3 lifecycle rule on the object prefix, tiering at 90 days and expiring at your actual record-keeping horizon.
  • Two AWS Budgets actions — one that emails at half your expected spend, one at double it. The second is how you find out about a loop in an hour instead of a month.
  • Provisioned concurrency: none. Nothing here is latency-sensitive enough to justify paying for a warm function.

Next: the same system drawn for engineers — service names, resource identifiers, IAM scopes, table schemas and the model id.

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